Espaņol
|
||||||||||||||||||||||||||||||||||||||||
|
CAAA: Clean Air Act Amendments of 1990. Cabinet Certification: Measurement and/or correction of safety cabinet air velocities, patterns, balance, leakage and filtration system efficiency by a qualified technician after which the unit meets standard specifications. Cabinet Classification: Class I: A ventilated cabinet for personnel and environmental protection which may be operated with an open front, or with a gloveport panel in place, with or without gloves attached. The cabinet exhaust air may be filtered through a HEPA and/or charcoal filter before being discharged to the outside atmosphere. This cabinet is suitable for work with low and moderate risk biological agents where no product protection is required. Class II: (Formerly called laminar flow biological safety cabinet), a ventilated cabinet for personnel, product and environmental protection having an open front with inward airflow for personnel protection and a mass recirculated HEPA-filtered airflow for product protection. The cabinet exhaust air is filtered through a HEPA filter for environmental protection. This cabinet is suitable for work with low to moderate risk biological agents. Vapors or gases which are hazardous from a toxic, radioactive, or flammability standpoint should not be used in cabinets which recirculate all or part of the air. Consideration of use of such materials should be evaluated carefully from the standpoint of build-up to dangerous levels and problems of decontamination of the cabinet. Class III: A closed front ventilated cabinet with negative pressure of gas-tight construction providing total protection for personnel and product from contaminants exterior to the cabinet. Supply and exhaust air is suitably treated to protect the environment. This cabinet, fitted with rubber gloves, provides the highest containment reliability of these three classes and is utilized for all activities involving high risk agents. Cable Winder: See “Cord Winder.” CADR: Clean Air Delivery Rate (CADR) provides the number of cubic feet of clean air a unit delivers each minute. Efficiency of the system times the air flow of the system. Clean Air Delivery Rate is a measure of the air purifier’s ability to reduce smoke, dust, and pollen particles in the 0.1 to 11 micron size range from the air. CADR is defined as “the rate of contaminant reduction in the test chamber (1008 sq. ft) when the unit is turned on, minus the rate of natural decay when the unit is not running, multiplied by volume of the test chamber as measured in cubic feet. CAE: The Combined Annual Efficiency is a measure of the amount of heat produced for every dollar of fuel consumed for both home and water heating. Caisson: A 10" or 12" diameter hole drilled into the earth and embedded into bedrock 3 - 4 feet. The structural support for a type of foundation wall, porch, patio, monopost, or other structure. Two or more “sticks” of reinforcing bars (rebar) are inserted into and run the full length of the hole and concrete is poured into the caisson hole. Cake (Filter): Solids deposited on the filter media. In many cases the cake may serve as its own filter medium. Cake Release: Ability of a medium to allow clean separation of the cake from the medium. Caking: Material crusted on a bag that cannot be removed by the cleaning mechanism. Frequently caused by the dust on the bags getting wet. Calcium Sulfate: Used as a drying agent or desiccant in the liquid line driers. Calendaring: The application of either hot or cold pressure to smooth or polish a fabric, thereby reducing the thickness of the cloth by spreading the warp and filling yarns into a ribbon shape. Calendering: A manufacturing process where woven and/or nonwoven fabrics are pressed between heavy rollers compressing the fibers. The process reduces the filter medium void volume, pore size rating, flow-rate and dirt-hold capacity of the medium. Calibrate: To check, adjust, or determine by comparison with a standard (the graduations of a quantitative measuring instrument): calibrate a thermometer. Calibration: The act or process of calibrating or the state of being calibrated. California Air Pollution Control Officers Association (CAPCOA): A nonprofit association of the air pollution control officers from all 35 air quality agencies throughout California. CAPCOA was formed in 1975 to promote clean air and to provide a forum for sharing of knowledge, experience, and information among the air quality regulatory agencies around the state. CAPCOA is an organization of air quality professionals – leaders in their field – who promote unity and efficiency, and strive to encourage consistency in methods and practices of air pollution control. California Air Resources Board (ARB): The State’s lead air quality agency consisting of an eleven-member board appointed by the Governor and several hundred employees. CARB is responsible for attainment and maintenance of the state and federal air quality standards, and is fully responsible for motor vehicle pollution control. It oversees county and regional air pollution management programs. California Ambient Air Quality Standard (CAAQS): A legal limit that specifies the maximum level and time of exposure in the outdoor air for a given air pollutant and which is protective of human health and public welfare (Health and Safety Code section 39606b). CAAQSs are recommended by the California Office of Environmental Health Hazard Assessment and adopted into regulation by the CARB. CAAQSs are the standards which must be met per the requirements of the California Clean Air Act (CCAA). California Clean Air Act (CCAA): A California law passed in 1988 which provides the basis for air quality planning and regulation independent of federal regulations. A major element of the Act is the requirement that local air districts in violation of the CAAQS must prepare attainment plans which identify air quality problems, causes, trends, and actions to be taken to attain and maintain California’s air quality standards by the earliest practicable date. California Code of Regulations (CCR): The California Code of Regulations (CCR) contains the text of the regulations formally adopted by state agencies, reviewed and approved by the Office of Administrative Law, and filed with the Secretary of State. The CCR consists of 28 titles and contains the regulations of approximately 200 regulatory agencies. California Environmental Protection Agency (Cal/EPA): A state government agency established in 1991 for unifying environmental activities related to public health protection in the State of California. There are six boards, departments, and offices under the organization of Cal/EPA including the California Air Resources Board (ARB), California Integrated Waste Management Board (IWMB), State Water Resources Control Board (SWRCB) and its nine Regional Water Quality Control Boards (RWQCB), Department of Pesticide Regulation (DPR), Department of Toxic Substances Control (DTSC), and Office of Environmental Health Hazard Assessment (OEHHA). The Cal/EPA boards, departments, and offices are directly responsible for implementing California environmental laws, or play a cooperative role with other regulatory agencies at regional, local, state, and federal levels California Environmental Quality Act (CEQA): A California law that sets forth a process for public agencies to make informed decisions on discretionary project approvals. The process aids decision makers to determine whether any environmental impacts are associated with a proposed project. It requires environmental impacts associated with a proposed project to be eliminated or reduced, and that air quality mitigation measures are implemented. Established law of environmental protection, maintenance and enhancement. California Environmental Quality Act of 1970 (CEQA): Statute that requires that all California state, local, and regional agencies document, consider, and disclose to the public the environmental implications of their actions. California Water Code (CWC): The Porter Cologne Water Quality Control Act. Calorie: The amount of heat (by weight) that is required to raise the temperature of water 1 degree Celsius. Calorific Value: The energy content per unit mass, per unit volume or released if reacting with usually oxygen (burned). Calorimeter: Device used to measure the quantities of heat. Cam: Mechanical component that is oblong, giving a reciprocating motion when rotated. Camber: A slightly arched surface, as of a road, a ship’s deck, an airfoil, or a snow ski. Camber Arch: An arch whose intrados, though apparently straight, has a slightly concave curve upward. Camber Beam: A beam whose under side has a concave curve upward. Camber Windows: Casement windows with a curved top. Can Velocity: The velocity of the gas in the passages between the filter units in the filter house of a gas filter. Cancer: A group of diseases characterized by uncontrolled invasive growth of body cells leading to the formation of malignant tumors that tend to grow rapidly and spread (i.e., metastasize). Candela (cd): SI (Standard International) unit of luminous intensity: the candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 1012 hertz and has a radiant intensity in that direction of 1/683 watt per steradian. (16th General Conference of Weights and Measures, 1979). Candela per Square Metre: (cd/m2): SI unit of luminance. (Note: this unit was sometimes called the nit [nt] (name discouraged). Other units of luminance: 10-4 metric, non-SI: Lambert (L). Candle Filter: A reusable filter consisting of a tube made from ceramics or metal. Flow is from the outside-in with particulate accumulating on the outside of the candle. The candle can be cleaned by various means, including back-pulsing, heat, chemicals etc. Canister: A container similar to a cartridge, but larger in size; see cartridge. Canister or Cartridge: A container with a filter, sorbent, or catalyst, or combination of these items, which removes specific contaminants from the air passed through the container. Canister Type Vacuum Cleaner: The simplest way to understand the difference between a canister and an upright vacuum cleaner is that you pull a canister and push an upright. A canister vacuum cleaner has a base unit that contains the vacuum motor, dust bag and filter system. There are three types of canister vacuum cleaners. All three are used with a hose and attachments. The difference is in the attachments. A canister that has no power nozzle of any kind is called a Straight Suction Canister. It is suitable for environments with no or very little carpet. The second type is a canister with a turbo or turbine power nozzle, which is a power nozzle with a revolving brush that is powered by the airflow created by the canister's suction motor. This type of canister is a good choice when soiling conditions are moderate or the amount of carpet and rugs in the home is minimal. The third type of canister features a power nozzle where a separate electric motor drives the brush roll. This type of canister is often referred to as a Power Team and is ideal for homes with large amounts of carpet or rugs and standard to heavy soiling conditions. Cannula: A small plastic tube used to supply extra oxygen through the nose. Canopy: An overhanging roof. Cant Strip: A beveled support used at the junction of a flat surface and a vertical surface to prevent bends and/or cracking of the roofing membrane at the intersection of the roof deck and wall. Used with a base flashing to minimize breaking of the roofing felts. Cantilever: A projecting beam or other structure supported only at one end. Any part of a structure that projects beyond its main support and is balanced on it. Cantilevered Void: Foundation void material used in unusually expansive soil conditions. This void is "trapezoid" shaped and has vertical sides of 6” and 4” respectively. Cap: The pressure screw cover and/or lever housing on a valve. May be screwed, bolted. packed, or plain lever. A layer, such as clay or a synthetic material, used to prevent rainwater from percolating through soil and waste and spreading contamination. The upper member of a column, pilaster, door cornice, molding, and the like. CAP88-PC: Computer code required by the EPA for modeling air emissions of radionuclides. Cap Flashing: The portion of the flashing attached to a vertical surface to prevent water from migrating behind the base flashing. Cap Sheet: A top layer in built-up roofing. Cap Sheets: In roofing, one to four plies of felt bonded and top-coated with bitumen that is laid over an existing roof as a treatment for defective roofs. Cap Tube: A restrictive tube used in a refrigeration system which restricts the flow of freon and allows pressure to build on one side and suction on the other. It is located between the condenser and the evaporator. Capacitance: Ability of a circuit system to store electricity. The capacitance of a capacitor is measured in farads and is determined by the formula C = q/V, where q is the charge (in coulombs) on one of the conductors and V is the potential difference (in volts) between the conductors. The capacitance depends only on the thickness, area, and composition of the capacitor’s dielectric. Capacity: The output or producing ability of cooling or heating systems. Cooling and heating capacities are referred to in British thermal units (BTUs) per hour. Capacity of a compressor is the full rated volume of flow of gas compressed and delivered at certain set conditions. Volume of product which a housing will accommodate expressed in gallons or similar units. Also, amount which will filter at a given efficiency and flow rate, expressed in gallons per minute or similar units.
Capacity Filtration: The amount of air that a filter can handle. Expressed in CFM. Capacity Gauge: A gauge that measures air flow as a percentage of capacity, used in rotary screw compressors as an estimator during modulation controls. Cape Chisel: Tool used to clean out mortar joints on brick. Capillary Forces: Forces that cause ground water to rise above the surface of the saturated zone into the spaces between soil particles in the unsaturated zone. Capillary Tube: A restrictive tube used in a refrigeration system which restricts the flow of freon and allows pressure to build on one side and suction on the other. It is located between the condenser and the evaporator. Capital: The principal part of a loan, i.e. the original amount borrowed. Capital and Interest: A repayment loan and the most conventional form of home loan. The borrower pays an amount each month to cover the amount borrowed (capital or principal) plus the interest charged on capital. Capped Rate: The mortgage interest rate will not exceed a specified value during a certain period of time, but it will fluctuate up and down below that level. Capsules: Disposable devices which have an integrated filter and housing, including inlet and outlet. Capture Efficiency: The fraction of organic vapors generated by a process that are directed to an abatement or recovery device. Capture Velocity: The air velocity at any point in front of a hood or at a hood opening necessary to overcome opposing air currents and to capture the contaminated air at that point by causing it to flow into the hood. Carbon Adsorption: A treatment system in which organic contaminants are removed from air, ground water, and surface water by contact with activated carbon, a specially-treated material that retains such compounds. Carbon Canister Vapor Capture: An automotive filter in which activated carbon has been placed so that gas tank fuel vapors, which have accumulated when the vehicle is not running, are trapped in the filter. When the engine is running, hot air is forced into the filter and pushes out the vapors into the engine. In this way pollution is reduced and fuel conservation is maintained. Carbon Dioxide (CO2): A colorless, odorless, nonpoisonous gas which results from fuel combustion and human activity indoors. Elevated levels of CO2 indicate ineffective ventilation indoors. A heavy colorless gas that does not support combustion but is formed by the combustion and decomposition of organic substances. Found in some ambient air conditions. Carbon Filter: Air filter housing activated carbon. Carbon Monoxide (CO): A colorless, odorless, poisonous gas which results from incomplete combustion. Carbon Tetrachloride: A chemical used as a solvent for removing grease oil and sludge. Carbonate: A salt or ester of carbonic acid. Carboxyhemoglobin (COHb): A stable complex of carbon monoxide and hemoglobin that forms in red blood cells when carbon monoxide is inhaled, and inhibits delivery of oxygen to the body. Carcinogen: A substance that can cause or contribute to cancer. A cancer-causing substance. (See also cancer.) A substance is considered to be a carcinogen if: (a) It has been evaluated by the International Agency for Research on Cancer (IARC). Monographs and found to be a carcinogen or potential carcinogen; or (b) It is listed as a carcinogen or potential carcinogen in the Sixth Annual Report on Carcinogens published by the National Toxicology Program (NTP) or, (c) It is regulated by Fed/0OSHA or Cal/OSHA as a carcinogen. Carcinogenic: Cancer-producing or cancer-causing. Cardiac Arrhythmia: Irregular beating of the heart. Cardiovascular: Pertaining to the heart and blood vessels. Cardiovascular Diseases: A group of diseases of the blood vessels that includes coronary heart disease, stroke, and hypertension. Carl Moyer Fund: A multi-million dollar incentive grant program designed to encourage reduction of emissions from heavy-duty engines. The grants cover the additional cost of cleaner technologies for on-road, off-road, marine, locomotive and agricultural pump engines, as well as forklifts and airport ground support equipment. Carpal Tunnel Syndrome: A common affliction caused by compression of the median nerve in the carpal tunnel. Often associated with tingling, pain or numbness in the thumb and first three fingers. Carriers: Seemingly healthy people who harbor disease-causing microbes in the body and who can infect others by passing the microbes on to them. Carrying Velocity: The gas velocity that is necessary to keep contaminants airborne. Usually between 2,000 to 5,000 ft/min in duct work, depending on the nature of the contaminant. CAS: Chemical Abstracts Service is an organization under the American Chemical Society. CAS abstracts and indexes chemical literature from all over the world in “Chemical Abstracts.” “CAS Numbers” are used to identify specific chemicals or mixtures. CAS Registry Number: The Chemical Abstracts Service Registry Number (CAS) is a numeric designation assigned by the American Chemical Society’s Chemical Abstract Service and uniquely identifies a specific compound. This entry allows one to conclusively identify a material regardless of the name or naming system used. Cascade System: Arrangement in which two or more refrigerating systems are used in series. Casing: The pressure containing stationary element that encloses the rotor and associated internal components of a compressor, including integral inlet and discharge connections. Exposed molding or trim around a window or door. Casement Frames and Sash: Frames of wood or metal enclosing part or all of the sash, which may be opened by means of hinges affixed to the vertical edges. Cast Iron: Heavy metal formed by casting on molds. The metal is covered with a porcelain enamel coating to make fixtures such as the cast iron tubs. Cast-Iron Pipe (Plumbing): Drain and vent lines. Most older drain-waste venting systems are made of cast-iron pipes. Now increasingly supplanted by ABS and PVC. Pipes were originally joined with molten lead, but most plumbers now join them with no-hub couplers. Casual Gain: See internal gains. Catalyst: A substance that can increase or decrease the rate of a chemical reaction between the other chemical species without being consumed in the process. Catalytic Converter: A motor vehicle pollution control device designed to reduce emissions such as oxides of nitrogen, hydrocarbons, and carbon monoxide. Catalytic converters have been required equipment on all new motor vehicles sold in California since 1979. Catalytic Incinerator: A control device that oxidizes volatile organic compounds (VOCs) by using a catalyst to promote the combustion process. Catalytic incinerators require lower temperatures than conventional thermal incinerators, thus saving fuel and other costs. Catch Basin: A drain for a low or wet spot, with pipe exiting the side and a pit at the bottom to collect sediment. Catechin: Catechin is a bitter tasting component found in many plants, and is a type of polyphenol found in abundance in tea, it possesses antibacterial and antiviral properties. It is used in clothing such as underwear and in products such as masks and bedding. Catecholamines: A group of compounds with active roles in the sympathetic and parasympathetic nervous systems. This group includes adrenalin (epinephrin is another name for the same compound) which is a hormone secreted by the adrenal gland, and noradrenalin (norepinephrin is another name for the same compound). Effects include blood vessel constriction and increase in blood pressure, and increased heart rate. Categorical Discharge: Discharge from a process regulated by EPA rules for specific industrial categories. Cathode: Negative pole or electrode of an electrolytic system. Caulking: Mastic compound for filling joints and cracks. Caustic: Able to burn, corrode, dissolve, or eat away other substances. A class or name given to a class or group of chemicals, usually soda or sodium hydroxide. Caustic Soda: Sodium hydroxide, a strong alkaline substance used as the cleaning agent in some detergents. CBA: See compressed breathing air. CBR: Chemical Biological Radiological. CCA (Chromated Copper Arsenate): A pesticide that is forced into wood under high pressure to protect it from termites, other wood boring insects, and decay caused by fungus. CCG: Canadian Coast Guard. CCME: Canadian Council of Ministers of the Environment. CCOHS: Canadian Centre for Occupational Health and Safety. CD: Refers to the “cross-machine” manufacturing direction of filtration roll stock. CDRP: Certified Disaster Recovery Planner. Ceiling Joist: One of a series of parallel framing members used to support ceiling loads and supported in turn by larger beams, girders or bearing walls. Also called roof joists. Ceiling Limit: In threshold limit value (TLV) and permissible exposure limit (PEL), the maximum allowable concentration to which an employee may be exposed. Ceiling Plenum: Space below the flooring and above the suspended ceiling that accommodates the mechanical and electrical equipment and that is used as part of the air distribution system. The space is kept under negative pressure. Cell: The smallest and most fundamental unit of life. Cells (Masonry): The hollow spaces in concrete blocks. Cellulose: (1) Fibers used to manufacturer wetlaid paper; (2) used as a filter aid in highly refined alpha cellulose form or as the slightly more unbleached form. Cellulose Insulation: Insulation, packaged in bags for blowing, made from newspaper or wood waste and treated with a fire retardant. Celotex: Black fibrous board that is used as exterior sheething. Celsius: The metric temperature scale in which water freezes at zero degrees and boils at 100 degrees, designated by the symbol “C.” To convert to Fahrenheit, multiply a Celsius temperature by 9, divide by 5 and add 32 (25 x 9 equals 225, divided by 5 equals 45, plus 32 equals 77 degrees Fahrenheit). °C The international temperature scale where water freezes at 0 (degrees) and boils at 100 (degrees). Also known as the centigrade scale. Celsius Temperature Scale: Temperature scale used in metric system. Cement: The gray powder that is the “glue” in concrete. Portland cement. Also, any adhesive. Cement Mixtures: Rich - 1 part cement, 2 parts sand, 3 parts coarse aggregate. Used for concrete roads and waterproof structures. Standard - 1 part cement, 2 parts sand, 4 parts coarse aggregate. Used for reinforced work floors, roofs, columns, arches, tanks, sewers, conduits, etc. Medium - 1 part cement, 2 1/2 parts sand, 5 parts coarse aggregate. Used for foundations, walls, abutments, piers, etc. Lean - 1 part cement, 3 parts sand, 6 parts coarse aggregate. Used for all mass concrete work, large foundations, backing for stone masonry, etc. Mixtures are always listed Cement to Sand to Aggregate. CEN: The European Standards Institution. Center Tube: The internal duct and filter medium support Center Core or Tube: Material formed into a cylinder shape for structural purposes to permit a cartridge to retain its original physical form. Center Pipe or Rod: Component of a housing which is used as a mount for cartridges, typically through the center core. Centerset: A style of faucet that is installed on a lavatory with 4” center-to-center faucet holes and that has the spout and handle(s) combined into a single part. Centigrade: A temperature scale on which water freezes at 0 degrees and boils at 100 degrees. Centimeter: Metric unit of linear measurement. Centipoise (cP): (N s/m2; N = Newton) A unit of absolute viscosity. One centipoises equals 0.01 stoke. Central Air Conditioning: See Air Conditioner. Central Air Handling Unit (Central AHU): For purposes of this document, this is the same as an AHU, but serves more than one area. Central Station: Central location of condensing unit with either wet or air-cooled condenser. Evaporator located as needed and connected to the central condensing unit. Central Valley Regional Water Quality Control Board (CVRWQCB): Local agency responsible for regulating ground and surface water quality in the Central Valley. Centralized Computerized Controller: Energy control device, centrally located, which makes control decisions based on operating data, programmed information, and stored data. Centrifugal Compressor: A dynamic compressor. A machine in which air or gas is compressed by the mechanical action of rotating vanes or impellers imparting velocity and pressure to the air or gas. In a centrifugal compressor, flow is in a radial direction. Air enters the compressor through the machine mounted inlet control valve and flows to the first stage where the impeller imparts velocity energy to the air. The air then proceeds through a diffuser section which converts the velocity energy to pressure energy. A multistage centrifugal compressor is a machine having two or more of these stages. Centrifugal Fan: A device that draws air in axially and discharges it radially. Centrifugation: Separating two substances of differing densities by high speed spinning to create centrifugal force. Generally used to separate suspended particles from liquid. CEPA 1999: Canadian Environmental Protection Act, 1999. An Act that respects the prevention of pollution and the protection of the environment and human health in an effort to contribute to sustainable development. Ceramic Disk Valve: A type of valve that relies on two-part revolving disks in a sealed cylinder. Each disk has a port in it that, when aligned with the other, will allow water to pass through. Ceramic Tile: A man-made or machine-made clay tile used to finish a floor or wall. Generally used in bathtub and shower enclosures and on counter tops. CERCLA: Comprehensive Environmental Response, Compensation and Liability Act of 1980. Commonly known as “Superfund.” (U.S.EPA) Certificate of Occupancy: A document stating that a building is approved for occupancy. The Building Authority issues the Certificate of Occupancy. Certification: In the context of laminar flow and safety cabinets installations, documentation of test results showing the results of performance testing to Australian or other standards. On-site testing, mandatory for safety cabinets prior to use, is typically repeated annually and more frequent testing may be specified in highly critical applications. Certified: Having a formal document testifying to qualification or completion of requirements. Cervical Dislocation: A physical euthanasia technique where pressure is applied to the neck to dislocate the spinal column from the skull, normally only conducted on small animals. CF: Canadian Forces. CFCs (chlorofluorocarbons): Chemicals used in industry for refrigeration and air conditioning, and in consumer products. CFCs and their relatives, when released into the air, rise into the stratosphere, a layer of the atmosphere high above the Earth. In the stratosphere, CFCs and their relatives take part in chemical reactions which result in reduction of the stratospheric ozone layer, which protects the Earth's surface from harmful effects of radiation from the sun. The 1990 Clean Air Act includes provisions for reducing releases (emissions) and eliminating production and use of these ozone-destroying chemicals. CF H Svcs Gp HQ: Canadian Forces Health Services Group Headquarters. CFAO: Canadian Forces Administrative Orde. CFB: Canadian Forces Base. CFFM: Canadian Forces Fire Marshal. Cfm: See cubic feet per minute. CFMG: Canadian Forces Medical Group. CFR: Code of Federal Regulations. CFTO: Canadian Forces Technical Order. CFTO C-87-040-000/MS-001: The DND Respiratory Protection Program Technical Order. CFM: ACRONYM – Cubic feet per minute. An airflow measurement of volume. CFMn: The cubic feet of air flowing through a house from indoors to outdoors during typical, natural conditions. This figure can be roughly estimated using a blower door. CFM Per Person or Per Room: An estimate of the cubic feet per minute of fresh air available or required per occupant or per room. CFR: The Code of Federal Regulations refers to the Federal laws of the United States. CFUs: Colony Forming Units; individual regions of growth attributed to a single reproductive unit such as a spore or vegetative cell. CGA: Compressed Gas Association (USA). Chain-of-Custody: Method for documenting the history and possession of a sample from the time of its collection, through its analysis and data reporting, to its final disposition. Chair Rail: A molding that runs horizontally along the wall at about 3 feet from the ground. In storefront, window wall, or curtain wall systems, a chair rail is an aluminum extrusion applied horizontally to the inside of the system 3 feet from the floor to create a barrier in floor-to-ceiling glazing applications. Chalk Line: A line made on the roof by snapping a taut string or cord dusted with chalk. Used for alignment purposes. Challenge Agent: An easily identified agent in the air; it may be irritating, or have a strong smell or taste. Challenge Concentration: The concentration of an aerosol of known character used to test a filter, under specified conditions, for the purpose of determining efficiency and/or leakage. Change of State: The point at witch a substance changes from a solid to a liquid or a liquid to a gas due to addition of heat. Or, the reverse, in which a substance changes from a gas to a liquid, or a liquid to a solid, due to removal of heat. Change Order: A written document which modifies the plans and specifications and/or the price of the Construction Contract. Channel Glazing: The installation of glass products into U-shaped glazing channels. The channels may have fixed stops; however, at least one glazing stop on one edge must be removable. Chapter: A local group of members of a larger association, as in a local NACHI Chapter. A local branch. Charcoal Filter: These filters use activated charcoal to absorb odors from the air. Odorous molecules are absorbed but are not broken down by charcoal filters, meaning that odors are re-released back into the air once the filter is saturated. Activated charcoalfilters are also disposable and therefore contribute to environmental pollution. Charging: To add a charge of refrigerant to a system. Charle’s Law: States that the volume of a gas, at constant pressure, varies directly with the absolute temperature. Chase: A framed enclosed space around a flue pipe or a channel in a wall or through a ceiling for something to lie in or pass through. Chatter: Abnormal, rapid reciprocating movement of the disc on the seat of a pressure relief valve. Check Valve: A valve that permits flow in one direction only. Checking: Fissures that appear with age in many exterior paint coatings. At first superficial, but in time may penetrate entirely through the coating. It produces a pattern of surface cracks running in irregular lines. When found in the top pour of an asphalt built-up roof, checking is the preliminary stage of alligatoring. Checkrails: Meeting rails sufficiently thicker than a window to fill the opening between the top and bottom sash made by the parting stop in the frame of double-hung windows. They are usually beveled. Chemical Cartridge Respirator: A respirator that uses various chemical substances to purify inhaled air of certain gases and vapors. This type respirator is effective for concentrations no more than ten times the TLV of the contaminant, if the contaminant has warning properties (odor or irritation) below the TLV. Chemical Mediators: A group of chemical compounds (proteins, mostly) that help to cause inflammation. Chemical Mixture: Any combination of two or more substances. Chemical Sensitization: Evidence suggests that some people may develop health problems characterized by effects such as dizziness, eye and throat irritation, chest tightness, and nasal congestion that appear whenever they are exposed to certain chemicals. People may react to even trace amounts of chemicals to which they have become "sensitized." Chemisorb: To take up and hold, usually irreversibly, by chemical forces. CHEMTREC: Chemical Transportation Emergency Center. Public service of the Chemical Manufacturers Association that provides immediate advice for those at the scene of hazardous materials emergencies. CHEMTREC has a 24-hour toll-free telephone number (800-424-9300) to help respond to chemical transportation emergencies. Chiller: A device which circulates air past chilled pipes to provide cooling. The pipes are typically chilled by circulating cold water or other heat transfer fluid. Chimney: A masonry or metal stack that creates a draft to bring air to a fire and to carry the gaseous byproducts of combustion safely away. Chemistry and Materials Science Environmental Services: LLNL laboratory that analyzes environmental samples. Chilled Water System: A type of air conditioning system that has no refrigerant in the unit itself. The refrigerant is contained in a chiller, which is located remotely. The chiller cools water, which is piped to the air conditioner to cool the space. Chimney: Vertical shaft for carrying flue gases to the outside atmosphere. Chimney Connector: A pipe connecting the heating appliance with the chimney. Chimney Effect: See stack effect. The tendency of heated air or gas to rise in a duct or other vertical passage, such as in a chimney, small enclosure, or building, due to its lower density compared to the surrounding air or gas. Chimney Flue: The passageway in a chimney. Chip Board: A manufactured wood panel made out of 1”- 2” wood chips and glue. Often used as a substitute for plywood in the exterior wall and roof sheathing. Also called OSB (Oriented Strand Board) or Wafer Board. Chip Control: A filter intended to prevent only large particles from entering a component immediately downstream. Chipping Hammer: A hand held pneumatic tool. Designed to chip masonry, plaster, concrete etc. Chloramphenicol: Chloramphenicol is an antibiotic once in common use in veterinary medicine but now banned in food producing animals, due to the potential for bone marrow depression of blood cell production. Chloride: A compound in which chlorine is combined with any of certain other elements or with a radical. Chlorinated Solvents: Organic solvents containing chlorine atoms. Examples include methylene chloride, perchloroethylene and 1, 1, 1 trichloroethylene used as cleaning agents. Chlorine: A chemical element that is a heavy strong smelling greenish yellow imitating gas used as a bleach, oxidizing agent and disinfectant. Found in some ambient air conditions. Chlorofluorocarbons (CFCs): Compounds containing chlorine, fluorine or bromine, used as aerosol propellants, refrigerants, foaming agents and solvents and which, on decomposition by sunlight, produce oxides of chlorine responsible for the removal of ozone from the stratosphere. Choke: This term is used for turbo compressors and represents the maximum flow condition. It is sometimes also referred to as stonewalling. Choke Tube: Throttling device used to maintain correct pressure difference between high side and low side in refrigerating mechanism. Chromatography: Separation of substances in a mixture based on their affinity for certain solvents and solid surfaces. Chronic: Conditions that occur over a long period of time, either continuously or intermittently; describes effects that develop only after a long exposure. Chronic Bronchitis: Inflammation of the smaller airways in the lung usually caused by bacterial or viral infection. Chronic Effect: An adverse effect on a human or animal body, with symptoms which develop slowly over a long period of time or which recur frequently. Also see “acute.” Chronic Health Effect: A health effect that occurs over a relatively long period of time (e.g., months or years). (See also acute health effect.) Chronic Obstructive Pulmonary Disease (COPD): A disease with shortness of breath, cough and sputum production most commonly caused by chronic bronchitis and emphysema. Bronchitis is inflammation of the smaller airways in the lung usually caused by bacterial or viral infection. Emphysema is characterized by disabling breathlessness caused by loss of the thin walls dividing the air spaces (alveoli), which reduces the area available for the exchange of oxygen and carbon dioxide. Chronic Toxicity: The ability of a substance to cause long-term poisonous human health effects. Toxicity involving a stimulus that lingers or continues for a relatively long period of time, often one-tenth the life span or more. “Chronic” should be considered a relative term depending on the life span of an organism. A chronic toxic effect can be measured in terms of reduced growth, reduced reproduction, etc., in addition to lethality. Chronic Wasting Disease (CWD): Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy of elk and other deer, first recognized the 1960s in Colorado and identified as a prion disease in the late 1970s. Deer with CWD have been found in game farms, and wild elk and deer with CWD have been found in the USA and Canada. CIBSE: The Chartered Institution of Building Services Engineers. CID Aerosol: Acidic liquid or solid particles that are small enough to become airborne. High concentrations of acid aerosols can be irritating to the lungs and have been associated with some respiratory diseases, such as asthma. CIE Standard Overcast Sky: completely overcast sky for which the ratio of its luminance Ly in the direction at an angle X above the horizon to its luminance Lz at the zenith is given by the relation Ly=Lz(1+2sinX)/3. CIE Standard Sources: Artificial sources specified by the CIE, whose radiations approximate CIE standard illuminants A, B and C, (see CIE Publication N015). CIH: Certified Industrial Hygienist. Cilia: Hair-like structures that line the airways in the lungs and help to clean out the airways. Cinogenic: Able to induce a cancer response at the cellular level. Circuit Breaker: A device found in a Circuit Panel Box that completes an electric circuit. This breaker disconnects the circuit from electricity when it senses an overload of current.
Cistern: Reservoir for water. Common in houses built prior to the fifties in the Midwest. Clarification: Clearing a liquid by filtration, by the addition of agents to precipitate solids, or by other means. Clarifier: An apparatus for the removal of settleable solids from a fluid by gravity. A processing unit using flocculation processes to separate solids from liquid often in a non-turbulent zone where heavy solids settle out of solution. Often used for wastewater. Clarity: Amount of contaminate left in a filtered liquid. Class A Fire: Wood, paper cloth, trash or other ordinary materials. Class B Door: A fire resistant rating applied by the Underwriters Laboratories Classification for a door having a 1 to 1 1/2 hour rating. Class B Fire: Gasoline, grease, oil, paint or other flammable liquids. Class C Fire: Live electrical equipment. Class D Fire: Flammable metals. Class “A” Fire Resistance: The highest fire-resistance rating for roofing per ASTM E-108. Indicates that roofing is able to withstand severe exposure to fire originating from sources outside the building. Class “B” Fire Resistance: Fire-resistance rating that indicates roofing material is able to withstand moderate exposure to fire originating from sources outside the building. Class B Door: A fire resistant rating applied by the Underwriters Laboratories Classification for a door having a 1 to 1 1/2 hour rating. Class “C” Fire Resistance: Fire-resistance rating that indicates roofing material is able to withstand light exposure to fire originating from sources outside the building. Class I Landfill: A landfill permitted to accept hazardous waste. Class II Biosafety Cabinet: Class II biological safety cabinets are designed to have air flow drawn around the operator, into the front of the cabinet to protect the person. Inside the cabinet a downward laminar flow of HEPA-filtered air protects the product being handled. There are several types of Class II biosafety cabinets. Class II Landfill: A landfill permitted to accept designated and municipal solid waste. Class III Landfill: A landfill permitted to accept only non-hazardous municipal solid waste. Class 100 Environment: A room environment maintained by air conditioning and filtration so that fewer than 100 particles of size 1 μm or larger are found in a cubic foot of air. Class 1 Permit Modification: Minor change to the Hazardous Waste Facility Permit (HWFP). May be implemented 30 days after the California Environmental Protection Agency Department of Toxic Substances Control (DTSC) has been notified of and concurs with the proposed change. Requires documented public and DTSC notification Class 1* Permit Modification: Change to HWFP that requires prior written approval from DTSC before implementation. Within seven days after DTSC has been notified, persons on the facility’s mailing list must be notified of the proposed change by publishing the change in a major newspaper with general circulation. Proof of Class 2 Permit Modification. Change to HWFP that requires notification of persons of the facility’s mailing list within seven days before or after notifying DTSC of the proposed change by publishing the proposed change in a major newspaper with general circulation and allowing a 60-day comment period. The permittee shall hold a public Classification: May also be referred to as the action to sort out particles by various groups or to other established criteria. CLC: Canada Labour Code. Clean Air Act: Originally passed in 1963, although the 1970 version of the law is the basis of today’s U.S. national air pollution program. The 1990 Clean Air Act Amendments are the most far-reaching revisions of the 1970 law, and are usually referred to as the 1990 Clean Air Act. Clean Air Delivery Rate (CADR): Clean Air Delivery Rate (CADR) is the rate at which an air filtration unit delivers clean air back into a room. CADR is a standard of measurement that describes the number of cubic feet of clean air per minute an air cleaner can provide. Clean-Air Design: This is a vacuum cleaner design where the airflow that carries the dirt passes through most of the filtering system before it reaches the motor where it passes through the fans (and may also be used to cool the motor). With this design there is usually an additional filter installed after the motor to filter any carbon dust produced by the motor itself. This type of design increases motor longevity, produces excellent suction and eliminates fan breakage and motor damage common in "dirty air" traditional upright vacuums. Clean-Air Device, Laminar Flow: A laminar flow enclosure, clean bench, clean work station, wall or suspended ceiling module, or other device (except a cleanroom) which incorporates a HEPA filter(s) and a fan(s) to supply laminar flow clean air to a controlled work space. Clean and Tune (C&T): A procedure performed on a heating system by a licensed furnace service technician to maximize the appliance efficiency using existing hardware. The C&T is usually preceded by a combustion efficiency test to assess whether other conditions exist requiring extensive furnace work. The C&T can involve a variety of activities to upgrade the efficiency and safe operation of the heating system. These can include pilot and burner adjustment, adjustment of ventilation and combustion, check and reset controls, inspect filters, lubricate motors, flush low water cut-off, check operation of steam and water relief valves, check thermostat, check safety valve, and check thermocouple. Clean Bench: See Clean-air device, laminar flow. Cleanability: The ability of a filter element to withstand repeated cleanings, while maintaining adequate dirt capacity. Cleanout: A plug in a trap or drain pipe that provides access for the purpose of clearing an obstruction. Cleanout (Plumbing): A drain fitting, usually a wye or a tee, with a removable plug to permit inspection and access for an auger or snake. Clean Pressure Drop: The pressure loss across the filter element determined under steady state flow conditions using a clean test fluid across a clean filter element. Differential pressure (drop) across measured in pounds per square inch at rated flow on new elements with clean product. Clean Room: A facility or enclosure in which air content and other conditions (such as temperature, humidity, and pressure) are controlled and maintained at a specific level by special facilities and operating processes and by trained personnel. Cleanroom Garments: Special clothing designed to protect cleanroom environments from contaminants released by workers. Special apparel includes non-shedding gowns or coveralls, head covers, face masks, gloves, footwear or shoe covers. Clean Water Act (CWA): Federal legislation enacted in 1972 which requires every state to submit a biennial report to the EPA, describing the quality of its surface, ground and marine waters. Clean Work Station: A clean-air device such as a bench or similar enclosure, characterized by having its own supply of filtered air. CleanEffects™ (also Trane CleanEffects™): Trane Air filtration system that removes 99.98% of airborne allergens down to .1 microns from the filtered air, making it 100 times more effective that a standard 1" filter. Cleaner-Burning Gasoline: Gasoline fuel that results in reduced emissions of carbon monoxide, nitrogen oxides, reactive organic gases, and particulate matter, in addition to toxic substances such as benzene and 1,3-butadiene. Cleaning: The process of removing unwanted substances and putting them in their proper place. Cleanliness Level: A measure of relative freedom from contaminants. Cleanout: A plug in a trap or drain pipe that provides access for the purpose of clearing an obstruction. Cleanroom: A room (facility) in which the air supply, air distribution, filtration of air supply, materials of construction, and operating procedures are regulated to control airborne particle concentrations to meet appropriate cleanliness levels. Clear Sky: Cloudless Sky – clear sky in this context has two separate meanings. In the radiation Tables clear sky refers to days producing the mean maximum monthly daily global radiation on a horizontal surface. These days on average contain some cloud but the precise cloud amount is not known. In the temperature Tables, the term clear skies refers to summaries of measured temperature data for days when the mean total amount of cloud during hours of daylight was less then 2/8. Night-time temperature data for such days are related to the same 'clear' days i.e. night-time cloud cover was not taken into account. Clear Sky (Standard): Cloudless sky for which the relative luminance distribution is described in CIE Publication N022 (1973). Clearance: The maximum cylinder volume on a working side of the piston, minus the piston displacement volume per stroke. It is usually expressed as a percentage of the displace volume. Clearance Pocket: An auxiliary volume that may be opened to the clearance space for increasing the clearance, usually temporarily, to reduce the volumetric efficiency of the compressor. Cleat: A wedge-shaped piece (usually of metal) which serves as a support or check. A strip fastened across something to give strength or hold something in position. Clerestory: A window that is placed vertically (or near vertical) in a wall above one's line of vision to provide natural light in a building. Clevis: A device for mounting cylinders. Climate Chamber: A chamber usually in a laboratory in which the environmental conditions can be changed by the experimenter, used to investigate the effects of the thermal environment on subjects. Climate Control: The control of the indoor climate. Climatuff® Compressor: The Trane Climatuff® Compressor was the world’s first successful heat pump compressor. To this day it's the only compressor Trane uses in its residential systems. It’s well known for its superior durability, its low noise levels, and high efficiency. Clinical Trials: Research programs conducted with patients to evaluate a new medical treatment, drug or device. The purpose of clinical trials is to find new and improved methods of treating different diseases and special conditions. Clip Ties: Sharp cut metal wires that protrude out of a concrete foundation wall that at one time held the foundation form panels in place. Clo Unit: a unit for the insulating effect of clothing on a person. 1 clo = 0.155 (K.m2)/W. Closed-Circuit: See closed-circuit SCBA. Electrical circuit in which electrons are flowing. Closed-Circuit Respirators: See closed-circuit SCBA. Closed-Circuit SCBA: A type of atmosphere-supplying respirator where used (exhaled) air is treated, supplemented and re-circulated for breathing; see also oxygen re-breathing, oxygen-generating, self-contained breathing apparatus, open-circuit SCBA. Closed Cut Valley: A method of valley treatment in which shingles from one side of the Closed Loop: Any piping system where the internal fluids are sealed from their surroundings. Commonly referred to as glycol loops. Closed Loop System: A system in which distilled water, antifreeze, and/or corrosion inhibitors are circulated through a collector and storage tank in a closed loop. Heat picked up from the collector by the circulating fluid is transferred to the storage tank through the closed loop or other heat exchangers. Closed Mouth Technique: A method for inhaling medicine from a metered dose inhaler. The open mouth technique is the preferred method. (See open mouth technique) Closed Weave: Fabrics are constructed such that, when viewing the fabric perpendicular to its surface, you cannot see through the holes formed by the interwoven fibers. Closed weave fabrics tend to be thicker and stiffer than open weaves. Closet Auger: A flexible rod with a curved end used to access the toilet's built-in trap and remove clogs. Closet Bend: A curved fitting that connects the closet flange to the toilet drain. Closet Bolts: Bolt whose head is fitted to a closet flange and protrudes up through a toilet base. A nut is tightened around it on the toilet base. Two (or four) bolts serve one toilet. Closet Flange: An anchoring ring secured to the floor. The base of the toilet is secured to this ring with bolts. Closure: The placement of signs at an area of a public beach that informs the public an area is closed to swimming and water contact. These signs should indicate the nature of the public health concern (e.g., sewage spill), and should, by nature of their language, color, and design, enable the recreating public to differentiate from advisories provided by posting. Closure is envisioned to occur when health risks are considered greater than those associated with posting, as with sewage spills or at areas at which monitoring results show that multiple indicator organism standards are exceeded, for both single sample and 30-day average values. Clothing Insulation: The effective insulation of clothing worn characterized as a single layer covering the whole body surface; measured in Clo Units or K.m2/W. Clothing Surface Temperature: Average temperature of the surface of the clothes for use in heat. Clutch, Magnetic: Clutch built into automobile compressor flywheel, operated magnetically, which allows pulley to revolve without driving compressor. CMAQ: Congestive Mitigation and Air Quality Improvement Program. CMAQ was introduced in the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA). It is set up to provide Federal funding to help fulfill Clean Air Act mandates in areas that do not meet ambient air quality standards or may have trouble meeting those standards (nonattainment or maintenance areas).CMM: Cubic Meters per Minute. A measurement of airflow rate. CMU (Concrete Masonary Unit): Building block fill used in exterior walls between windows and floors, and windows and columns. CNG: ACRONYM – Compressed natural gas, primarily methane. CNS: The Central Nervous System consists of the brain and spinal cord, in vertebrates. CO: Carbon monoxide. CO2: Carbon dioxide. Coal Tar: A viscous liquid mixture of hydrocarbon compounds, derived, along with coke, from the destructive distillation of coal. Coal Tar Pitch: A bituminous material, which is a by-product from the coking of coal. It is used as the waterproofing material for tar and gravel built-up roofing. Coalbed Methane: Most coal deposits contain natural gas adsorbed onto the coal. This gas is known as coal bed methane. Coalescer: Mechanical device which unites discrete droplets of one phase prior to being separated from a second phase. Can only be accomplished when both phases are immiscible. Coalescing: A term that means “to come together;” a process in which small oil aerosols come in contact with the fibres in a filter media, unite with other collected aerosols, and combine into droplets heavy enough to be gravitationally drained away. Action of uniting small droplets of one liquid preparatory to its being separatedfrom another liquid. Coalescing Filter: A mechanical filter with a drain, which removes liquid oil, water, and Coastal Waters: Waters of the Pacific Ocean outside of enclosed bays and estuaries that are within the territorial limits of California. Coating: A layer of any substance such as paint, lacquer, or varnish applied over a surface for protection. Immersion of filter media in a solution to provide the fibers with a coating that will lubricate and thereby reduce self-abrasion. Code: The local, state, or national rules that govern safe installation and service of systems and equipment for the purpose of safety of the public and trade personnel. Code of Ethics: Ethical standards of conduct for home inspectors. Coefficient of Conductivity: Measure of the relative rate at which different materials conduct heat. Coefficient of Discharge: The ratio of the measured relieving capacity to the theoretical relieving capacity. Code of Federal Regulations (CFR): Codification of all regulations promulgated by federal government agencies. Coefficient of Haze (COH): A measurement of the quantity of dust and smoke in the atmosphere in a theoretical 1,000 linear feet of air. A COH of less than three is considered clean air and more than five is of some concern. COH readings of 20 or more can occur in urban areas. Co-efficient of Performance (COP): A heat pump or air conditioner's output in watt-hours of heat moved divided by watt-hours of electrical input. Congener: Any particular member of a class of chemical substances, such as dioxins. A specific congener is denoted by a unique chemical structure, for example 2,3,7,8-TCDD. Cogeneration: Also known as Combined Heat and Power (CHP). COHS Regulations: Canada Occupational Health and Safety Regulations. Coil: A snake-like piece of copper tubing surrounded by rows of aluminum fins that clamp tightly to the tubing and aid in heat transfer. Coil Electrical: A conductor wound in a series of turns. Coil Refrigeration: Any cooling element made of piping. Coking: Input definition. Cold: The word used to describe heat at lower levels of intensity. Cold Applied: Products that can be applied without heating. These are in contrast to products which need to be heated to be applied. Cold Differential Test Procedure: Actual gage pressure on the test stand that includes correction factors for temperature, pulsation, vibration, constant back pressure, etc. Cold Evaporation: See “Cool Mist.” Cold Interstate Waters: Streams and lakes having a range of temperatures generally suitable for trout and salmon. Cold-Method or Lap Cement: Special multipurpose adhesive for low-sloped, cold-applied roof construction. Bonds 19” selvedge, mineral surface and cap sheets to the underlayment. Doubles as an adhesive on 2” selvedge lap of mineral-, granule- or smooth-surfaced roofing. Available in both summer and winter grades. Cold Patch: In roofing, a roof repair done with cold-applied material. Cold Process Adhesive: Mastic prepared with SBS modifiers to adhere laps, flashing and joints of built-up or low-slope roofing without hot-mopping or torching equipment. Cold Site: A computer facility available for use in the event of a disaster. Generally this is just a room; computers, power, and cooling systems must be installed. Cold Start: Starting a compressor from a state of total shutdown. Usually done with “local” control at the compressor. May be done with “remote” control, but only advised with “heavy” instrumentation and monitoring accessories.
Coliform (also Referred to as Total Coliform): All facultative anaerobic, gram negative, non-spore forming, rod shaped bacteria that ferment lactose with gas and acid formation within 48 hours at 35◦C. Coliform bacteria are found in soil, water, fruit, vegetables, grains, flowering plants and trees, and in the intestinal tract of animals. Collapse: An inward structural failure of a filter element which can occur due to abnormally high pressure drop (differential pressure) or resistance to flow. Collapse Pressure: The minimum differential pressure that an element is designed to withstand without permanent deformation. The outside-in differential pressure that causes the structure of a filter medium failure of a filter element. Collar: In roofing, a conical metal cap flashing used in conjunction with vent pipes or stacks usually located several inches above the plane of the roof for the purpose of shedding water away from the base of the vent. Collar Beam: In carpentry, a tie that keeps the roof from spreading. They serve to stiffen the roof structure. Connects similar rafters on opposite sides of roof. Collar Tie: A horizontal board attached perpendicular to rafters. Collection Efficiency: Percentage of contaminate collected. Collective Dose Equivalent and Collective Effective Dose Equivalent: Sums of the dose equivalents or effective dose equivalents to all individuals in an exposed population within 80 km (50 miles) of the radiation source. These are evaluated by multiplying the dose received by an individual at each location by the number of individuals receiving that dose, and summing over all such products for locations within 80 km of the source. They are expressed in units of person-rem or person-sievert. The collective EDE is also referred to as the “population dose.” Colloid: Very small, insoluble non-diffusible solid or liquid gelatinous particles that remain suspension in a surrounding liquid. Solids usually on the order of 0.2 μm or less. Colloids: Miniature cells peculiar to meats, fish, and poultry which disrupted, cause food to become rancid. Low temperatures minimize this action. Colony: A discrete growth usually discernable by the naked eye; this term is usually used in reference to growth originating from a single spore or cell. Color Rendering Index (CRI): A measurement of a light source's ability to render colors the same as sunlight. CRI has a scale of 0 to 100. Color Temperature: A measurement of the warmness or coolness of a light source in the Kelvin temperature scale. Column: A vertical building support usually made of wood or steel. Colour Rendering: Effect of (not necessarily white) light on the color appearance of objects compared to their colour appearance under a reference illuminant. Colour Rendering Index (R): Measure of the degree to which the psychophysical colour of an object illuminated by the test illuminant conforms to that of the same object illuminated by the reference illuminant, suitable allowance having been made for the state of chromatic adaptation. Column: A vertical building support usually made of wood or steel. In architecture: A perpendicular supporting member, circular or rectangular in section, usually consisting of a base, shaft, and capital. In engineering: A vertical structural compression member which supports loads acting in the direction of its longitudinal axis. Combination Doors or Windows: Combination doors or windows are used over regular openings. They provide winter insulation and summer protection and often have self storing or removable glass and screen inserts. This eliminates the need for handling a different unit each season. Combination Foundations: Buildings constructed with more than one foundation type; e.g., basement/crawlspace or basement/slab-on-grade. Combined Heat and Power: Combined heat and power (CHP), also known as cogeneration, is an efficient, clean, and reliable approach to generating power and thermal energy from a single fuel source. CHP is not a specific technology but an application of technologies to meet an energy user's needs. CHP systems achieve typical effective electric efficiencies of 50 to 80 percent — a dramatic improvement over the average efficiency of separate heat and power. Since CHP is highly efficient, it reduces traditional air pollutants and carbon dioxide, the leading greenhouse gas associated with climate change. Combustion Analyzer: A device used to measure steady-state efficiency of combustion heating units. Combustion Chamber: The area inside the heat exchanger where the flame burns. Any wholly or partially enclosed space in which combustion takes place. Combustion Gases: The gaseous byproducts of the combustion of a fuel. Combustion Test: This test is performed to determine the efficiency at which a heating appliance is operating at steady state. The actual tests or sequence of tests may vary in conjunction with the type of testing equipment used or the type of heating appliance being tested. Persons performing these tests must be extremely familiar with the testing equipment being used and must be trained in conducting the tests. In some states, a license is required to perform such tests. Comfort Air Conditioning: Comfort air conditioning systems are designed for the comfort of people, not the protection of computer-based electrical systems. Unlike people, computers generate dry (sensible) heat, but not humidity. Only about 60-70% of a comfort system’s total capacity is dedicated to the removal of sensible heat, while 30-40% is for dehumidification. With a large percentage of their total capacity devoted to the removal of moisture, comfort systems can lower room humidity far below acceptable standards. A larger comfort system is required to obtain the same sensible capacity as a precision cooling system. Comfort Chart: A chart showing effective temperatures with dry-bulb temperatures and humidities (and sometimes air movement), by which the effects of various thermal conditions on human comfort may be compared. Comfort™ Coil (also Evaporator Coil or Indoor Coil): Part of an indoor air unit, it functions with the air conditioner or heat pump outdoors to cool and condition indoor air that flows over it by drawing out heat and moisture. Comfort Line: A line on the comfort chart showing relation between the effective temperature and the percentage of adults feeling comfortable. Comfort Temperature (neutral temperature): 1)The temperature (or environment) judged by a population to be neutral on the ASHRAE scale, or Comfortable, Neither Warm Nor Cool on the Bedford scale: assumed by most workers in the field to be the desired temperature or 2) the temperature at which the greatest number of people feel comfortable. Comfort Vote: The subjective response given by a subject on a comfort scale such as the ASHRAE or Bedford scales (see above). Comfort Zone: The range of temperature within which a subject will feel comfortable, though not necessarily neutral. ComfortHeat: Carrier’s exclusive ComfortHeat technology accurately predicts the need for heating while cutting temperature swings in half. ComfortHeat Pump System: ComfortHeat Pump System is Carrier’s exclusive heat pump system that provides significantly warmer supply air from the registers for enhanced occupant comfort. Commensal: Commensal means a microorganism that normally lives in close contact with a human or animal without causing any harm. This would include many of the bacteria normally present on a person’s or animal’s skin or intestine. Commercial Airflows: The airflow (between 300 and 500 FPM) at which most non-residential, non-HEPA HVAC systems are designed to operate. Commercial Energy Customer: A commercial energy customer refers to non-industrial customers occupying retail space or office buildings. Commissioning: Start-up of a building that includes testing and adjusting HVAC, electrical, plumbing, and other systems to assure proper functioning and adherence to design criteria. Commissioning also includes the instruction of building representatives in the use of the building systems. A systematic process that begins in the design phase of a new or remodeled building and includes the testing and fine-tuning of HVAC, electrical, plumbing and other systems, to assure proper functioning and adherence to design criteria throughout construction. Commissioning also includes preparation of the systems operations manuals and instruction of the building maintenance personnel. The process of inspecting, starting up, and testing new or refurbished equipment; refer to CSA Z180 for the definition. Committed Dose Equivalent: The committed dose equivalent is the time integral of the dose-equivalent rate in a particular tissue that will be received by an individual following an intake of radioactive material into the body by inhalation, ingestion or dermal absorption. For adults the committed dose is usually the dose received over 50 years. For children, the committed dose is usually calculated from the age of intake to age 70 years. For these age groups the term ‘integrated dose equivalent’ is used. Committed Effective Dose Equivalent (CEDE): The committed dose equivalents to various tissues or organ in the body each multiplied by an appropriate tissue-weighing factor and then summed. The conventional unit for committed effective dose equivalence (CEDE) used by federal and state agencies within the United States is the rem. The international scientific (SI) unit of committed effective dose equivalent is called a sievert (Sv). One Sv is the same as 100 rem. Common Rafter: Rafter that extends from the top plate to the ridge. Generally set 12, 16, or 24 inches apart. Compatibility: Relation to the non-reactivity of filter materials with a substance to be filtered. Compatible: Two or more substances, which can be mixed or blended without separating, reacting, or affecting either material adversely. Compensator: An expansion joint designed to take up thermal expansion. Competitive Markets: Until recently, most consumers received generation, transmission, and distribution services from one local utility company. As a regulated monopoly, the utility was given an exclusive franchise to provide electricity to consumers in any particular community. Rates were set, and consumers had little choice but to pay that rate. In recent years, however, many states have restructured their electricity industry and are now allowing consumers to choose from among competing electricity suppliers. In these states with retail competition, sellers of electricity obtain power by contracting with various generation sources and setting their own price. Consumers in these states have the opportunity to choose their energy provider and purchase products based on the price or type of power supplied to their home or business. Some consumers are exercising this choice and switching to accredited "green power" resources. In states that have not restructured their electricity markets, consumers interested in purchasing renewable energy now have the option to participate in green pricing programs offered by their local utility. Component: A permanently installed or attached fixture, element or part of a system. Composite Board: An insulation board which has two different insulation types laminated together in 2 or 3 layers. Composite Cylinder: A type of SCBA cylinder using a combination of resin and fibre wrapping materials to strengthen an inner aluminum liner.
Compound Gauge: Instrument for measuring pressure both above and below atmospheric pressure. Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA): Administered by EPA, this program, also known as Superfund, requires private parties to notify the EPA after the release of hazardous substances or conditions that threaten to release hazardous substances, and undertake short-term removal and long-term remediation. Compressed Breathing Air (CBA): Normal air that is processed by a compressed breathing air system to meet purity requirements; refer to CSA Z180 for the applicable purity requirements. Compressed Breathing Air Pipeline: That part of the compressed breathing air system that consists of all components immediately following and connected to a source of compressed breathing air or a purification system; comprises the complete assembly of piping, fittings, control equipment, service outlets, etc, required to distribute compressed breathing air to the point of use in either permanent or temporary installations. Compressed Breathing Air System: An assembly of various components such as air intake, ambient air system, compressor, purification system, receiver, cylinder, proportioning system, piping, fittings, compressed breathing air pipeline, control equipment, required to produce and/or deliver compressed breathing air to the point of use. Compression: Term used to denote increase of pressure on a fluid using mechanical energy. Compressor: An air-moving device used to raise the pressure of gases above standard atmospheric pressure. Compressor, Reciprocating: A type of compressor used in dehumidifiers and air conditioners that compresses the refrigerant by use of a piston and cylinder design. Compressor, Rotary: A type of heavy-duty compressor used in commercial grade dehumidifiers that compresses refrigerant by use of a rotary screw design. Composite Board: An insulation board which has two different insulation types laminated together in 2 or 3 layers. Composition of Air: A colorless, odorless, tasteless gas. A mixture of individual gases. The gaseous mixture surrounding the earth. Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA): Also known as Superfund, this Federal law authorizes U.S. EPA to respond directly to releases of hazardous substances that may endanger public health or the environment. Compressed: To reduce the volume of, by or as if by pressure. Compressed Air: Air under pressure greater than that of the atmosphere. Compressed Air Challenge: A public/private initiative to promote the efficiency of compressed air in the U.S. Compressed Gas: (a) A gas or mixture of gases having a pressure exceeding 40 psia at 70°F in a container, or (b) A gas or mixture of gases having a pressure exceeding 104 psia in a container at 130°F, regardless of the pressure at 70°F, or Stanford Laboratory Standard & Design Guide. (c) A liquid or mixture of liquids having a vapor pressure exceeding 40 psia at 100°F as determined by UFC Standard No. 9-5. Compressed Natural Gas (CNG): (See alternative fuels.) Compressibility: A factor expressing the deviation of gas from the laws of hydraulics. Degree of physical change in filter cake particles when subjected to normal pressures. Compressibility Factor Z: Is the ratio of the actual volume of the gas to the volume determined according to the perfect gas law. Compression Adiabatic: Compression in which no heat is transferred to or from the gas during the compression process. Compression Band: Stainless steel band sewn into the end of a bag to provide a surface to clamp against in the baghouse. Compression Efficiency: Is the ratio of the theoretical work requirement to the actual work required to be performed on the gas for compression and delivery. Compression Fitting: Used to join or connect pipes and conduit by causing a ring to compress against the connecting tube when tightening with a wrench. Compression Gasket: A gasket designed to function under compression. Compression Gauge: An instrument used to measure positive pressure. Compression Isothermal: Is a compression in which the temperature of a gas remains constant. Compression Ratio: The ratio of the absolute discharge pressure to the absolute inlet pressure. Compression Set: The permanent deformation of a material after removal of the compressive stress. Compression Valve: A type of valve that works by raising or lowering a stem. Water passes through the valve by turning the faucet handle, which causes the stem to drop or rise. Compression Web: A member of a truss system which connects the bottom and top chords and which provides downward support. Compressor: This is the heart of an air conditioning or heat pump system. It is part of the outdoor unit and pumps refrigerant in order to meet the cooling requirements of the system. This component is responsible for compressing the refrigerant and then pumping around the system. A motorized pump that compresses the gaseous refrigerant and sends it to the condenser where heat is released. A device used to compress air for mechanical or electrical power production, and in air conditioners, heat pumps, and refrigerators to pressurize the refrigerant and enabling it to flow through the system.
Computer Control: May be “local” using a micro-processor or “remote” using a PC (Personal Computer) or “larger” computer. Only recommended where large “swings” in system (process) demand amplitude may occur. Very effective where “load shaping” is an important consideration. “Heavy” monitoring and instrumentation accessories required for it to be efficient and effective. Usually not necessary where system demand is predominantly constant. Computer Controlled Air/Fuel Management System: Maintains the air/fuel ratio in the correct operating range needed for complete combustion without an excess of either air or fuel, resulting in low engine-out emissions and maximized catalyst performance. Concealed Nail Method: Application of roll roofing in which all nails are driven into the underlying course of roofing and covered by a cemented, overlapping course. Nails are not exposed to the weather. Concentration: The quantity of one constituent dispersed in a defined amount of another. The relative amount of a substance mixed with another substance. Examples are 5 ppm of carbon monoxide in air and 1 mg/l of iron in water. The amount of one ingredient contained in a mixture; the measurement of this can be expressed as a percentage, or in other units such as ppm or mg/m3. Concrete Block: A hollow concrete ‘brick’ often 8”x8”x16” in size. Often used in low rise commercial and some residential construction. The original design and use is attributed to the architect Frank Lloyd Wright. Concrete Board: A panel made out of concrete and fiberglass usually used as a tile backing material. Concrete Board or Wonderboard (TM): A panel made out of concrete and fiberglass usually used as a tile backing material. Concrete Grout: A mixture of 3/8-inch pea gravel, sand, cement and water which is poured into the cells of concrete-block walls to reinforce them. Concrete Plain: Concrete either without reinforcement, or reinforced only for shrinkage or temperature changes. Condemn: Remove from service and make unfit for future use. Condensate: Vapor that liquefies due to the lowering of its temperature to the saturation point. The liquid that separates from a vapor during condensation. Condensate Pump: A small pump used to pump condensate to a higher level. Condensate Receiver: A tank for catching returning condensate water from a steam heating system. Condensation: Condensed liquid — in this context beads, drops or a film of water (or frost) that accumulates on the inside of facade elements, roofs or floors (usually on windows) when warm, moisture air from the interior reaches a point where the temperature (the 'dew point') no longer permits the air to sustain the moisture it holds. Condense: When a gas turns into a liquid as it cools, it condenses. Condensation is the opposite of evaporation. When a gas condenses into a liquid it releases heat. Condense Comb: Comb-like device used to straighten the metal fins on condensers or evaporators. Condenser: A device that changes a vapor into a liquid. Accomplished by exposing a tube containing vapor to air or by passing the tube through a water jacket.
Condenser Coil (or Outdoor Coil): In an air conditioner, the coil dissipates heat from the refrigerant, changing the refrigerant from vapor to liquid. In a heat pump system, the coil absorbs heat from the outdoors. Condenser Fan: The fan that circulates air over the air-cooled condenser. There are two fans blades in every air conditioner. The condenser fan is for circulating the air over the condenser coils to dissipate the heat from the refrigerant. The other circulates the air over the evaporator coils and back into the room or building. Condenser, Water Cooled: Heat exchanger that transfers heat to water.
Condition: The visible and conspicuous state of being of an object. Conditioned: Intentionally heated or cooled areas of a building. Conditioned Air: Air that has been heated, cooled, humidified, or dehumidified to maintain an interior space within the “comfort zone.” (Sometimes referred to as “tempered” air.) Conditions, Convenants, and Restrictions (CC and Rs): The standards that define how a property may be used and the protections the developer makes for the benefit of all owners in a subdivision. Conductance: The property of a material to conduct some energy form like heat or electricity. Conduction: The transfer of heat energy through a material (solid, liquid, or gas) by the motion of adjacent atoms and molecules without gross displacement of the particles. Conduction is the transfer of heat through a material by molecular movement. Reducing heat loss through conduction can include the installation insulation in wall, ceiling, and floor cavities, insulation of hot water tanks, creating thermal breaks in window and door framing, and sealing of bypasses and other sources of air movement. The flow of heat from one part of a substance to another part. A piece of iron with one end placed in a fire will soon become warm from end to end due to the transfer of heat by the actual collision of the air molecules. Conductive Heat Transfer: Process of conduction through a material. Materials like copper or silver are good conductors. Conductivity: A measure of the ability of an aqueous solution to carry an electric current (see Electrical Conductivity). The rate at which heat is transmitted through a material. The ability of as material to transfer heat. Conductor: In roofing, a pipe for conveying rainwater from the roof gutter to a drain, or from a roof drain to the storm drain; also called a leader, downspout, or downpipe. In electrical contracting, a wire through which a current of electricity flows, better known as an electric wire. Conductor (Electrical): Anything that conducts or carries electricity. Conduit: A hollow pipe casing through which electric lines run. Conduit (Electrical): Tubing used to protect wiring. Confined Groundwater: A body of groundwater overlain by material sufficiently impervious to prevent free hydraulic connection with overlying groundwater. Confined Space: An enclosed space or partially enclosed space that: is not designed or intended for human occupancy except for the purpose of performing work; that has restricted means of access; and that may become hazardous to a person entering it; this Confining Bed: A body of impermeable or distinctly less permeable material stratigraphically adjacent to [i.e. above or below] one or more aquifers. Conformal Coating: Material coating to protect fan from harsh environmental conditions. Conformity: A demonstration of whether a federally-supported activity is consistent with the State Implementation Plan (SIP) – per Section 176 (c) of the Clean Air Act. Transportation conformity refers to plans, programs, and projects approved or funded by the Federal Highway Administration or the Federal Transit Administration. General conformity refers to projects approved or funded by other federal agencies. Congestion Management Program: A state-mandated program (California Government Code Section 65089a) that requires each county to prepare a plan to relieve congestion and reduce air pollution. Conjunctivitis: Pronunciation (kon-jŭnk′ti-vī′tis). Inflammation of the conjunctiva. Connector: The mating device that is inserted into the coupler of a quick coupler and locked to complete the connection. Also referred to as plug or nipple. Console: An area from where operators control the rest of the facility. Constant Air Volume System: Air handling system that provides a constant air flow while varying the temperature to meet heating and cooling needs. Constituent: A component or attribute of waste that is detectable. Constraints: Factors in the physical or social environment which prevent people from taking actions to achieve thermal comfort. Constrictor: Tube or orifice used to restrict flow of a gas or a liquid. Construction Contract: A legal document which specifies the details of a construction project. A good construction contract will include: (1.)The contractors registration number. (2.)A statement of work quality such as ‘Standard Practices of the Trades’ or ‘according to Manufacturers Specifications.’ (3.)A set of blue prints or plans. (4.)A set of specifications. (5.)Any allowances. (6.)A construction timetable including starting and completion dates. (7.)A fixed price for the work, or a time and materials formula. (8.)A payment schedule. (9.)A written warrantee. (10.)A clause which outlines how any disputes will be resolved. Construction Drywall: A type of construction in which the interior wall finish is applied in a dry condition, generally in the form of sheet materials or wood paneling as contrasted to plaster. Construction, Frame: A type of construction in which the structural parts are wood or depend upon a wood frame for support. In codes, if masonry veneer is applied to the exterior walls, the classification of this type of construction is usually unchanged. Construction Loan: A loan provided by a lending institution specifically to construct or renovate a building. Construction Waste Recycling: The separation and recycling of recoverable waste materials generated during construction and remodeling. Packaging, new material scraps, old materials, and debris all constitute potentially recoverable materials. Consumer Products: Products such as hairspray, detergents, cleaning compounds, polishes, lawn and garden products, personal care products, and automotive specialty products which are part of our everyday lives and, through consumer use, may produce volatile organic air emissions which contribute to air pollution. Contact Dermatitis: A rash or inflammation of the skin caused by contact with biological or chemical substances. The reaction may be an immunologic response or a direct toxic effect of the substance. Among the more common causes of a contact dermatitis reaction are detergents, metals, chemicals in rubber gloves and condoms, certain cosmetics, plants such as poison ivy, and topical medications.
Contained Space: A building, building zone, room, micro-environment, glovebox, or other enclosure in which air supply and exhaust are controlled. Containment: The combination of personal practices, procedures, safety equipment, laboratory design, and engineering features to minimize the exposure of workers to hazardous or potentially hazardous agents. Contaminant: Any physical, chemical, biological, or radioactive substance that can adversely affect air, water or soil. Any unwanted substance present in or on a material or any surface within a clean zone. Foreign matter carried in the air, gas or fluid to be filtered out. Includes air borne dirt, metallic particles produced by wear of moving parts of the air compressor, rust from metal pipelines. Contaminant Capacity: The weight of a specified artificial contaminant that must be added to the influent to produce a given differential pressure across a filter at specified conditions. Used as an indication of relative service life. Contaminant Failure: Any loss of performance due to the presence of contamination. Two basic types of contamination failure are: Perceptible – gradual loss of efficiency or performance, and Catastrophic – dramatic, unexpected failure. Contaminate: To reduce the level of a clean zone or material by the addition of contaminants. Contiguous Zone: The portion of ocean waters between the state and federal territorial limits. Continuing Education: Ongoing education, often a requirement for membership in a home inspection association. For example, NACHI’s Continuing Education Policy. Continuity Tester: An electrical tool used to identify and diagnose a circuit as either open or closed. Continuous Emission Monitor (CEM): A type of air emission monitoring system installed to operate continuously inside of a smokestack or other emission source. Continuous Emission Monitoring Systems (CEMS): Machines that measure, on a continuous basis, pollutants released by a source. The 1990 Clean Air Act requires continuous emission monitoring systems for certain large sources. Continuous Phase: Basic product flowing through a filter or filter separator, which continues on through the system after being subjected to solids and/or other liquid separation. Continuous Sampling Device: An air analyzer that measures air quality components continuously. (See also Integrated Sampling Device.) Contractor: An individual licensed to perform certain types of construction activities. In most states, the generals contractor’s license and some specialty contractor’s licenses don’t require of compliance with bonding, workmen’s compensation and similar regulations. Some of the specialty contractor licenses involve extensive training, testing and/or insurance requirements. There are various types of contractors: General Contractor – responsible for the execution, supervision and overall coordination of a project and may also perform some of the individual construction tasks. Most general contractors are not licensed to perform all specialty trades and must hire specialty contractors for such tasks, e.g. electrical, plumbing. Remodeling Contractor – a general contractor who specializes in remodeling work. Specialty Contractor – licensed to perform a specialty task e.g. electrical, side sewer, asbestos abatement. Sub Contractor – a general or specialty contractor who works for another general contractor. Contraindication: Any condition which indicates that a particular course of treatment (or exercise) would be inadvisable or cause harm. Control: Any device to start stop regulate or protect a system. Control Area: A building or portion of a building within which the exempted amounts of hazardous materials are allowed to be stored, dispensed, used or handled. Control Circuit: A circuit whose work is switching a power circuit or opening an automatic valve. Control Equipment: An assembly of mechanical or electrical components such as regulators, valves, alarms, recorders, or switches, used to operate a compressed breathing air system; used to ensure the production and delivery of compressed breathing air in the quality and quantity required. Control Joint: A control joint controls or accommodates movement in the surface component of a roof. Control, Low Pressure: A Safety device connected to low-pressure side of system. Control, Refrigerant: A device used to regulate flow of liquid refrigerant into evaporator. Control System: All of the components required for the automatic control of a process variable. Control Techniques Guidelines (CTG): Guidance documents issued by U.S. EPA that define reasonably available control technology (RACT) to be applied to existing facilities that emit excessive quantities of air pollutants; they contain information both on the economic and technological feasibility of available techniques. Control Technology; Control Measures: Equipment, processes or actions used to reduce air pollution. The extent of pollution reduction varies among technologies and measures. In general, control technologies and measures that do the best job of reducing pollution will be required in the areas with the worst pollution. For example, Best Available Control Technology/Best Available Control Measures (BACT/ BACM) are required in serious nonattainment areas for particulates, a criteria air pollutant. A similar high level of pollution reduction will be achieved with maximum achievable control technology (MACT) that will be required for sources releasing hazardous air pollutants.
Control Velocity: The air velocity at the face of an enclosing hood to retain a contaminant generated within the hood. Controlled Coughing: A technique in which the cough comes from deep within the lungs and has just enough force to loosen and carry mucus through the airways without causing them to narrow and collapse. Controlled coughing saves energy and oxygen. Controlled Breathing: A method of consciously reducing air used by forcing exhalation from the mouth and allowing natural inhalation through the nose. Controlled Drug: Controlled drugs are those listed in the schedule to the Narcotic Control Regulations of the Controlled Drugs & Substances Act, and can only be obtained by a licensed doctor, dentist or veterinarian, or by special permit for research purposes. The list includes the barbiturates, and many opiates. Controlled Environment: An environment in which parameters such as temperature, pressure, humidity, contaminant level and so forth are controlled within specified limits. Controlled Ventilation: Ventilation brought about by mechanical means through pressure differentials induced by the operation of a fan. Controller: A group of controls and circuits used to accurately and automatically operate a device. Controller Medications: Medications taken daily on a long-term basis that are useful in getting persistent asthma under control and in maintaining control. They include anti-inflammatory agents and long-acting bronchodilators. Anti-inflammatory agents, particularly inhaled corticosteroids, are the most effective controller medications. Controller medications are also sometimes called prophylactic, preventive, regular preventive, or maintenance medications. Convection: Heat transfer between a surface and adjacent fluid (usually air or water) and by the flow of fluid from one place to another. See also Forced convection, Natural convection. Is a means of transferring heat through mass flow. Also the transfer of heat within a fluid by movements within the fluid.
Convector: An agency of convection. In heat transfer, a surface designed to transfer its heat to a surrounding fluid largely or wholly by convection. The heated fluid may be removed mechanically or by natural convection (gravity convector). Such a surface may or may not be enclosed or concealed. Apparatus for heating, in which the heat is passed on to the room by convection, due to natural air movement sometimes helped by a fan. Convective Heat Transfer: Process of heat transport by convective flow. With free convection the flow is caused by temperature differences in the liquid or gas. For example the air inside double glazing transports heat due to natural convection; the glazing layer on the inside is warmer than the one on the outside; the air inside the cavity moves because of this temperature difference and transports the heat. With forced convection energy is transferred due to a mechanically driven gas flow or liquid flow. Convective Loop: A structural heat loss resulting from temperature differences between the inside and outside wall surfaces causing an air movement loop within the wall cavity. This condition can be present when a stud cavity has no insulation. Air in the cavity is heated near the interior surface of the wall, rises, circulates back toward the exterior siding, falls, re-circulates back to the warm side, is re-heated, and so on. Conventional Loan: A mortgage loan not insured by a government agency (such as FHA or VA). Convertibility: The ability to change a loan from an adjustable rate schedule to a fixed rate schedule. Convolution: On a bellow type air actuator, that part of the flexible member forming an annular protrusion larger than the O.D. of the end retainers or bead rings. Cool Mist: This is a method of humidification that uses a variety of methods to release moisture into room air without heating the water. Cool mist humidifiers include evaporative, impeller and ultrasonic types. Coolant: Fluid cooling agent. Cooler: Heat exchanger which removes heat from a substance. Cooling: The process of active heat extraction for the benefit of climate control. see also direct cooling, evaporative cooling, indirect cooling, regenerative cooling, surface cooling. Cooling Capacity: The quantity of heat that a cooling appliance is capable of removing from a room in one hour. A measure of the ability of a unit to remove heat from an enclosed space. COP - Coefficient of Performance of a heat pump means the ratio of the rate of useful heat output delivered by the complete heat pump unit (exclusive of supplementary heating) to the corresponding rate of energy input, in consistent units and under operating conditions. Cooling Coils: A cooling element through which treated gas or liquid is passed, exchanging thermal energy with the air surrounding it for purposes of heating or cooling. Cooling Degree Day: A value used to estimate interior air cooling requirements (load) calculated as the number of degrees per day (over a specified period) that the daily average temperature is above 65 degrees Fahrenheit (or some other, specified base temperature). The daily average temperature is the mean of the maximum and minimum temperatures recorded for a specific location for a 24 hour period. Cooling Effect, Sensible: Difference between the total cooling effect and the dehumidifying effect, usually in watts. Cooling Effect, Total: Difference between the total enthalpy of the dry air and water vapour mixture entering the cooler per hour and the total enthalpy of the dry air and water vapour mixture leaving the cooler per hour , expressed in watts. Cooling Element: Heat transfer surface containing refrigeration f1uid where refrigerating effect is desired. Cooling Load: The amount of cooling required to keep a building at a specified temperature during the summer, usually 78° Fahrenheit, regardless of outside temperature. The thermal energy extracted from a building to maintain a pre-determined indoor set point temperature. Cooling Medium: Any substance whose temperature is such that it is used, with or without a change of state, to lower the temperature of other bodies or substances. Cooling Range: In a water cooling device, the difference between the average temperatures of water entering or leaving the device. Cooling Tower: A cooling water supply system. There are two different types – Open and closed loop systems. A large device mounted on roofs, consisting of many baffles over which water is pumped in order to reduce its temperature. Cooling Water: Water for condensation of refrigerant; condenser water. Water used to reduce temperature. COP (Coefficient of Performance): COP compares the heating capacity of a heat pump to the amount of electricity required to operate the heat pump in the heating mode. COPD: Chronic Obstructive Pulmonary Disease. Coped: Removing the top and bottom flange of the end(s) of a metal I-beam. This is done to permit it to fit within, and bolted to, the web of another I-beam in a “T” arrangement. Coped Joint: Cutting and fitting woodwork to an irregular surface. Coping: A construction unit placed at the top of the parapet wall to serve as a cover for the wall. Coping Joint: The intersection of a roof slope and an exterior vertical wall. Copper Pipe Types: Type K has the heaviest or thickest wall and is generally used underground. It has a green stripe. Type L has a medium wall thickness and is most commonly used for water service and for general interior water piping. It has a blue stripe. Type M has a thin wall and many codes permit its use in general water piping installation. It has a red stripe. Copper Plating: Abnormal condition developing in some units in which copper is electrolytically deposited on some compressor surfaces. Cor Pulmonale: Enlargement of the right side of the heart. Cor pulmonale weakens the heart and causes increased shortness of breath and swelling in the feet and legs. Patients who have chronic COPD with low oxygen levels may develop this condition. Corbel: The triangular, decorative and supporting member that holds a mantel or horizontal shelf. Corbel Out: To build out one or more courses of brick or stone from the face of a wall to form a support for timbers. Cord Reel: See “Cord Winder.” Cord Retractor: See “Cord Winder.” Cord Release: On vacuum cleaners that do not have cord rewinders, the power cord is generally wrapped around cord holders that come in a variety of design configurations. A Quick Cord Release is a design that releases all the wrapped cord with a single adjustment so the user does not have to unwrap each turn of cord from the holders. This is a convenient and time saving feature. Sometimes referred to as a “Quick Cord Release.” Cord Winder: A feature on vacuum cleaners and other appliances that retracts the cord onto a reel or spool inside the vacuum cleaner. Typically activated by the touch of a button there are also cord winders that retract automatically during cleaning. Also referred to as a “Cord Retractor,” “Cord Reel,” “Cable Winder,” etc. Core: A small section cut from any material to show internal composition. Commonly refers to a perforated tube, which serves as the center of a filter cartridge (element).
Core Temperature (deep body temperature): The temperature of the internal organs of the body, especially the brain, on the basis of which the thermoregulatory system of the body is controlled. Core Yarn: Used in filtration with fiberglass or synthetic yarn. Spun or texturized yarns are twisted around a filament (core) yarn, adding yarn strength and stability. Corner Bead: A strip of formed sheet metal, sometimes combined with a strip of metal lath, placed on corners before plastering to reinforce them. Also, a strip of wood finish three-quarters-round or angular placed over a plastered corner for protection. Corner Boards: Used as trim for the external corners of a house or other frame structure against which the ends of the siding are finished. Corner Braces: Diagonal braces at the corners of frame structure to stiffen and strengthen the wall. Cornerite: Metal-mesh lath cut into strips and bent to a right angle. Used in interior corners of walls and ceilings on lath to prevent cracks in plastering. Cornice: A horizontal projecting course on the exterior of a building, usually at the base of the parapet. In residential construction, the overhang of a pitched roof at the cave line, usually consisting of a facie board, a soffit for a closed cornice, and appropriate moldings. Cornice Return: The portion of the cornice that returns on the gable end of a house. Coronal Discharge: A type of air purifier that uses ozone to clean the air, a Coronal Discharge device is sometimes referred to as a “thunderstorm in a box”. The air inside a coronal discharge device is charged with between 5,000 and 10,000 volts of electricity. The massive shock causes unstable bonds to form between single atoms of oxygen (O) and Oxygen molecules (O2). Ozone then attacks any airborne particles in the surrounding area (O3). Correlation: An indication of the strength of the relationship between two variables characterized by the correlation. Correlative: Having a mutual or reciprocal relation that is that the existence of one necessarily implies the existence of the other. Corresponding Values: values of parameters corresponding to other parameters. Corrosion: Action or effect of eating away gradually. This can occur through oxidation, the action of strong acids, or caustic alkali. The deterioration of metal by chemical or electrochemical reaction resulting from exposure to weathering, moisture, chemicals or other agents or media. Oxidation or galvanic action of metal. Corrosive: A chemical agent that reacts with a surface, causing it to deteriorate or wear away. A substance that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact. For example, a substance is considered to be corrosive if, when tested on the intact skin of albino rabbits by the method described by the U.S. Department of Transportation in Appendix A to 49 CFR Part 173, it destroys or changes irreversibly the structure of the tissue in 4 hours. This term does not refer to action on inanimate surfaces. Corrugated: Folded or shaped into parallel ridges or furrows so as to form a symmetrically wavy surface. Corticosteroids: A type of medication used to reduce inflammation. These drugs mimic a substance produced naturally by the adrenal glands. In asthma, these drugs are often taken through an inhaler for long-term control. They may also be taken orally or given intravenously for a short time if asthma symptoms become out of control. Cosmic Radiation: Radiation with very high energies originating outside the earth’s atmosphere; it is one source contributing to natural background radiation. Cost Breakdown: A breakdown of all the anticipated costs on a construction or renovation project. Cost-Effectiveness: The cost of an emission control measure assessed in terms of dollars-per-pound, or dollars-per-ton, of air emissions reduced. Cost Plus Contract: See Time and Materials Contract. Coulomb: The quantity of electricity transferred by an electric current of one ampere in one second. Counter EMF: Tendency for reverse electrical flow as magnetic field changes in an induction coil. Counter Flashing: The formed metal secured to a wall, curb, or roof top unit to cover and protect the upper edge of a base flashing and its associated fasteners. This type of flashing is usually used in residential construction on chimneys at the roofline to cover shingle flashing and to prevent moisture entry. Counteractant: A substance used to neutralize the malodor. Counter Flow: Flow in opposite direction. Counterflow: Flow in the opposite direction in heat exchange between two fluids; the coldest portion of one meeting the coldest portion of the other. Counterfort: A foundation wall section that strengthens (and is generally perpendicular to) a long section of foundation wall. Coupling: In plumbing, a short collar with only inside threads at each end, for receiving the ends of two pipes which are to be fitted and joined together. A right/left coupling is one used to join 2 gas pipes in limited space. Course: A single layer of brick or stone or other building material. Cove Molding: A molding with a concave face used as trim or to finish interior corners. Covenants: Rules usually developed by a builder or developer regarding the physical appearance of buildings in a particular geographic area. Typical covenants address building height, appropriate fencing and landscaping, and the type of exterior material (stucco, brick, stone, siding, etc) that may be used. Coverage: Amount of weather protection provided by the roofing material. Depends on number of layers of material between the exposed surface of the roofing and the deck; i.e. single coverage, double coverage, etc. CPAP (Continuous Positive Airway Pressure) Machine: A breathing machine that provides pressure to keep the upper airways open during breathing. This machine is often used for patients with obstructive sleep apnea. CPM: ACRONYM – Cycles per minute – a unit of measure of the frequency of any vibration. CPR (cardiopulmonary resuscitation): a first-aid method to restore breathing and heart action through mouth-to-mouth breathing and chest compression. CPU: Central Processing Unit. This is the computational brain of any computer system. The CPU does all the calculations and number crunching for the system. A CPU farm is a cluster of multiple CPUs. CPVC (Chlorinated Polyvinyl Chloride): Rigid plastic pipe used in water supply systems where code permits. CRAC: Computer Room Air Conditioner. Cracking: To subject petroleum oil to heat for breaking down into lighter products. Input definition. CRAH: Computer Room Air Handler. Crankcase Heater: This is the electric resistance heater installed on compressor crankcases to boil off liquid refrigerant that may have combined with compressor oil. Many newer cooling systems do not require crankcase heaters, however heat pumps do require crankcase heaters. Crankshaft Seal: Leak proof joint between crankshaft and compressor body. Crater: Pit in the surface of concrete resulting from cracking of the mortar due to expansive forces associated with a particle of unsound aggregate or a contaminating material, such as wood or glass. Crawl Space: The area beneath floors that provides access to utilities and other services. Other options are basements and slabs on grade. Crazing: A series of hairline cracks in the surface of weathered materials, having a web-like appearance. Also, hairline cracks in pre-finished metals caused by bending or forming (see Brake Metal). Credit Rating: A report ordered by a lender from a credit agency to determine a borrower's credit habits.
CRI: Carpet and Rug Institute (www.carpet-rug.com), the national trade association representing the carpet and rug manufacturing industry with technical services, member services, governmental and consumer affairs, and public relations. CRI provides green label approval to products that improve indoor air quality. Cricket: A peaked saddle construction at the back of a chimney to prevent accumulation of snow and ice and to deflect water around the chimney. Cripple Stud: Short stud used as support in wall openings that replaces a normal 93 inch or 96 inch stud. Cripple Walls: In a wood-frame house, the section of wall under the house between the concrete foundation and the floor joists. Also called crawl space walls.
Criteria: (a) A standard, rule, or test by which something can be judged; measure of value, (b) Specific levels of water quality which, if reached, are expected to render a body of water suitable for its designated beneficial use. Criteria Air Pollutant: An air pollutant for which acceptable levels of exposure can be determined and for which an ambient air quality standard has been set. Examples include: ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and PM10 and PM2.5. The term “criteria air pollutants” derives from the requirement that the U.S. EPA must describe the characteristics and potential health and welfare effects of these pollutants. The U.S. EPA and CARB periodically review new scientific data and may propose revisions to the standards as a result. Criteria Air Pollutants: The 1970 amendments to the Clean Air Act required EPA to set National Ambient Air Quality Standards for certain pollutants known to be hazardous to human health. EPA has identified and set standards to protect human health and welfare for six pollutants ozone, carbon monoxide, total suspended particulates, sulfur dioxide, lead, and nitrogen oxide. The term, "criteria pollutants" derives from the requirement that EPA must describe the characteristics and potential health and welfare effects of these pollutants. It is on the basis of these criteria that standards are set or revised. Critical Level: The amount of a count (Lc) or final measurement of a quantity of an analyte at or above which a decision is made that the analyte is definitely present (Lc ≈ MDA/2). Critical Operating Pressure: Pressure above which filtration or separation equipment may produce reduced efficiency or fails to function properly. Critical Pressure: Is the saturation pressure at the critical temperature. It is the highest vapor pressure that the liquid can exert. Critical Reach: The section of a stream extending either from the point of diversion or, if the project includes an impoundment, the most upstream point of the impoundment to the point of return. Critical Speed: Rotative speeds at which rotating machinery-axial or screw lobe-pass through unbalanced operation. Critical Vibration: Vibration which is noticeable and harmful to structure. Crock: Used in the ground to hold water for pumping sump pumps. Cross Tee: Short metal “T” beam used in suspended ceiling systems to bridge the spaces between the main beams. Cross-Bridging: Diagonal bracing between adjacent floor joists, placed near the center of the joist span to prevent joists from twisting. Cross Charged: Two fluids which together create a desired pressure-temperature properties. Cross-Contamination: A condition created when a drill hole, boring, or improperly constructed well forms a pathway for fluid movement between a saturated zone which contains pollutants and a formerly separated saturated zone containing ground water. Also where portable and sanitary services are interconnected. Cross Section: A view of a building component drawn or imagined by cutting through the component. Cross Tee: Short metal “T” beam used in suspended ceiling systems to bridge the spaces between the main beams. Cross Ventilation: Flow of air through a building caused by wind-generated pressure drop across it. Crosscutting: Cutting across the wood grain; to crosscut a board is to cut across its width. Crossflow (tangential flow) Filtration: A filtration system in which the feed stream flows across the filter media and exits as a retentate stream. The retentate stream is recycled to merge into the feed stream, while a portion of it passes through the filter media, resulting in concentration of the feed stream (referred to as concentrate). Crosshead Assembly: The assembly connecting the crankcase and connecting rod to the cylinder head and piston rod for translating circular to linear motion. Crosshead Compressor: A compressor belonging to the group of displacement reciprocating compressors. Crosshead Loading: The tensile or compressive loading on the crosshead assembly with compressive piston rod loading on the outward stroke and tensile piston rod loading on the inward stroke. Crown Molding: A molding used on cornice or wherever an interior angle is to be covered. Crude Bitumen: A mixture of hydrocarbons that is semi-solid. Alberta's oil sands are rich in bitumen, and are the world's largest source. Crude Oil: A naturally occurring mixture of hydrocarbons trapped in underground rock formations. Crude oil can be refined into many products such as transportation fuels (gasoline and diesel), heating oil, asphalt, petrochemicals and plastics.
Cryptococcosis: A disease caused by the fungus Cryptococcus neoformans; may infect lungs, central nervous system, skin, and lining of body cavity. CSA: ACRONYM – Canadian Standards Association. A not-for-profit association that develops standards to enhance public safety and health and preserve the environment. CSBG: Community Services Block Grant: The Community Services Block Grant (CSBG) is federal, anti-poverty block grant which funds the operations of a state-administered network of local agencies. This CSBG network consists of more than 1,100 agencies that create, coordinate and deliver programs and services to low-income Americans in 96% of the nation's counties. Most agencies in the CSBG network are Community Action Agencies (CAAs), created through the Economic Opportunity Act, a predecessor of the CSBG. Community representation and accountability are hallmarks of the CSBG network, where agencies are governed by a tri-partite board. This structure consists of elected public officials, representatives of the low-income community, and appointed leaders from the private sector. Because the CSBG funds the central management and core activities of these agencies, the CSBG network is able to mobilize additional resources to combat the central causes of poverty. CT: Computed Tomography, also called Computerized Axial Tomography (CAT) scanning, is a diagnostic medical tool that uses x rays to obtain a series of cross-section images of the body which are then integrated using a computer. CTC: Canadian Transport Commission. CTD: ACRONYM – Approach temperature. Usually the difference between cooling water temperature in to compressed air temperature out of an inter-cooler or after-cooler. Sometimes used to define oil cooler efficiency (cooling water temperature in to oil temperature out). Cubic Feet per Minute (CFM): CFM. An airflow measurement of volume. Cubic Feet per Second (cfs): The rate of flow passing any point equal to the volume of one cubic foot of water every second. One cfs is equal to 7.48 gallons per second; 448.8 gallons per minute; 646,317 gallons per day (86,406 cubic feet per day). Cupola: A small dome at the peak of a pitched roof. Cupping: A type of warping that causes boards to curl up at their edges. Cupro-Nickel: 90% copper / 10% nickel alloy which has high corrosion resistance to water containing salt, sulphur, chlorides and other dissolved minerals. Curb: A short wall or masonry built above the level of the roof that provides a means of flashing the deck equipment. Curb Roof: A roof with an upper and lower set of rafters on each side, the under-set being less inclined to the horizon than the upper; a mansard roof. Curie (Ci): Unit of measurement of radioactivity, defined as the amount of radioactive material in which the decay rate is 3.7 × 1010 disintegrations per second or 2.22 × 1012 disintegrations per minute; one Ci is approximately equal to the decay rate of 1 gram of pure radium. Curing: In concrete application, the process in which mortar and concrete harden. The length of time is dependent upon the type of cement, mix proportion, required strength, size and shape of the concrete section, weather and future exposure conditions. The period may be 3 weeks or longer for lean concrete mixtures used in structures such as dams or it may be only a few days for richer mixes. Favorable curing temperatures range from 50 to 70 degrees Fahrenheit. Design strength is achieved in 28 days. Curing (Paint): The process of paint bonding to a surface. Curing and drying are not the same. Curing Agent: One part of a multi-part sealant which, when added to the base, will cause the base to change its physical state by chemical reaction between the two parts. Current: The flow of electrons through a conductor.
Curtain Drain: A ditch sometimes filled with gravel and a drain tile which diverts storm and drain water away from a structure. Curtain Wall: A thin wall, supported by the structural steel or concrete frame of the building independent of the wall below. Also a metal (most often aluminum) framing system on the face of a building containing vision glass panels and spandrel panels made of glass, aluminum, or other material. Curtailment Programs: Restrictions on operation of fireplaces and woodstoves in areas where these home heat sources make major contributions to pollution. Curtain Wall: A wall between columns and beams that supports no weight but its own. Customer Certification: A final determination concerning program eligibility based on income and ownership, resulting in the customer's receipt or denial of WAP benefits. Cut Off: A piece of roofing membrane consisting of one or more narrow plies of felt usually mopped in hot to seal the edge of insulation at the end of a day’s work. Cut-In Brace: Nominal 2-inch-thick members, usually 2x4s, cut in between each stud diagonally. Cutaneous: Pertaining to or affecting the skin. Cutback: In roofing, basic asphalt or tar which has been “cut back” with solvents and oils so that the material become fluid. Cut Off: A piece of roofing membrane consisting of one or more narrow plies of felt usually mopped in hot to seal the edge of insulation at the end of a day's work. Cutoff Valves: Valves used to shut water off, generally located under sinks or behind bathtub and shower access panels. They cut off hot and/or cold water at the source without cutting all water off throughout the house. Cut In Cut Out Pressure: The settings on a pressure switch used to either load or unload the air compressor on a constant speed application, or start or stop the compressor on a start/stop application. The cut out pressure is also known as the maximum pressure, or the point at which there is no air being delivered. The cut in pressure is referred to as the minimum pressure, or the pressure that the system is allowed to fall to before air volume is required. CWS: Canada Wide Standards. Standards for environmental contaminants or issues developed with the participation of industry, municipal, environmental, health and aboriginal groups after the Environment Ministers have jointly agreed on priorities for these standards. Cycle Time: Amount of time for a compressor to complete one cycle. Cyclone: A type of separator for removal of larger particles from an exhaust gas stream. Gas laden with particulates enters the cyclone and is directed to flow in a spiral causing the entrained particulates to fall out and collect at the bottom. The gas exits near the top of the cyclone. An air pollution control device that removes larger particles – generally greater than one micron – from an air stream through centrifugal force. Cyclone Collector: A device that uses centrifugal force to remove large particles from polluted air. Cyclone Separator: A means of purifying an air stream by using both gravitational and centrifugal forces. Cyclonic Action: A method of vacuum cleaner filtration that separates soils from the airflow by making the air stream spin, subjecting it to centrifugal force, which throws the dirt and debris out of the air. Cyclonic filtration is used in a variety of “bagless” type vacuum cleaners. Dyson has developed an advanced cyclonic filtration system that represents the state-of-the-art in this technology. Cylinder: The piston chamber in a compressor or actuator. Cylinder Crown: The dome-shaped top portion of a cylinder, from the top to the beginning of the side wall; see cylinder shoulder. Cylinder Head: Plate or cap which encloses compression end of compressor cylinder. Cylinder Liner: The aluminum core lining the interior of composite cylinders. Cylinder Neck: The top portion of a cylinder, containing the threads, face and O-ring. Cylinder Neck Ring: A steel ring around the neck of a cylinder to reinforce a threaded area. Cylinder O-Ring: An elastomeric ring placed in the groove between the cylinder neck face and valve face to form an airtight seal. Cylinder, Refrigerant: A cylinder used to store refrigerant. Cylinder Shoulder: The top part of a cylinder from its neck to its side wall; see cylinder crown. Cystitis: Inflammation of the urinary bladder. Cytokines: Cytokines are a group of compounds that are secreted primarily from white blood cells when the immune system is activated. They stimulate both the humoral and cellular immune responses, and activate other cells of the immune system. Some of the cytokines are called interleukins. Cytolytic: Cyto – cells; lysis – destruction. Cytolytic ability or capacity refers to the ability to destroy cells, by a microorganism, for example. Cytostatic: Inhibiting or suppressing cellular growth and multiplication. A cytostatic agent. See Cytotoxic drugs. Cytotoxics Cleanroom: A special cleanroom with HEPA filtration of supply and exhaust air for the installation of cytotoxic drug safety cabinets in pharmaceutical applications. See AS 2639. Cytotoxic Drug Safety Cabinets: Laminar flow safety cabinets that protect operators, environment, products and service personnel. Cabinets are described in AS 2567 and have different HEPA filter systems from Class II biological safety cabinets - that are unsuitable for work with toxic or carcinogenic agents. Cytotoxic Drugs: Drugs that control or kill neoplastic cells; used in chemotherapy to kill cancer cells; all have unpleasant side effects that may include nausea, vomiting, hair loss and suppression of bone marrow function. Cytotoxic Drugs in Class II Cabinets – Hazards: Class II cabinets used with cytotoxic drugs in animal studies pose a potential risk to service personnel. Class II cabinets are unsuitable for use with cytotoxic drugs and other toxic chemicals, as these materials cannot be deactivated by fumigation prior to service procedures. See AS 2567 and AS 2647. |
||||||||||||||||||||||||||||||||||||||||
Creosote: A highly flammable tar-like oily deposit that is produced by slow-burning fires.