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Appendix F: Glossary and Acronyms

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Appendix F: Glossary and Acronyms Appendix F: Glossary and Acronyms ACGIH — American Conference of materials, windows, and walls, that enclose Governmental Industrial Hygienists. the internal space. ASHRAE — American Society of Building-Related Illness — Diagnosable Heating, Refrigerating, and Air-Condition- illness whose symptoms can be identified ing Engineers. and whose cause can be directly attributed ASTM — American Society for Testing to airborne building pollutants (e.g., and Materials. Legionnaire’s disease, hypersensitivity pneumonitis). Air Cleaning — An IAQ control strategy to remove various airborne particulates CFM — Cubic feet per minute. and/or gases from the air. The three types CO — Carbon monoxide. of air cleaning most commonly used are CO2 — Carbon dioxide. particulate filtration, electrostatic precipita- Ceiling Plenum — Space below the tion, and gas sorption. flooring and above the suspended ceiling Air Exchange Rate — Used in two ways: that accommodates the mechanical and 1) the number of times that the outdoor air electrical equipment and that is used as replaces the volume of air in a building per part of the air distribution system. The unit time, typically expressed as air space is kept under negative pressure. changes per hour; 2) the number of times Commissioning — Start-up of a building that the ventilation system replaces the air that includes testing and adjusting HVAC, within a room or area within the building. electrical, plumbing, and other systems to Antimicrobial — Agent that kills micro- assure proper functioning and adherence to bial growth. See “disinfectant,” “sani- design criteria. Commissioning also tizer”, and “sterilizer.” includes the instruction of building BRI — See “Building-Related Illness.” representatives in the use of the building Biological Contaminants — Agents systems. derived from or that are living organisms Conditioned Air — Air that has been (e.g., viruses, bacteria, fungi, and mammal heated, cooled, humidified, or dehumidi- and bird antigens) that can be inhaled and fied to maintain an interior space within can cause many types of health effects the “comfort zone.” (Sometimes referred to including allergic reactions, respiratory as “tempered” air.) disorders, hypersensitivity diseases, and Constant Air Volume Systems — Air infectious diseases. Also referred to as handling system that provides a constant “microbiologicals” or “microbials.” air flow while varying the temperature to Breathing Zone — Area of a room in meet heating and cooling needs. which occupants breathe as they stand, sit, Dampers — Controls that vary airflow or lie down. through an air outlet, inlet, or duct. A Building Envelope — Elements of the damper position may be immovable, building, including all external building manually adjustable, or part of an auto- mated control system. Glossary and Acronyms 153 Diffusers and Grilles — Components of Hypersensitivity Diseases — Diseases the ventilation system that distribute and characterized by allergic responses to diffuse air to promote air circulation in the animal antigens. The hypersensitivity occupied space. Diffusers supply air and diseases most clearly associated with grilles return air. indoor air quality are asthma, rhinitis, and Disinfectants — One of three groups of hypersensitivity pneumonitis. Hypersensi- antimicrobials registered by EPA for tivity pneumonitis is a rare but serious public health uses. EPA considers an disease that involves progressive lung antimicrobial to be a disinfectant when it damage as long as there is exposure to the destroys or irreversibly inactivates causative agent. infectious or other undesirable organisms, IAQ — Indoor air quality. but not necessarily their spores. EPA IPM — Integrated pest management. registers three types of disinfectant Indicator Compounds — Chemical products based upon submitted efficacy compounds, such as carbon dioxide, whose data: limited, general or broad spectrum, presence at certain concentrations may be and hospital disinfectant. used to estimate certain building condi- EPA — United States Environmental tions (e.g., airflow, presence of sources). Protection Agency. MCS — See “Multiple Chemical Sensitiv- ETS — Environmental tobacco smoke. ity.” Environmental Agents — Conditions MSDS — Material Safety Data Sheet. other than indoor air contaminants that Make-up Air — Air brought into a cause stress, comfort, and/or health building from the outdoors through the problems (e.g., humidity extremes, drafts, ventilation system that has not been lack of air circulation, noise, and over- previously circulated through the system. crowding). Microbiologicals — See “Biological Ergonomics — Applied science that Contaminants.” investigates the impact of people’s physical environment on their health and Multiple Chemical Sensitivity — A term comfort (e.g., determining the proper chair used by some people to refer to a condition height for computer operators). in which a person is considered to be sensitive to a number of chemicals at very Exhaust Ventilation — Mechanical low concentrations. There are a number of removal of air from a portion of a building views about the existence, potential causes, (e.g., piece of equipment, room, or general and possible remedial actions regarding area). this phenomenon. Gas Sorption — Devices used to reduce NIOSH — National Institute for Occupa- levels of airborne gaseous compounds by tional Safety and Health. passing the air through materials that extract the gases. The performance of NTIS — National Technical Information solid sorbents is dependent on the airflow Service. rate, concentration of the pollutants, Negative Pressure — Condition that presence of other gases or vapors, and exists when less air is supplied to a space other factors. than is exhausted from the space, so the air HEPA — High efficiency particulate pressure within that space is less than that arrestance (filters). in surrounding areas. HVAC — Heating, ventilation, and air- OSHA — Occupational Safety and Health conditioning system. Administration. 154 Appendix F PELs — Permissible Exposure Limits building occupants experience acute health (standards set by OSHA). and/or comfort effects that appear to be PM — Preventive Maintenance. linked to time spent in a particular build- ing, but where no specific illness or cause Plenum — Air compartment connected to can be identified. The complaints may be a duct or ducts. localized in a particular room or zone, or Positive Pressure — Condition that exists may be spread throughout the building. when more air is supplied to a space than Soil Gases — Gases that enter a building is exhausted, so the air pressure within that from the surrounding ground (e.g., radon, space is greater than that in surrounding volatile organics, pesticides). areas. Stack Effect —Pressure-driven airflow Psychosocial Factors — Psychological, produced by convection as heated air rises, organizational, and personal stressors that creating a positive pressure area at the top could produce symptoms similar to poor of a building and a negative pressure area indoor air quality. at the bottom of a building. The stack RELs — Recommended Exposure Limits effect can overpower the mechanical sys- (recommendations made by NIOSH). tem and disrupt ventilation and circulation Radiant Heat Transfer — Radiant heat in a building. transfer occurs when there is a large differ- Static Pressure — Condition that exists ence between the temperatures of two when an equal amount of air is supplied to surfaces that are exposed to each other, but and exhausted from a space. At static are not touching. pressure, equilibrium has been reached. Re-entrainment —Situation that occurs Sterilizer — One of three groups of anti- when the air being exhausted from a build- microbials registered by EPA for public ing is immediately brought back into the health uses. EPA considers an antimicro- system through the air intake and other bial to be a sterilizer when it destroys or openings in the building envelope. eliminates all forms of bacteria, fungi, SBS — See “Sick Building Syndrome.” viruses, and their spores. Because spores Sanitizer — One of three groups of anti- are considered the most difficult form of a microbials registered by EPA for public microorganism to destroy, EPA considers health uses. EPA considers an antimicro- the term sporicide to be synonymous with bial to be a sanitizer when it reduces but “sterilizer.” does not necessarily eliminate all the mi- TLVs — Threshold Limit Values (guide- croorganisms on a treated surface. To be a lines recommended by ACGIH). registered sanitizer, the test results for a TVOCs — Total volatile organic com- product must show a reduction of at least pounds. 99.9% in the number of each test microor- Tracer Gases — Compounds, such a ganism over the parallel control. sulfur hexafluoride, which are used to Short-circuiting — Situation that occurs identify suspected pollutant pathways and when the supply air flows to exhaust regis- to quantify ventilation rates. Tracer gases ters before entering the breathing zone. To may be detected qualitatively by their odor avoid short-circuiting, the supply air must or quantitatively by air monitoring equip- be delivered at a temperature and velocity ment. that results in mixing throughout the space. VAV — Variable air volume system. Sick Building Syndrome — Term some- VOCs — See “Volatile Organic Com- times used to describe situations in which pounds.” Glossary and Acronyms 155 Variable Air Volume System — Air products made with organic chemicals. handling system that
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