Glossary

The combination of an effect and an exposure that may constitute a threat of harm to human health or the environment.

Under the Clean Air Act, a series of listed items which may constitute pollution if emitted above regulator specified levels.

A subcategory of solid waste (defined under RCRA to include solids, liquids, contained gases and sludges) that are defined to be hazardous because:
(1) they meet characteristics of corrosiveness, reactivity, flammability, or contain extractable constituents that are defined as toxic; or
(2) they are listed solid wastes from specific or non-specific sources that may contain potentially hazardous constituents.

The overall system comprising generation, transport, storage, treatment, and disposal of hazardous wastes.

Calculations made to determine the amount of heat generated upon the combustion of fuels and wastes and the amount of cooling water needed to cool and quench the reaction upon completion.

A device specifically designed to transfer heat between two physically separated fluids.

Latent heat involved in changing between the solid and the liquid states.

Latent heat involved in the change between liquid and vapour states.

A refrigerating system employed to transfer heat into a space or substance. The condenser provides the heat while the evaporator is arranged to pick up heat from air, water, etc. By shifting the flow of air or other fluid, a heat pump system may also be used to cool the space.

The lightest of the noble gases.
Detector: Katharometer or acoustic analyser.
Advantages: Non-toxic, stable, detectable at less than 0.5% in air.
Disadvantages: Low M.W. low density. tendency for small molecules to be absorbed into porous materials. It may be mobile enough to diffuse through thin partitions where air molecules could not pass.

(1) Impervious to air.

(2) Resistant to penetration by air.

Frequency, in cycles per second, of AC power. Named after H.R. Hertz, the German scientist who discovered electrical oscillations.

Frequency of sound expressed by cycles per second.

The maximum desirable, or safe, temperature; or
 an alarm given when this temperature is exceeded.

Application of a voltage greater than the working voltage to test the adequacy of motor insulation. Often referred to as high potential test or "hi-pot".

A device that encloses, captures, or receives emitted contaminants.

A device for measuring air flow rates.

A device to add moisture to air.

Abbreviation for Heating, Ventilation, and Air-Conditioning.

A system concerned with the temperature, humidity, cleanliness, and distribution of air.

Ventilating systems designed primarily to control temperature, humidity, odors, and air quality.

A unit operated for the express purpose of burning hazardous wastes.

An instrument for measuring water vapour content of the air.

An instrument for measuring the humidity of the air using the property of expansion/contraction of certain materials (e.g. hair) with relative humidity.

Hertz.