Action Level —The exposure level to which corrective action must be taken

ACGIH — American Conference of Governmental Industrial Hygienists

Ambient — An encompassing atmosphere: environment

Ceiling — The concentration that should not be exceeded during any part of the working exposure. It may be assessed by sampling over a period of time that should not exceed 15 minutes.

CDC — Center for Disease Control

Diffusion — The process whereby particles of liquids, gases, or solids intermingle as the result of their spontaneous movement

Dosimeter — A device for measuring doses of radiation or hazardous vapors

Excursion — One complete movement of expansion and contraction of the lungs

JCAHO — Joint Commission on Accreditation of Healthcare Organizations

NFPA — National Fire Protection Association

NIOSH — National Institute for Occupational Safety and Health

OSHA — Occupational Safety and Health Administration

PPM — Parts Per Million

Passive — Without the intervention of mechanical devices

PEL — Permissible Exposure Limit

STEL — Short Term Exposure Limit: The concentration to which it is believed that workers can be exposed continuously for a short period of time without suffering adverse effects.

TLV — Threshold Limit Value: The point at which a physiological effect begins to be produced