Acute Exposure Guideline Levels are described as “level 1”, “level 2”, or “level 3”. What is the difference?
AEGL “levels” are dictated by the severity of the toxic effects caused by the exposure. All levels are expressed as parts per million or milligrams per cubic meter of a substance which it is predicted that the general population could experience, including susceptible individuals:
Level 1: Notable discomfort or certain asymptomatic non-sensory effects. Effects are not disabling and are transient and reversible upon cessation of exposure.
Level 2: Irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape.
Level 3: life-threatening health effects or death