(IDLH) The maximum air concentration of a chemical substance from which a healthy worker could escape within a 30-minute exposure without irreversible adverse health effects or escape-impairing health conditions (dizziness, unconsciousness, and so forth) . The level is set by the national institute for occupational safety and health. This acute air exposure standard is often used to estimate adverse effects on nearby human populations that may be caused by spills or other short-term accidental releases of toxic chemicals.
