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Protecting emergency response personnel from chemicals of high priority by deriving immediately dangerous to life or health (IDLH) values using refined methodology.

Maier-A; Parker-AL; Dotson-G
Toxicologist 2009 Mar; 108(1):311
The National Institute for Occupational Safety and Health (NIOSH) has been investigating methods to improve the derivation of Immediately Dangerous to Life or Health (IDLH) values. IDLH values are 30-minute atmospheric concentrations of any toxic, corrosive, or asphyxiant substance that, via inhalation exposure, poses an immediate threat to life or would cause immediate or delayed irreversible adverse health effects or would interfere with an individual's ability to escape from a dangerous atmosphere in the event of a respirator failure. We developed a process to prioritize IDLH development for high priority chemicals of specific interest to emergency response personnel (i.e., chemical terrorism agents or industrial chemicals subject to emergency or uncontrolled releases). The prioritization process included weighted scores to account for metrics of exposure potential, toxicity, and a variety of secondary considerations (such as toxicity data availability and existence of other acute exposure guidance values). We evaluated the impact of a refined weight of evidence approach described in our prior work on methods for developing IDLH values. The refined approach was applied to 20 case study chemicals from the list of agents identified by the prioritization process. The resulting preliminary IDLH values and the rationale for their derivation is presented and contrasted to the IDLH values that would have been developed using a default IDLH calculation approach. Lessons learned from these case studies are used to inform further refinements in the IDLH derivation methods as they apply to chemicals of interest to homeland security applications and emergency preparedness.
Biological-factors; Chemical-hypersensitivity; Chemical-indicators; Chemical-properties; Emergency-responders; Employee-exposure; Exposure-assessment; Exposure-levels; Exposure-methods; Lung-irritants; Medical-personnel; Occupational-exposure; Occupational-hazards; Occupational-health; Rescue-workers; Respiratory-hypersensitivity; Respiratory-system-disorders; Risk-factors; Risk-analysis; Toxic-effects; Toxic-materials; Toxins
Publication Date
Document Type
Fiscal Year
Issue of Publication
NIOSH Division
Source Name
The Toxicologist. Society of Toxicology 48th Annual Meeting and ToxExpo, March 15-19, 2009, Baltimore, Maryland
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division