3M Corporation put together a respiratory protection guide (download link at end of this article) that contains a wealth of information for OH&S professionals including:
- Immediately Dangerous to Life or Health (IDLH) levels
- Odor Thresholds
- Occupational Exposure Levels (OELs)
- Respiratory Protection Selection Guide
IDLH’s are published by NIOSH and “refers to the acute respiratory exposure that poses an immediate threat of loss of life, immediate or delayed irreversible adverse effects on health, or acute eye exposure that would prevent escape from a hazardous atmosphere.”
With reference to odor thresholds it should be noted:
The method of defining and determining odor thresholds varies widely, thereby giving rise to a significant range of reported odor thresholds for many substances. Individuals may also respond differently to the same odor. At a given concentration, one person may smell and recognize the odor, while another person may barely notice it. The odor thresholds reported in the literature are typically determined for a single constituent, with no other chemicals present in the air. The single constituent situation rarely occurs in the workplace. Therefore, caution must be exercised in using these numbers.
Referenced OELs are based upon ACGIH’s TLVs, except where noted in the chart.