An Overview of Occupational Exposure Banding
An important focus of occupational exposure banding (OEB) is to successfully characterize chemical hazards so that appropriate risk management decisions can be made quickly and consistently. This process is vitally important in cases where chemical substances do not yet have established occupational exposure limits (OELs). Here we review occupational exposure banding and look at the process proposed for it by the National Institute for Occupational Safety and Health (NIOSH).
The Toxic Substances Control Act (TSCA) Chemical Substance Inventory contains tens of thousands of commercially available chemicals. Nevertheless, only a small portion of these substances have had OELs developed for them. Without OELs, identifying safe levels of chemical exposure can be extremely difficult. By employing OEB, however, approximations can be determined. OEB is a process designed to assign chemical substances into categories (“bands”) based on their strength and the severity of the detrimental health effects that may result from exposure to them.
Occupational Exposure Banding Process
NIOSH has proposed a process to apply OEB to a significantly greater number of chemicals used in the workplace. The process places chemicals into one of five bands, designated A through E. The assigned bands correspond with a range of exposure levels deemed to be protective for worker health. Band A signifies the highest exposure concentration range, while Band E represents the lowest. Similarly, Bands A and B include chemicals that elicit negative effects at only high levels, while Bands C, D, and E include chemicals that produce adverse effects at low levels.
NIOSH’s proposed process utilizes a three-tiered approach:
- Tier 1
- Aligned with the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), the proposed Tier 1 OEB process utilizes GHS hazard code and category information and determines the corresponding band for each code.
- Tier 2
- The proposed Tier 2 OEB process uses data from a variety of NIOSH-recommended sources and compares that information to NIOSH Tier 2 criteria. While this is a more time-consuming process than that of Tier 1, the data upon which the resulting band is derived are more reliable.
- Tier 3
- Utilizing expert judgement and an analysis of available dose-response data, the proposed Tier 3 OEB process requires an in-depth evaluation of relevant primary literature and associated information.
A key benefit of the OEB process is that it requires less time and effort for chemical categorization than standard OEL development. Because it is dependent on the quantity and the quality of available data, however, this process may not be applicable in all instances.
Accessing Additional Information
For more specific information on occupational exposure banding, and to access the original OEB process proposal document, visit the NIOSH website.