OSHA extends comment period for draft ‘weight of evidence’ guidance

Washington – OSHA has extended, to May 2, the deadline to submit comments on the agency’s draft document on using the “weight of evidence” approach to classifying hazardous chemicals.

The new deadline is in response to stakeholder requests for more time to review the document and provide constructive responses, OSHA stated. The original deadline was March 31.

The weight of evidence process is intended to help employers evaluate scientific studies on chemical hazards. These evaluations can then be used to determine what information needs to be included on chemical labels and Safety Data Sheets as required under the Hazard Communication Standard.

The draft provides guidance on how employers can use the weight-of-evidence approach in a manner that is consistent with criteria in the United Nations’ Globally Harmonized System of Classification and Labeling of Chemicals, which served as the basis for OSHA’s recent update to its hazcom rule. The document outlines for employers what information needs to be considered when classifying health hazards, how to evaluate the evidence in classification, the scope of weight of evidence and considerations when using weight of evidence.