As part of the Occupational Safety and Health Administration’s efforts to protect workers from the hazards of chemicals, the agency plans to issue new guidance on how to apply the Weight of Evidence approach when dealing with complex scientific studies. On February 16, OSHA will begin accepting comments on its Guidance on Data Evaluation for Weight of Evidence Determination, which is intended to help employers consider all available information when classifying hazardous chemicals.

The “weight of evidence” approach assists manufacturers, importers and employers to evaluate scientific studies on the potential health hazards of a chemical and determine what information must be disclosed on the label and safety data sheet (SDS) for compliance with the Hazard Communication Standard. This draft is a companion document to a recently posted Hazard Classification Guidance.

“It is vitally important that workers and employers be given complete and accurate information about the hazards associated with exposure to the chemicals with which they work. Without that, how can they ensure they are protected,” said Assistant Secretary of Labor for Occupational Safety and Health Dr. David Michaels. “This guidance will help educate chemical manufacturers and importers about OSHA’s expectations on how to prepare accurate safety data sheets and labels required to protect worker safety and health.”

Under the Hazard Communication Standard, chemical manufacturers and importers must review all available scientific evidence concerning the physical and health hazards of the chemicals they produce or import to determine if they are hazardous. This document helps the label and SDS preparer apply the Weight of Evidence approach when dealing with complex scientific studies.

This guidance document is not a standard or regulation and it does not create any new legal obligations and is intended to assist employers in providing a safe and healthful workplace. The recommendations are advisory in nature, informational in content, and intended to educate scientists and non-scientists alike who prepare labels and SDSs so that they provide accurate and consistent information.