US Dept of Labor

Occupational Safety & Health AdministrationWe Can Help

Standard Interpretations - Table of Contents
• Standard Number: 1910.1200

March 4, 2014

Erik C. Baptist
American Petroleum Institute
1220 L Street, NW
Washington, DC 20005

Re:   Request for Interpretation of OSHA's Amended Hazard Communication Standard (HCS 2012) about Hazards Not Otherwise Classified

Dear Mr. Baptist:

This letter is being issued to API to provide additional guidance on how to apply the requirements for Hazards Not Otherwise Classified (HNOC) under the March 26, 2012, revisions to OSHA's Hazard Communication Standard (HCS 2012).

Under OSHA's Hazard Communication Standard, an HNOC is defined as follows:

an adverse physical or health effect identified through evaluation of scientific evidence during the classification process that does not meet the specified criteria for the physical and health hazard classes addressed in this section. This does not extend coverage to adverse physical and health effects for which there is a hazard class addressed in this section, but the effect either falls below the cut-off value/concentration limit of the hazard class or is under a GHS hazard category that has not been adopted by OSHA (e.g., acute toxicity Category 5).

29 C.F.R. 1910.1200(c).

Classifiers may rely on the following guidance in applying the definition of an HNOC under HCS 2012:

  1. An adverse physical or health effect is a material impairment of health or functional capacity, as that phrase is used in section 6(b)(5) of the OSH Act, 29 U.S.C. 655(b)(5), resulting from workplace exposure to a chemical.

  2. A health effect is determined in accordance with the weight of evidence criteria in A.0.3.

  3. The term physical effect generally refers to a material impairment of health or functional capacity caused by the intrinsic hazard(s) of a particular chemical in normal conditions of use or foreseeable emergencies. Scalds caused by exposure to chemicals at high temperatures, and slips and falls caused by treading on a solid chemical shaped in a rounded form or spilled liquids are not covered physical effects under the HNOC definition. By way of example, water is not classified as an HNOC merely because an employee might be scalded by contact with boiling water or because an employee might contract hypothermia by being immersed in cold water for a long period of time. Similarly, water is not classified as an HNOC by virtue of the fact that an employee might be injured when slipping and falling on a wet surface or when sprayed by water at high pressure. The foregoing examples of adverse physical effects that are outside the scope of HNOCs are designed to assist in better understanding the concept of HNOCs. They are not intended to be exhaustive or limited to chemicals, such as water, which are not hazardous chemicals.

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA requirements are set by statute, standards, and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules.


David Michaels, Ph.D, MPH

cc: Lawrence P. Halprin, Esq.
Keller and Heckman LLP
Attorney for API

Standard Interpretations - Table of Contents

Thank You for Visiting Our Website

You are exiting the Department of Labor's Web server.

The Department of Labor does not endorse, takes no responsibility for, and exercises no control over the linked organization or its views, or contents, nor does it vouch for the accuracy or accessibility of the information contained on the destination server. The Department of Labor also cannot authorize the use of copyrighted materials contained in linked Web sites. Users must request such authorization from the sponsor of the linked Web site. Thank you for visiting our site. Please click the button below to continue.