On February 16th, 2021, the United States Government Occupational Safety and Health Administration (OSHA) published a notice of proposed rulemaking (NPRM) to revise the Hazard Communication Standard (HCS) to align with Revision 7 of the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals (GHS). The revision has three main goals: 1) to maintain alignment with GHS and the current state of science and knowledge; 2) to help align the regulations with international trading partners and other US agencies like Department of Transportation; and 3) to address issues identified by stakeholders with the 2012 implementation of the HCS which follows Revision 3 of GHS.

To accomplish these goals, the NPRM outlines some administrative changes such as revised definitions and terms used for better clarification of hazards and their criteria, and proposes the following changes to the classification and labelling of chemicals:

  1. Revision of the classification criteria for certain health and physical hazards.

The revised HCS will include a new hazard class for desensitized explosives, will include unstable gases and pyrophoric gases in the flammable gas class, and will introduce a non-flammable aerosol category in the aerosols class.

  1. New labelling provisions for small containers and revised provisions for updating labels.

One of the issues identified with the current HCS was the labelling requirements for small containers, which often do not have enough space to include all the required labelling information, have compromised readability if all the information is condensed to fit onto the small label, or the use of a fold-out label is not feasible with the size or shape of the container. OSHA therefore proposes that—if it is not feasible to use a pull-out label, fold-back label, or tag for a product—labels for containers with a capacity of ≤100 mL need only display the product identifier, pictograms, signal word, manufacturer’s name and phone number, and a statement that the complete label information is provided on the immediate outer package. For containers ≤3 mL where a label would interfere with the normal use of the container, only the product identifier needs to appear on the container. However, OSHA makes these provisions on the condition that these small containers must be stored in outer packaging with the complete label information when not in use.

With respect to updating labels, the proposed revisions will add a provision for products with long distribution cycles in which chemicals that have already been released for shipment need not be re-labelled when new information is required or becomes available, but rather an updated label must be provided with each container in each shipment.

  1. Amendments to the required content of safety data sheets.

In section 2, OSHA proposes to reorganize the presentation of the information to emphasize the hazards that are present during the normal use of the product when those hazards result from a chemical reaction. The language in the standard precautionary statements will also be updated to align with Revision 7.

In section 3, OSHA proposes two new provisions for the concentrations or concentration ranges to be claimed as trade secret. The first provision would allow manufacturers/ importers/employers to withhold chemical concentrations as trade secret, which is not permitted under the current HCS. Second, where the actual concentration or concentration range is claimed as trade secret, OSHA is proposing to use the same prescribed ranges as required by Canada and is considering options to either mandate this requirement or make this a non-mandatory option for which OSHA will provide guidance. OSHA is also considering an option to allow manufacturers to use their own range provided that it is narrower than any prescribed range. OSHA is also seeking public comment regarding the disclosure of chemicals with physical hazards in section 3.

In section 9, OSHA proposes to include particle characteristics for solid products.

  1. Additional clarification for shipments that are also regulated by DOT

The revised HCS will update the requirements for bulk shipments, in which labels may be placed on the immediate container or transported with shipping papers or other documentation—whether physically or electronically—so that they are readily available to workers on the receiving end. The revisions will also allow GHS hazard pictograms to appear on the shipping label.


OSHA is also seeking public comment on including some considerations from Revision 8 into the revised HCS, including:

  • Non-animal test methods for skin corrosion/irritation;
  • Displaying classification criteria for aerosols in table format rather than a decision logic, and;
  • Medical response precautionary statements.


You can read the proposed rulemaking and submit your comments here. Comments must be submitted by April 19, 2021.


To discuss how these changes may affect your product SDSs and workplace labels, contact us!