OSHA calls for comments on significant proposed amendments to align Hazard Communication Standard with the United Nations Globally Harmonized System of Classification and Labelling of Chemicals.

The US Department of Labor’s Occupational Safety and Health Administration (OSHA or the agency) published a proposed rule to amend its Hazard Communication Standard (HCS), 29 C.F.R. § 1910.1200. The February 16, 2021 amendments would align the HCS with the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals (GHS) 2017 Seventh Revision (GHS Revision 7) in various respects, including by modifying the requirements to classify hazards and to communicate those hazards and other information in Safety Data Sheets (SDS) and labeling. The public comment period on the proposed rule runs until April 19, 2021. The OSHA webpage for the proposed rule provides a red-line strikeout comparison between the current HCS and the proposed amendments, which will be helpful for stakeholders to review as they prepare comments.

If finalized, the proposed rule would have significant implications for US manufacturers, importers, and distributors of “hazardous” substances. In particular, the amendments to the hazard classification criteria would require such parties to develop and issue new SDSs and labels for many substances, especially for aerosols, flammable gases, and desensitized explosives. On the other hand, the amendments would help to ease burdens associated with inconsistencies between the current HCS and requirements in other jurisdictions. In addition to harmonizing the HCS with the GHS Revision 7, the amendments would also align the HCS with standards used by many US trading partners, including Canada, the European Union, New Zealand, and Australia. Notably, OSHA acknowledges that its proposed rule does not account for the latest version of the GHS — i.e., in 2019, the GHS was updated to its Eighth Revision (GHS Revision 8) — but solicits comments on approaches for further harmonization.

The discussion below highlights key amendments to the current HCS in OSHA’s proposed rule and outlines the potential implications for manufacturers, importers, and distributors of chemicals in the US.

Proposed Revisions to Safety Data Sheets and Labels

Labels for Bulk Shipments. OSHA proposes increased flexibility in label requirements for the transport of bulk shipments of hazardous chemicals (e.g., in tanker trucks or rail cars), to align with a 2016 policy OSHA created jointly with the Department of Transportation (DOT) Pipeline Hazardous Materials Safety Administration, which regulates the interstate shipment of hazardous materials. The proposed rule would permit labels to be placed on the container, or alternatively, to be transmitted via other means (such as shipping papers or electronically) so label information would be available immediately to workers receiving the shipment. Moreover, if a DOT pictogram appears on a label, the HCS pictogram for the same hazard would no longer be required. Ultimately, these amendments, if finalized, would allow use of the same labels for shipping containers as for containers in the workplace.

Relabeling/Release for Shipment. Under the current HCS, labels must be revised within six months after new hazard information is discovered. The end of this six-month period may even come before a labeled container has been shipped, especially for products with long distribution cycles. The proposed rule would offer companies more flexibility by not requiring relabeling of any container that has already been “released for shipment” by the manufacturer or importer — meaning that the container is the final packaging in which the chemical will be shipped and is awaiting distribution (e.g., a container stored at a warehouse or distribution center awaiting shipping). Rather than require the physical relabeling of the container, the manufacturer or importer must “provide the updated label” for the container with the shipment of the container. OSHA does not explain further what “providing” the label entails, but it might include providing an updated label electronically or with the shipment papers. OSHA specifically requests comments on whether these proposed changes are adequate to address issues with relabeling, including potential safety concerns for workers receiving shipments that have not been relabeled.

Labels for Small Containers. Currently, labels on shipped containers must reflect all hazards, in addition to pictograms and precautionary statements. For small containers, however, including all required information may render the text too small to read and alternatives are not always feasible. In the past, OSHA used Letters of Interpretation to allow parties to provide more limited information on the small container label upon a showing of infeasibility, while requiring full information on the outside packaging. Now, OSHA is proposing to codify its existing interpretations. In particular, the proposed rule would limit requirements for the labeling of containers smaller than 100 ml, and eliminate labels for very small containers (under 3 ml), if a complete label is not feasible.

Concentration Ranges on SDS Claimed as Trade Secrets. One major proposed amendment would permit the concentration ranges of ingredients to be claimed as a trade secret on the SDS. Instead of the actual range, the SDS could provide the ingredient’s concentration as a range selected from a list of preset ranges. The proposed list is aligned with similar Canadian requirements. OSHA is interested in receiving public comments on a number of specific questions related to these concentration ranges, such as whether they are too wide, whether they adequately inform downstream workers and users of hazards, and whether ranges can be combined.

Contents of Safety Data Sheets and Labels. The proposed rule would modify hazard classification requirements, the details and implications of which will be discussed in the next section. Separately, however, OSHA also is proposing amendments to the content requirements for SDSs and labels to align with GHS Revision 7 in the following areas:

  • Identification of hazards associated with a change in physical form
  • Identification of hazards that can occur under normal conditions of use as a result of a chemical reaction
  • Changes to physical and chemical information requirements, including requiring information on particle size and characteristics
  • Identification of hazards on interactions with other chemicals
  • A description of how toxicological information was derived (e.g., from modeling such as SAR/QSAR, or read-across)
  • Changes to various hazard and precautionary statements

Notably, the current HCS would not prohibit the inclusion of the above GHS Revision 7 content, but does not require it. Some manufacturers and importers have SDSs and labels for hazardous substances distributed in the US that already align with this GHS Revision 7 content as part of their effort to harmonize content globally as much as possible. For all others, however, the proposed rule would necessitate development of new SDSs and labels, even for substances for which the hazard classification would not change under the proposed rule.

Proposed Revisions and Additions to Hazard Classes and Categories

The proposed rule involves a number of amendments to hazard classes, and also would adopt new physical hazard classes and hazard categories to align with GHS Revision 7. If finalized, a manufacturer or importer of any impacted substance would be required to revisit its classification and adjust the SDS and label accordingly.

Flammable Gases. The proposed rule would modify the Flammable Gases hazard class. Most significantly, the proposal subdivides Category 1, which covers a wide variety of flammable gases, into subcategories 1A (extremely flammable gas) and 1B (flammable gas). Under the proposal, all flammable gases that are currently classified as Category 1 would be classified as Category 1A, unless data show that the gas is less hazardous (e.g., lower flammability limit), which would qualify it for Category 1B. Beyond the subcategorization of Category 1, the proposed rule would add further sub-subcategories to the new Category 1A, dividing that Category into flammable, pyrophoric, and chemically unstable gases.

Desensitized Explosives. The proposed rule would add a new physical hazard class for desensitized explosives — i.e., chemicals treated with liquid (e.g., wetted, diluted, or dissolved) to stabilize the chemical and reduce its explosive properties. Desensitized explosives are classified as explosives under the current HCS, but fall within their own hazard category under GHS Revision 7. These types of explosives can pose a specific hazard in the workplace when the stabilizer is removed, which OSHA believes should be identified and communicated to workers. The proposed desensitized explosives hazard class would be added to the HCS as Appendix B.17, with various subcategories and differentiated hazard warnings.

Aerosols. The proposed rule would expand the existing aerosol hazard class to include a new “Category 3”. As a result, non-flammable aerosols, which previously were not classified or were placed in another class, would fall within this Category 3 and would no longer be classified as gases under pressure. Flammable aerosols would be classified in Categories 1 or 2, depending on their flammability.

Further Issues Open for Public Comment

OSHA is also requesting comment on a number of discrete issues relevant to stakeholders.

Alignment with GHS Revision 8 – Non-Animal Testing Data. While the proposed rule is primarily intended to align the HCS with the GHS Revision 7, OSHA is also proposing several minor changes taken from GHS Revision 8, such as adopting specific wording in the aerosol classification table. Most significantly, the proposed rule would add provisions that expand the use of non-animal test data for hazard classification of the skin irritation/corrosion hazard class. OSHA recognizes that significant recent advancements in non-animal testing methods, such as in vitro and in silico techniques, have occurred, and the agency wishes to encourage the use of such testing strategies to develop hazard information. Adopting these updates in the HCS would not require a re-evaluation of chemicals already classified.

Electronic Technology on Labels. OSHA requests comment on the implications of allowing the use of “newer electronic technology,” such as quick response (QR) codes or radio-frequency identification (RFID), on chemical packaging labels. As OSHA notes, these technologies can electronically store large amounts of information that otherwise would not fit on standard labels, and therefore, could significantly expand the information associated with a chemical packaging label.

OSHA Guidance Documents. OSHA is requesting comments on the type of guidance that the public “may find useful” in understanding the HCS amendments in the proposed rule, such as formal guidance documents, Letters of Interpretation, or enforcement directives.

Timeline for Future HCS Updates. OSHA notes that since aligning the HCS with the GHS Revision 3 in 2012, the agency has intended for the HCS to track the more recent revisions of the GHS as they are issued. However, OSHA has not provided a specific timetable to periodically harmonize the HCS with the GHS, and is requesting comment on whether the agency should adopt a formal periodic schedule for HCS harmonization updates.