OSHA Revises Hazard Communication Standard

On May 20, 2024, OSHA published a final rule revising the Agency’s Hazard Communication Standard (HCS), which requires that workers be informed of chemical hazards.  The rule aligns the HCS with Revision 7 (Rev. 7) of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), which is updated biennially by the United Nations.

The 318-page final rule includes special labelling provisions for small containers and mandates use of prescribed concentration ranges in safety data sheets (SDSs) when a chemical concentration is claimed as confidential.  The final rule also revises the definitions and classification considerations for various health hazards, adds a new hazard class (desensitized explosives) and three new hazard categories, and makes a number of modifications to the formatting and language that must be used on labels and SDSs.

Though the rule was largely finalized as proposed, OSHA amended one provision in response to industry pushback.  In the proposed rule, OSHA included language requiring that chemical manufacturers and importers evaluate chemical hazards “under normal conditions of use and foreseeable emergencies.”  Many commenters argued that the provision would be overly burdensome, requiring manufacturers to anticipate all possible downstream uses.  In response, OSHA eliminated the language, instead mandating that hazard classifications include “any hazards associated with the chemical’s intrinsic properties,” such as changes to the chemical’s physical form or chemical reaction products associated with reasonably anticipated uses.

The final rule is effective July 19, 2024, and contains staggered compliance deadlines.  Chemical manufacturers, importers, and distributors evaluating substances must update labels and SDSs within 18 months and must make any necessary updates to alternative workplace labelling, hazard communication programs, and trainings within 24 months.  The corresponding compliance dates for mixtures are 36 months and 42 months, respectively.  However, OSHA is not requiring chemicals that have been released for shipment to be relabeled.

GHS Rev. 7 was published in 2017.  Though GHS Rev. 8 was published before OSHA released the proposed rule, OSHA opted to align the HCS with Rev. 7 in large part because major trading partners (including Canada, Europe, and Australia) have adopted or are planning to adopt Rev. 7.  However, OSHA integrated some elements of Rev. 8 that the Agency believes will better protect workers, such as an updated method of classifying skin corrosion/irritation that expands use of non-animal test methods.

The final rule marks the first major update to the HCS since 2012, when the Agency adopted GHS Rev. 3.  A previous Verdant Law blog post on the proposed rule can be found here.

OSHA Proposes Revisions to Hazard Communication Standard

On February 15, 2021, OSHA posted a notice of proposed rulemaking to make changes to the Hazard Communication Standard.  The proposed changes include updates the criteria for classification on health and physical hazard, updating labels, new labeling provisions for small containers, technical amendments for the contents of safety data sheets, and revisions to definitions of certain terms.

The revised criteria for classification of certain health and physical hazards now includes any hazards associated with a change in the chemical’s physical form or from a reaction with other chemicals. The revised provisions for updating labels now includes the date the chemical is released for shipment.  Labels for bulk shipments can be on the immediate container or with the shipping papers, bills of lading or other electronic means that makes it immediately available to workers “in printed form on the receiving end of shipment”.

The proposed changes also state that chemical manufacturers or importers need to update the label for each individual container with each shipment, but do not need to relabel chemicals that have been released for shipment and are awaiting future distribution. For the new labeling provisions for small containers, additional options are available in situations where it is not feasible to use the full label information.  This includes putting the full label information on an outer package, a statement on the outer package that the smaller container needs to remain in the outer package when not in use, and at least has the product identifier on containers less than or equal to 3 ml.

OSHA is taking public comments on all of the proposed changes and the use of electronic template files to create safety data sheets and labels.  The comment period is open until May 19, 2021.

OSHA releases Hazard Communication Standard inspection procedures.

The U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA) has released a new Directive outlining the changes in enforcement caused by the modification of the Hazard Communication Standard (HCS 2012) to harmonize with the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals (GHS). The new Directive, titled Inspection Procedures for the Hazard Communication Standard (HCS 2012), describes how to determine if a violation has occurred under the revised standard as well as how it will be enforced both during its transition period and after full implementation.

The Inspection Procedures note that HCS 2012 is based on GHS Revision 3 (2009), not the more recent Revisions 4 or 5 issued by the UN in 2011 and 2013, respectively. The Directive notes that using a more recent version of GHS may result in noncompliance with HCS 2012 “if it contradicts or casts doubt on OSHA required information.” Notably, OSHA requires that precautionary and hazard statements incorporated from GHS be changed to mandatory, e.g., “should” must be replaced with “shall.”

The Directive provides significant discussion on hazard classification under the revised standard. Classification must be based on criteria specific to each hazard class, and evaluations must “consider all available data on the hazards.” Other considerations include quality and quantity of data and positive and negative results in a single weight-of-evidence determination. Detailed evaluation procedures are included in the Directive’s appendices. In terms of inspection guidelines, the Directive notes that “[t]he adequacy of a company’s hazard classification should be assessed primarily by examining the outcome of that classification.”

The HCS 2012 labeling and SDS requirements went into effect on June 1, 2015 (except for distributors, for whom labeling requirements do not apply until December 1, 2015). However, where a company has “exercised ‘reasonable diligence’ and ‘good faith’ to obtain HCS 2012-compliant SDSs from upstream suppliers but have not received them, they will be allowed limited continued use of HCS 1994-compliant MSDSs and labels.”

Final OSHA Rule Published on Globally Harmonized System of Classification and Labeling of Chemicals


March 26, 2012, the Federal Register published OSHA’s final Globally Harmonized System of Classification and Labeling of Chemicals (GHS).  With this rule OSHA has modified its Hazard Communication Standard (HCS) to be consistent with to the United Nations’ System.

GHS Requirements

OSHA estimates that 880,000 hazardous chemicals are currently used in the U.S., and over 40 million employees are now potentially exposed to hazardous chemicals in over 5 million workplaces.  Approximately 75,000 firms create hazardous chemicals (i.e., products, substances, or mixtures) for which new labels and ‘safety data sheets’ (formerly material safety data sheets) will be required.

OSHA explains that implementation of the GHS will improve HCS by changing the performance requirements for labels to the GHS-specific requirements that labels include four standardized elements: a signal word; hazard statement(s); pictogram(s); and precautionary statement(s).  The appropriate label elements for a chemical are to be determined by the hazard classification.  Standardized label elements will better convey critically important hazard warnings, and provide useful information regarding precautionary measures that will serve to better protect employees than the performance-oriented approach of the current rule.

Chemical manufacturers and importers will be required to re-evaluate chemicals according to the GHS criteria.  Chemicals must be classified based on the type and degree of hazards posed.  For health hazards, this will involve assigning the chemical both to the appropriate hazard category and subcategory (called hazard class).  For physical hazards new criteria are generally consistent with current DOT transportation requirements.  Preparation and distribution of modified labels and safety data sheets by chemical manufacturers and importers will also be required.


The rule adopts only sections of the GHS within the scope of OSHA jurisdiction.  DOT, CPSC and EPA will implement GHS at a later date.  EPA and OSHA have worked together to develop a common position on coverage of pesticides and chemicals.  The GHS will not require additional labels on pesticides labeled under EPA requirements; that is, the final products that enter into commerce.  However, OSHA GHS requirements will apply to the other chemical ingredients of pesticides; the ‘inactive’ ingredients or cleaning products that are hazardous.  This is a continuation of current OSHA HCS worker protection requirements.  OSHA anticipates that EPA will provide guidance to their regulated community on how to develop an OSHA GHS-compliant SDS to avoid conflict with pesticide labeling requirements.

Key GHS Elements

Hazard communication.  A key goal of the final GHS is to better communicate hazard information to those most at risk—the workers exposed to hazardous chemicals Hazard communication requirements are provided in 29 CFR § 1910.1200.  Appendix C, Allocation of Label Elements, details how specified label elements apply to each hazard class and hazard category.  Appendix D, Safety Data Sheets, specifies requirements for the 16 SDS elements.

Concentration limits.  OSHA announced it will require the most protective GHS concentration limits for hazard classifications.  For example, for sensitizers and reproductive toxins, the final rule requires information to be provided on labels and safety data sheets at concentrations above 0.1%.  (See e.g., Appendix C, Allocation of Label Elements.)

Precautionary statements.  In addition to hazard statements, the GHS requires precautionary statements that describe recommended measures that should be taken to protect against hazardous exposures, or improper storage or handling of a chemical.  (See Appendix D, Safety Data Sheets).  Precautionary statements must also address hazard information necessary to protect workers from “hazards not otherwise classified that have been identified during the classification process.” (See Table D.1.)

Mixtures.  Health hazards posed by mixtures should be addressed based on the risks posed by the mixture itself, rather than by the hazards posed by the component chemicals individually.  The GHS does allow alternative classification methodologies where primary data are unavailable, including extrapolation and bridging.  The rule specifies procedures for determining whether mixtures are covered by the Standard.

Chemical manufacturers, importers, distributors, or employers who become newly aware of any significant information regarding the hazards of a chemical shall revise the labels for the chemical within six months of becoming aware of the new information.  New information about hazards and ways to protect against hazards must be added to the SDS within three months.

OSHA has modified General Industry Standards containing hazard classification and communication provisions so that they will be internally consistent and aligned with the GHS modifications to the HCS.


Timeline.  Compliance with all of the provisions for preparation of new labels and safety data sheets is required by June 1, 2015.  Distributors will be allowed an additional six months to distribute containers received from chemical manufacturers and importers with the old labels and MSDSs in order to accommodate those they receive very close to the compliance date.  Workplace labels and training programs must be updated by June 1, 2016.

State implementation.  OSHA intends to closely scrutinize amendments to previously approved State hazard communication standards to ensure equal or greater effectiveness, including assurance that any additional requirements do not conflict with, or adversely affect, the effectiveness of the national application of OSHA’s standard.

Guidance.  OSHA will be offering guidance materials such as quick cards and fact sheets to aid firms in developing and implementing the training requirements of this rule.  OSHA will also be releasing a small business compliance guide to provide additional guidance to small businesses, which will ease the economic impact and compliance burden.

Next Steps

OSHA notes that the GHS is a living document, and the UN actively reviews it and considers possible changes based on implementation experiences and other information.  These changes are made on a two-year cycle, referred to as a biennium.  The OSHA proposal and the final rule are based on Revision 3 of the GHS.  OSHA will undertake future rulemaking as necessary to reflect new technological and scientific developments and UN revisions to GHS requirements.

Although not addressed in the rule, OSHA discusses interest in the development of a common classification database.  The European Union plan to deploy one.  Japan, Taiwan, South Korea, and New Zealand have already done so.  However, classifications in these databases are not necessarily the same for the same chemical.  OSHA would like an international database of classifications developed and maintained.  A UN Sub-committee has been established to explore the issue further.

OSHA to Adopt Final GHS Rule by August 2011

Globally Harmonized System of Classification and Labeling of Chemicals (GHS):

On December 20, 2010, the Occupational Safety and Health Administration (OSHA) released its Fall 2010 Unified Agenda.  75 Fed. Reg. 79604.  The Agenda sets August 2011 as the date for publishing a final rule that will modify the current hazard communication standard (HCS) at 29 CFR 1910.1200 to incorporate elements of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS).  Readers will recall that GHS is a system the United Nations (UN) developed for standardizing and harmonizing the classification and labeling of chemicals to help ensure their safe use, transport and disposal.  Publication of the final rule is the culmination of a five-year process that has left the United States behind many countries in its implementation of GHS.

The UN first published the GHS in 2003 in response to the diverse and sometimes inconsistent hazard classification and communication systems in use around the world.  Governments, industry, and labor, working through the UN, hoped that a harmonized system would increase safety and reduce the regulatory burden associated with the global trade in chemicals.  Under the GHS, labels would include signal words, pictograms, and hazard and precautionary statements and safety data sheets would have a standardized format.

When the GHS system was first adopted, the goal was implementation in each country by 2008.  However, that has not happened.  Some countries met the deadline while others did not.  Japan required compliance in 2006, and New Zealand and Korea required at least partial compliance in 2008.   The European Union’s GHS regulation entered into force in January 2009.   (Information on other countries’ adoption is available here.)

Adoption in the US has been slower, possibly because several agencies are involved, including the Environmental Protection Agency (EPA), the Consumer Product Safety Commission (CPSC), and the Department of Transportation (DOT).  Each agency is evaluating its existing regulations and guidance, and making the necessary changes.  OSHA’s adoption of GHS has been particularly slow.  The Agency first published an advanced notice of proposed rulemaking in September 2006, 71 Fed. Reg. 53617, and then waited almost three years before proposing a rule, 74 FR 50279, and finally initiated several public hearings thereafter.   Some question whether US industry, particularly smaller businesses, have been hurt by the delay since smaller companies sometimes cannot afford to comply with multiple countries’ hazard communication systems and therefore avoid significant international trade.

Multiple aspects of OSHA’s current HCS will be affected by the impending rule.  According to OSHA’s website, the following major areas are subject to significant changes.

  • Hazard classification: Specific criteria for classification of health and physical hazards, as well as classification of mixtures will be adopted.
  • Labels: Chemical manufacturers and importers will be required to provide a label that includes a harmonized signal word, pictogram, and hazard statement for each hazard class and category. Precautionary statements must also be provided.
  • Safety Data Sheets: A prescribed 16-section format will be required for all safety data sheets.
  • Information and training: The GHS does not address training. However, the proposed rule will require workers to be trained on GHS within two years of the publication of the final rule to facilitate recognition and understanding of the new labels and safety data sheets.

Additional details about the proposed changes are available in the Federal Register notices cited above.  For those interested in learning more, OSHA has published a lengthy comparison of the GHS and HCS, and a comprehensive discussion of the GHS also is avaialble on OSHA’s website.