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Reviewing the Major HazCom Changes


Changes to Hazardous Chemical Classifications 

Recap of the NPRM

The NPRM proposed several changes to how certain chemicals are classified to align with the classification criteria of those chemicals in GHS Revision 7.

Aerosols & Chemicals Under Pressure 

OSHA proposed to follow GHS Rev. 7 (UN GHS, 2017, Document ID 0060) by expanding the existing Flammable Aerosols hazard class (appendix B.3) to include non-flammable aerosols, as well as flammable aerosols. Non-flammable aerosols would now be classified as a hazardous chemical under Category 3, while flammable aerosols will continue to be under Category 1 or Category 2.

Under GHS Rev. 3 and the current HazCom Standard, Chapter 2.3 and appendix B.3, respectively, were titled “Flammable Aerosols.” Under GHS Rev. 3, the hazards characteristic to non-flammable aerosols were either not classified at all, or more likely, were classified in another health hazard class or physical hazard class (e.g., gases under pressure) (UN GHS, 2009, Document ID 0085). Some products were likely to have been classified as both flammable aerosols and gases under pressure, however this is explicitly forbidden in the new rule..

Osha’s Updated Hazard Communication Elements For Flammable Gases

The change in classification is occurring because classification under HazCom 2012 was based largely on information from the transportation sector, which meant that most aerosols were classified as gases under pressure. Since that time, OSHA has come to the realization that the current classification does not adequately represent the full spectrum of varying aerosol hazards, because aerosol containers have different characteristics including failure mechanisms. Under the proposal, flammable aerosols would be classified in existing Categories 1 and 2 and bear the flame pictogram, while non-flammable aerosols would be in a new Category 3 and have no pictogram.

Classification Criteria For Aerosols

OSHA reports that most aerosols are also classified as gases under pressure by GHS Rev. 3 (and accordingly under the existing HazCom Standard) because of the design criteria of the aerosols (ERG, 2015, Document ID 0163) under DOT regulations. However, since the new rule will explicitly forbid an aerosol to also be classified as a gas under pressure, aerosol manufacturers can expect the proposed classification changes — if pushed through to the final rule — to have a significant impact on the authoring of SDSs for affected products.

In the Federal Register notice for the NPRM, OSHA also solicited feedback from stakeholders on whether to adopt the Chemicals Under Pressure information from GHS Revision 8.

What is a Chemical Under Pressure (CUP)? CUPs are  liquids or solids (e.g., pastes or powders), pressurized with a gas at a pressure of 200 kPa (gauge) or more at 20 °C in pressure receptacles other than aerosol dispensers and which are not classified as gases under pressure. NOTE: CUPS typically contain 50% or more by mass of liquids or solids, whereas mixtures containing more than 50% gases are typically considered as gases under pressure.

What are the criteria for a CUP? Before being considered for classification, your mixture must:

  1. Contain liquid(s) or solid(s) and gas(es);
  2. Must be contained in a pressure receptacle that is not an aerosol container, and cannot also be considered a GUP; and
  3. Pressure must be higher than 200 kPa at 20°C.

* Flammable components include Flammable gases, liquids, and solids. Flammable components do not include pyrophoric, self-heating, or water reactive.

* CUP cannot also be classified as: Aerosols, Flammable Gas, GUP, Flammable Liquid, Flammable Solid.

Finally, OSHA also used the Federal Register notice for the NPRM to solicit stakeholders feedback on whether to adopt a classification procedure based on text in Table XIV in GHS Revision 8. For reference, an image of Table XIV is included below.

Label Elements:

Ghs Label Elements

Desensitized Explosives 

OSHA proposed to align with GHS Rev. 7 (UN GHS, 2017, Document ID 0060) by adding a new physical hazard class for desensitized explosives. There will be 4 categories (1,2,3, and 4) within this new hazard class. 

Table B.17.1 Criteria For Desensitized Explosives

Desensitized explosives are chemicals that are treated in such a way as to stabilize the chemical or reduce or suppress their explosive properties. These types of chemicals can pose a hazard in the workplace if the stabilizer is removed, either as part of the normal work process or during storage of the chemical. Therefore, it is urgent that the hazards be identified and appropriately communicated. 

These chemicals are currently classified as explosives in HazCom 2012, with precautionary statements (e.g. “keep wetted”) used to address additional concerns about measures necessary to keep the chemical stabilized. OSHA concurs with UN GHS Rev 7 that a separate hazard class is warranted to ensure that specific hazards are communicated. The table below shows OSHA’s hazard classes for desensitized explosives. 

Osha’s Hazard Classes For Desensitized Explosives

OSHA states that even though “desensitized explosives” is a new hazard class, the explosion hazards are well-known, and should already be included in current hazard training. 

For example, hazard training should cover that if water, or another wetting solution used to desensitize an explosive happens to dry out, an explosion could occur. Of course, OSHA doesn’t believe that hazard training alone is sufficient, and it maintains that the new classification will further improve workplace safety. 

Flammable Gases

OSHA proposed to subdivide Category 1 of the Flammable Gases hazard class into two subcategories (1A and 1B), and to specify that pyrophoric gases and chemically unstable gases are to be classified as Category 1A. These proposed changes would provide more detailed information about flammable gas hazards, and they correspond to changes made in GHS Rev. 7 (UN GHS, 2017, Document ID 0060). 

Criteria For Flammable Gases

OSHA states in the NPRM that under HazCom 2012, almost all flammable gases are classified as Category 1, so there are no distinctions drawn between gases with wide range of flammable properties. The proposed changes would give downstream users a better understanding of the severity of the hazards associated with flammable gases. Specifically, downstream users could use this information to take appropriate precautions under all conditions (i.e. transport, handling and use) or determine if an available substitute chemical is less hazardous. 

The table below shows OSHA’s updated hazard communication elements for flammable gases. 

Osha’s Updated Hazard Communication Elements For Flammable Gases

Key Industries Affected

Starting on page 49 of the proposed rule, there is a table showing some of the major industries (in terms of numbers of facilities and numbers of employees) that are affected by the proposed changes. 

These include: 

  • Chemical Manufacturing (and all subsectors);
  • Oil and Gas Extraction;
  • Petroleum & Coal Products Manufacturing;
  • Plastics and Rubber Products Manufacturing
  • Merchant Wholesalers (both durable and non-durable goods)
  • Non-Metallic Mineral Product Manufacturing

In the NPRM, OSHA states that their list comes from its search of the North American Industry Classification System (NAICS) for industries that manufacture products impacted by its proposed changes to hazard classifications. 

Changes in the Final Rule


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Changes to Bulk Shipment Labeling Requirements

Recap of the NPRM

In the HazCom NPRM, OSHA proposed to add new paragraph (f)(5)(ii) to address the transport of bulk shipments of hazardous chemicals (i.e. tanker trucks, rail cars, or intermodal containers). The paragraph specifies that labels for bulk shipments of hazardous chemicals may either be on the immediate container, or may be transmitted with shipping papers, bills of lading or other technological or electronic means so that the information is immediately available in print to workers receiving the shipment. 

The paragraph would also codify a policy first introduced by OSHA and the Pipeline Hazardous Materials Safety Administration (PHMSA) in 2016 that clarified procedures for proper labeling of bulk chemicals in transport (PHMSA, 2016, Document ID 0244), and promotes better alignment with DOT regulations. 


The OSHA NPRM also proposed a new definition of “bulk shipment” as “any hazardous chemical transported where the mode of transportation (vehicle) comprises the immediate container (e.g., contained in tanker truck, rail car, or intermodal container).” 

During the September 2021 public hearing, several commenters pointed out that this definition is at odds with the definition of a similar term, “bulk package,” defined by the US Department of Transportation (DOT) as packaging (other than a vessel or a barge) including a transport vehicle or freight container in which hazardous materials are loaded with no intermediate form of containment. That part of the definition is congruent with OSHA’s definition of “bulk shipment,” but the DOT definition also covers large packaging in which hazardous materials are loaded with an intermediate form of containment, such as one or more articles or inner packaging. 

Some of the stakeholders at the 9/21 public hearing pointed out that while OSHA has stated their intent to “better harmonize the HCS with DOT regulations,” the differences in definition have the potential to cause confusion. Several suggested that OSHA simply incorporate the DOT definition by reference, which would not only address the discrepancy but also ensure that the alignment continues whenever DOT may update its definition in the future. 

Changes in the Final Rule


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Guide to HazCom Revisions Chemical Classifications Based on “Normal Conditions of Use”

Recap of the NPRM 

The NPRM proposed changes to paragraph (d)(1) to state that for each chemical, the chemical manufacturer or importer shall determine the hazard classes and, where appropriate, the category of each class that applies when the chemical is being classified under normal conditions of use and foreseeable emergencies.  

OSHA stated in an April 13, 2021 webinar organized by Society for Chemical Hazard Communication (SCHC) that they view this addition as reiterating OSHA’s position, given in paragraph 1910.1200 (b)(2) of the HazCom Standard and clarified in letters of interpretation dating back to 2004, that hazard classification must cover the normal conditions of use and foreseeable emergencies. Additionally, OSHA stated that these identified hazards would need to appear on the shipped container labels. 

When a caller during the SCHC call asked for clarification on this point, OSHA cited the example of combustible dust that may be generated during use of a product. The OSHA representative stated that if regular use of a product resulted in combustible dust, the manufacturer would need to account for that hazard to indicate it on the shipped container label. 

On a related but somewhat different issue, OSHA proposed changes to Section 2 of the SDS to require that hazards identified under normal conditions of use resulting from a chemical reaction must appear on the SDS, even though these hazards do not need to be listed on the shipped container label. 

This proposed change represents stricter classification requirements than those that currently exist under HazCom. The proposed text clearly states that a chemical must be classified according to normal conditions of use and foreseeable emergencies, as well as hazards associated with a change in physical form or resulting from a reaction with other chemicals under normal conditions of use. According to the proposed rule, “known intermediates, by-products and decomposition products that are produced during normal conditions of use or in foreseeable emergencies must be addressed in the hazard classification.” As such, this will create new classification challenges for certain industry sectors, such as metal and alloy manufacturing where products regularly undergo chemical reactions under normal conditions of use. 

Commenters at the public hearing held on September 21–23, 2021 raised a number of objections to these requirements, especially the proposed obligation to consider potential downstream reactions and changes in physical state. The feedback provided by these commenters can be grouped into three primary arguments: 

1) Chemical manufacturers are too far “upstream” in the supply chain to know all the possible uses of their chemical products, or all the associated physical conditions and other chemicals that they may encounter. Trying to obtain that information across all the different users and uses of a single product would be extremely difficult, if not impossible. 

2) Even if manufacturers theoretically could get that information regarding all downstream uses, many of its end users may have proprietary processes that prevent or complicate the sharing of that information. 

3) If chemical manufacturers managed to overcome both of the previous obstacles, they’d still have the daunting task of compiling a potentially huge volume of information for inclusion in Section 2 of the product SDS. The presence of all these details could significantly compromise the effectiveness of the SDS and defeat its intended purpose as a source of information about chemical hazards for downstream users. For one, it may confuse users by including details about theoretical reactions and form changes that don’t apply to their own uses of the chemical, and second, it may make the SDS document so long as to be virtually unusable. 

Changes in the Final Rule


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Updated Requirements for SDS Section 9

Recap of the NPRM 

OSHA’s NPRM proposed several updates to SDS Section 9, Physical and chemical properties. OSHA proposed to align Section 9 with the GHS Rev. 7 by listing the required physical and chemical properties of the chemical in the same order that appears in that edition of the GHS (UN GHS, 2017, Document ID 0060), and removing some previous physical properties (e.g. Appearance and Evaporation Rate) and replacing with more appropriate listings from Revision 7. To be clear, OSHA would not actually require the preparers of an SDS to list the physical and chemical properties in a particular order, but OSHA themselves would list them in the same order they’re in within GHS Rev. 7 to simplify preparation for chemical manufacturers that may prepare SDSs for global distribution. For reference, the elements of Section 9 according to GHS Rev. 7 are listed in the table below. 

Elements Of Section 9 According To Ghs Rev. 7

Other proposed changes to section 9 include:  

  • Replacing “appearance” with “physical state” and “color”;  
  • Eliminating “odor threshold” and “evaporation rate” as separate required properties;  
  • Adding the term “kinematic” to the property “viscosity” to better define the appropriate parameter to be characterized (i.e., kinematic as opposed to dynamic viscosity); and  
  • Adding “particle characteristics” as a new physical property.  

That final change will likely be the most significant in terms of additional workload for chemical manufacturers and SDS preparers, so let’s discuss it a little further. 

The new “particle characteristics” category would apply to solids only and the description would include the particle size (median and range) and, if available and appropriate, further properties such as size distribution (range), shape and aspect ratio, and specific surface area.  

Why is OSHA requiring this new category? OSHA maintains that particle characteristics can be an important indicator of the potential for a solid particle to pose health hazards, because particles that are less than 100 microns in size increase the likelihood of exposure, especially through the route of inhalation, and tend to get deeper into the lungs or even into the bloodstream, where they can cause more significant and chronic health issues. 

One of the specific reasons OSHA cited for including the new physical property of particle characteristics related to the real-world example growing use of nanomaterials, which can create potential for exposure to fine particulate matter. As one example, nanosilver is frequently used as a component of appliances such as washing machines and microwave ovens and inside manufactured food storage containers due to its antimicrobial properties. As nanosilver and other nanomaterials come into wider use, the potential for health effects from aggregate exposures increases. 

Inclusion of this information on SDSs would therefore help employers and their workers to understand and avoid the hazards of chemical products consisting of small particles. The particle size information would also facilitate OSHA’s use of aggregate exposures and cumulative risk models for use in setting occupational exposure limits and assessing impacts on worker health.

Changes in the Final Rule


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Labeling Provisions for “Small” and “Very Small Containers”

Recap of the NPRM 

OSHA had received a great deal of feedback and questions from stakeholders since the publication of the 2012 HazCom final rule on the challenges of implementing shipped container label requirements for small containers. 

Proposed changes in the NPRM are intended to address those implementation challenges. Proposed paragraph (f)(12), which addresses labeling of small containers, would specify that chemical manufacturers, importers and distributors would be granted allowances to include less information on the shipped label when they can demonstrate that it is not feasible to use pull-out labels, fold-back labels or tags to provide the full label information as required by paragraph (f)(1).

As proposed in paragraph (f)(12)(ii) of the NPRM, containers with a volume capacity of 100 ml or less may include an abbreviated label specifying the product identifier, pictogram(s), signal word, chemical manufacturer’s name and phone number, and a statement that the full label information is provided on the immediate outer package. 

This revision would codify guidance for small container shipped labels that OSHA had previously published in a 2013 letter of interpretation (LOI). 

Paragraph (f)(12)(iii) further proposes that manufacturers, importers and distributors may include only the product identifier on containers with a volume of 3 ml or less (referred to as “very small containers” in the NPRM) if they can demonstrate that a full label would interfere with the normal use of the container. If the product identifier is printed directly onto the container, no label is required. Stakeholder concerns over requirements and guidance for small labels had long been a question at OSHA & UN SCEGHS meetings. The NPRM proposes a new allowance not provided in any previous OSHA guidance, and accounts for stakeholder feedback on the difficulty posed when labels on very small containers interfere with the normal use of those containers. 

However, there’s an important caveat that applies to both “small” and “very small” containers. The NPRM states that manufacturers, importers and distributors who take advantage of either of the label allowances discussed above must provide the full label information required in paragraph (f)(1) for each chemical on the outer packaging containing the small immediate containers of the chemicals. The small containers, when not in use, must be stored in the immediate outer package, paragraph (f)(12)(iv)(B) of the NPRM proposes that manufacturers must include a statement on the outer packaging stating that the small container(s) must be stored in the outer package bearing the complete label when not in use. 

OSHA’s Preliminary Economic Analysis (PEA) on the impact of the label changes, included in Section VII of the Federal Register notice, states that the allowance for small containers will result in little or no economic benefit, since they believe that affected manufacturers already were aware by now of the allowance given by the 2013 LOI, which would only be codified, not added to, by the NPRM. It’s a different story for the “very small containers” of 3 ml capacity or less. Because OSHA had not previously provided additional allowances for these containers, the proposal within the NPRM would result in significant cost savings for affected chemical manufacturers. Based on OSHA’s PEA, it maintains the affected manufacturers would be concentrated in a few industry sectors like “Other Basic Chemical Manufacturing, Inorganic and Organic” (NAICS 325180 and 325199, respectively) and Pharmaceutical and Medical Manufacturing (NAICS 3254—encompassing 6-digit NAICS 325411, 325412, 325413, and 325414). 

Changes in the Final Rule


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Labeling Provisions for Chemicals “Released for Shipment”

Recap of the NPRM 

OSHA proposed to update paragraph (f)(11) to provide that chemicals that have been released for shipment and are awaiting future distribution need not be re-labeled to incorporate new significant information about hazards. 

However, the chemical manufacturer or importer would still have to provide the updated label for each individual container with each shipment. The purpose of this proposed requirement is to account for the long distribution cycles of some products and the potential hazards workers could face in re-labeling the immediate containers of hazardous chemicals (e.g., chemical exposures, ergonomic issues). 

OSHA simultaneously proposed to add a requirement, to section (f)(1)(vii) of the standard, for a shipped label to include the date a chemical is being released for shipment. OSHA believes the inclusion of this date will help manufacturers and distributors more easily determine when new hazard information is available. 

OSHA stated that this proposed chemical-release date requirement for the label came from feedback the agency began receiving shortly after the 2012 final rule went into effect. Many manufacturers described obtaining new hazard classification information for a chemical after they had already secured and palletized containers for shipment. In such cases, attempting to remove and replace the labels could have potentially placed workers at risk of injury or chemical exposure.  

The proposed change would enable manufacturers to provide the updated hazard information with the shipment for containers already released for shipment rather than needing to relabel the containers, resulting in greater protection of the chemical containers and workers. 

At an OSHA public hearing on the HazCom Standard held September 21–23, 2021, stakeholders provided a great deal of feedback on the changes contained within the NPRM. 

Commenters agreed that OSHA’s proposed changes would help avoid exposure and injury risks that may result from trying to remove labels from shipped containers already released for shipment but pointed out that sending updated shipped labels to users may create other risks. For instance, if end-users receive a stand-alone shipped label with the shipment, they may not affix it to the correct container. Some commenters advised including the information in shipping papers or in supplemental documentation instead. It remains to be seen whether, or how, OSHA will take into account this feedback in the process of developing a final rule. 

Changes in the Final Rule


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Trade Secret Provisions

Recap of the NPRM 

OSHA’s NPRM proposed to allow manufacturers, importers and employers to withhold a chemical’s actual concentration or concentration range on SDSs as trade secret/confidential business information (CBI).  

When an ingredient’s actual concentration or concentration range is claimed as a trade secret, OSHA would require the SDS to specify a concentration range selected from a prescribed list of ranges. 

For reference, the prescribed list is ranges is provided below. 

(A) From 0.1% to 1%;  

(B) From 0.5% to 1.5%;  

(C) From 1% to 5%;  

(D) From 3% to 7%;  

(E) From 5% to 10%;  

(F) From 7% to 13%;  

(G) From 10% to 30%;  

(H) From 15% to 40%;  

(I) From 30% to 60%;  

(J) From 45% to 70%;  

(K) From 60% to 80%;  

(L) From 65% to 85%; and  

(M) From 80% to 100%. 

OSHA noted that these prescribed concentration ranges are identical to the ranges required by Canada’s Hazardous Product Regulations (HPR). This is consistent with continuing efforts by the US-Canada Regulatory Cooperation Council (RCC) to further align each country’s hazard communication systems and requirements. 

When using these prescribed ranges to mask an existing concentration or concentration range, the prescribed range that is selected from above will need to be the narrowest range possible. OSHA provides some lee-way in applying multiple ranges in specific scenarios – if the exact concentration range is between 0.1% and 30%, and the exact range does not entirely fit in a single prescribed range, it is allowable to use two consecutive ranges between (A) and (G) above, provided that part of each prescribed range does not fall entirely outside of the exact concentration range.  

The NPRM proposed to allow manufacturers to use the CBIs only if they satisfy certain other requirements. For example, if a physician or other licensed health care professional (PLHCP) determines that a medical emergency exists and the specific chemical identity and/or specific concentration or concentration range of a hazardous chemical is necessary for emergency or first-aid treatment, the chemical manufacturer will need to disclose that information to the PLHCP, regardless of whether they’ve claimed a CBI. The chemical manufacturer can require the PLHCP to provide a written statement of need, and require them to sign a confidentiality agreement to protect the trade secret information. The OSHA NPRM also requires the chemical manufacturer to disclose specific details about the chemical in non-emergency situations, if the request is in writing and explains that the information is needed for occupational health reasons such as providing medical treatment to employees, conducting pre-assignment or periodic medical surveillance of exposed employees, assessing chemical exposure hazards and health effects of exposure, selecting personal protective equipment (PPE), or designing engineering controls or other protective measures to reduce exposure. 

The question of access to protected trade secret information hinges in part on who OSHA considers to be a PLHCP. OSHA’s NPRM offered a proposed definition of a PLHCP as “an individual whose legally permitted scope of practice (i.e., license, registration, or certification) allows the individual to independently provide or be delegated the responsibility to provide some or all of the health care services referenced in paragraph (i) of the standard.” There seems to be some leeway in that “provide or be delegated the responsibility to provide” part, and one reading of the text is that in OSHA’s view, it may come down to the actual job functions and responsibilities a person has, and whether those responsibilities include health care services or assessment of employee exposures.

Changes in the Final Rule


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Frequency of Future HazCom Revisions

Recap of the NPRM 

In the NPRM, OSHA requested public comment on whether the agency should adopt a schedule for updates to the HazCom Standard (e.g., every four years or every two revisions of GHS) or wait until there are significant changes to GHS before initiating rulemaking.  

OSHA’s idea here no doubt stems from the fact that it had been over 10 years since the last time they issued a final rulemaking to update HazCom. In the Federal Register notice for the NPRM, the agency observed that more frequently updating HazCom to align with newer revisions of the GHS may provide greater protection for workers and reduce uncertainty for manufacturers, distributors and employers. 

Stakeholders expressed a range of opinions on the options for schedules of future updates during the public hearings held from September 21–23, 2021. Some agreed that a fixed interval for future updates (e.g., every 2 years) would provide industry with more predictability, while others maintained it might be wasteful to commit to such a schedule, since there won’t necessarily be significant updates in that period of time.

Changes in the Final Rule


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