Thermal Work Environments – Part 11: OSHA’s Heat Rule

     The Occupational Safety and Health Administration (OSHA) has submitted its proposed occupational heat standard to the Office of the Federal Register (OFR) where it is pending official publication.  OSHA has made a draft version publicly available for review; it includes background information and justifications in addition to explanations of the requirements it creates.
     At nearly 1300 pages of “regulese” (a dialect of legalese), OSHA’s Notice of Proposed Rulemaking (NPRM) is a substantial document.  Though it only becomes official when published in the Federal Register, a document of this magnitude, in terms of both physical size and potential consequences, warrants a preview.  Any modifications that occur during OFR review are likely to be more aesthetic than substantive, ensuring the effort is not in vain.  To ease the burden of reviewing the massive NPRM, this installment of the “Thermal Work Environments” series provides an overview and summary of important points.

The Rulemaking Process
     At the conclusion of Part 5:  Managing Conditions in Hot Environments (12Jul2023), it was noted that OSHA had published an Advance Notice of Proposed Rulemaking (ANPRM) in October 2021.  The ANPRM, titled “Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings,” provided public notification of OSHA’s intention to promulgate a “heat rule” to supplant the General Duty Clause in assessments of hot conditions.
     A National Emphasis Program (NEP) followed in April 2022.  The NEP provides guidance for heat-related workplace inspections, including a list of industries targeted for enforcement.  Though heat-related citations continue to be made under the authority of the General Duty Clause, the NEP is clearly a step in the direction of a final heat rule.
     Publishing the ANPRM is only one step in a long, complex process, depicted in Exhibit 1.  It occurs at the end of Stage 1:  Making the Decision; the recent submission to OFR indicates that Stage 3:  Publishing the Proposed Rule has been initiated for the heat rule; the time between those two actions was approximately 30 months.  Given the duration estimates in the process outline, reports that the heat rule is expected to be in full effect in early 2025 seem excessively optimistic, though it is likely that the remainder of the process will be expedited to the extent possible.  The NEP is scheduled to expire in April 2025; it may be extended to ensure that heat-related issues receive sufficient attention until the new heat rule is finalized.

The NPRM in Brief
     The complete text of the NPRM is available from the OSHA website or the OFR Rulemaking Docket website.  Links to reference documents, a record of comments on the proposed rule, and other information are also provided in the docket.  The summary below parallels the organization of the NPRM; the headings mirror those of its major sections.  Page numbers are provided to facilitate detailed review of sections when necessary.

I. Executive Summary (p. 6)
     In customary fashion, the executive summary provides a preview of the document’s contents in a manner that is justifiably ignored.  Perhaps more useful is the 100-word summary (p. 1) mandated by the Providing Accountability Through Transparency Act of 2023 (S.111):
“OSHA is proposing to issue a new standard, titled Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings. The standard would apply to all employers conducting outdoor and indoor work in all general industry, construction, maritime, and agriculture sectors where OSHA has jurisdiction, with some exceptions. It would be a programmatic standard that would require employers to create a plan to evaluate and control heat hazards in their workplace. It would more clearly set forth employer obligations and the measures necessary to effectively protect employees from hazardous heat. OSHA requests comments on all aspects of the proposed rule.”

II. Pertinent Legal Authority (p. 10)
     This section summarizes the authority granted to OSHA by the Occupational Safety and Health Act of 1970 and cites relevant case law.  Discussions of the determinations of significant risk, technological and economic feasibility, and high degree of employee protection are also included.  It is these determinations that are used to justify regulations promulgated pursuant to the Act.

III. Background (p. 17)
     A history of OSHA’s heat-related protection efforts, including use of Regional and National Emphasis Programs (REPs and NEPs), inspection authority, and the General Duty Clause is provided in this section.  Development of the NIOSH Criteria for a Recommended Standard – Occupational Exposure to Heat and Hot Environments, from the original in 1972 to its latest revision (2016) and the ACGIH TLVs is also cited, establishing heat exposure as a known occupational hazard.
     Heat protection guidelines developed by standards organizations (e.g. ISO, ANSI/ASSP), six states [CA, CO, MD (proposed), MN, OR, WA], and the U.S. Armed Forces are discussed, further bolstering the justification for a unified standard.  Activities of advisory committees and other meetings are presented, demonstrating adherence to the process outlined above.

IV. Health Effects (p. 44)
     Information similar to much of that presented in this section can be found in Part 3:  Heat Illness and Other Health Effects (14Jun2023) and the discussion of heat balance in Part 2:  Thermoregulation in Hot Environments (31May2023).  The NPRM provides greater detail, however; for example, a discussion of reproductive health effects, foregone in this series, is included.
     Additional information on classification of health effects is presented; this is most useful for research and reporting purposes.  Day-to-day management of a hot work environment is unlikely to utilize this information in any meaningful way.

V. Risk Assessment (p. 145)
     Subsection A presents the data analysis that led OSHA to conclude that a heat rule is needed.  Subsection B presents the analysis driving the selection of initial and high heat triggers defined in the standard.  Numerous studies are cited in Subsection C.  The overarching theme of the discussion is the reduction of risk of heat-related illness and injury (HRI) through the use of eight categories of techniques.  These categories, or “heat safety topics,” are:  hydration, environmental monitoring, emergency procedures and plans, body cooling, acclimatization, textiles/PPE, physiological monitoring, and heat hygiene.  Examples of each are provided; some are the subjects of detailed discussion.

VI. Significant Risk (p. 286)
     Determinations of significant risk and material harm are revisited in this section.  OSHA concludes that the potential health effects discussed in Section IV constitute material harm, the occurrence rate of HRIs constitutes significant risk, and compliance with the proposed standard substantially reduces this risk.

VII. Explanation of Proposed Requirements (p. 294)
     The NPRM proposes the addition of §1910.148 Heat Injury and Illness Prevention to 29 CFR Part 1910 Subpart J – General Environmental Controls.  NPRM subsection headings correspond to paragraphs of §1910.148.
(a) Scope and application (p. 294):  The heat rule applies to all employers except those described in this paragraph.  Employees exempt from the rule’s requirements include firefighters and other emergency responders, remote (i.e. “work from home”) and sedentary workers, and those whose exposures are of short duration.
     In the NPRM, OSHA declares that the rule applies to all employers subject to its jurisdiction.  However, Part 1910 applies only to General Industry; subjecting specific industries, such as maritime and construction, to this rule requires amendment of other regulations.  OSHA proposes that 29 CFR 1910.148 be incorporated by reference in other Parts of the code to impose the same requirements on those industries.
(b) Definitions (p. 304):  §1910.148 briefly defines several terms; readers of this series will be familiar with most of them.  New terms include initial heat trigger and high heat trigger; these form the foundation of the heat rule.  The initial heat trigger is a heat index (HI) of 80° F or wet bulb globe temperature (WBGT) equal to the NIOSH Recommended Alert Limit (RAL).  The high heat trigger is an HI of 90° F or WBGT equal to the NIOSH Recommended Exposure Limit (REL).
     The brief definitions provided in the code are expanded with further discussion in the NPRM.  HI and WBGT were introduced in Part 4:  A Measure of Comfort in Hot Environments (28Jun2023); detailed explanations of the NIOSH RAL and REL can be found in the Criteria for a Recommended Standard (NIOSH, 2016).
(c) Heat Injury and Illness Prevention Plan (p. 314):  Paragraph (c) requires every employer not exempted in paragraph (a) to develop a heat injury and illness prevention plan (HIIPP) and make it readily available to all employees in a language they understand.  The HIIPP must define the following:

• All activities covered by the HIIPP.
• All policies and procedures used to comply with the heat rule.
• The heat metric used (i.e. HI or WBGT).
• Additional policies and procedures required for use of impermeable PPE.
• The identity of each safety coordinator granted authority to ensure compliance with the heat rule.
• Heat exposure monitoring plan [see paragraph (d)].

The HIIPP must be reviewed and updated as necessary on an annual basis, at minimum, and each time an HRI results in death, time lost, medical treatment, or loss of consciousness.
     In 2018, OSHA commissioned the creation of a Model Heat Illness Prevention Plan, among other deliverables.  Using this model as a guide for one’s own HIIPP development demands careful consideration of the heat rule’s requirements, however.  “It is not designed to meet state, local or other regulatory requirements on heat stress” and “It does not necessarily reflect the views or policies of the U. S. Department of Labor…” are repetitive disclaimers in its text.
     An approach to heat illness prevention program development was also outlined in Part 5:  Managing Conditions in Hot Environments (12Jul2023).  A future revision will incorporate new guidelines, improving alignment with the finalized OSHA heat rule.   If your organization currently has an HRI-prevention plan in place, it must also be updated to comply with §1910.148.  Proactive review, prior to rule finalization, will ease the transition to the new requirements.
(d) Identifying heat hazards (p. 325):  Outdoor work areas can be monitored with onsite measurements of temperature and humidity (to calculate HI) or WBGT.  Data provided by the National Weather Service (NWS) can be substituted for onsite measurements.  A worksite can be exempted from monitoring by maintaining at all times all controls required when the high heat trigger is exceeded.
     The first and third options are also available to indoor work areas; NWS data are not valid for indoor settings.  If monitoring is conducted, a plan must be defined and reviewed in connection with changes in processes, equipment, etc. to ensure adequate protection is maintained.  Substantial increases in outdoor temperature, such as that occurring during a heat wave, should also prompt review of the monitoring plan.
(e) Requirements at or above the initial heat trigger (p. 334):  A summary of this section would closely resemble the proposed text of §1910.148; further discussion here quickly becomes redundant.  The requirements defined in this section are at the core of the heat rule; as such, it warrants reading in its entirety.  Of particular interest to many will be the requests for comments that OSHA has placed throughout the NPRM.  The public comment period provides an opportunity to those who have not yet weighed in to offer feedback or express concerns about aspects of the proposed rule.
(f) Requirements at or above the high heat trigger (p. 377):  Remarks pertaining to paragraph (e), above, are equally applicable to this section.
(g) Heat illness and emergency response and planning (p. 402):  The information provided in this section is not groundbreaking, but it is quite detailed.  The types of information and level of detail required in the emergency response portion of the HIIPP is made abundantly clear.
(h) Training (p. 410):  Training requirements are fairly straightforward; the text of §1910.148 could be used as a checklist to ensure that all required topics are adequately covered in any training materials developed.
(i) Recordkeeping (p. 425):  Indoor work area measurement data must be retained for a minimum of six months.  The NPRM describes potential uses for historical measurement data.
(j) Requirements implemented at no cost to employees (p. 427):  The paragraph title leaves little else to say.
(k) Dates (p. 434):  Dates of effectivity and required compliance are established upon publication of a final rule in the Federal Register.  The rule becomes effective 60 days after publication and compliance is required 150 days after publication (90 days after effectivity).
(l) Severability (p. 435):  This section provides typical contract and regulation boilerplate specifying that each provision of the heat rule is enforceable independent of the others.  That is, if any provision is found, or becomes, unenforceable, there will be no impact on the remaining provisions or requirements.

VIII. Preliminary Economic Analysis and Initial Regulatory Flexibility Analysis (p. 438)
     This section contains an extensive presentation of data used to support the decision to develop a heat rule and, ultimately, its content.  A list of industries anticipated to be affected by the rule is provided; it is broad and inclusive.
     Compliance cost estimates are provided on a requirement-by-requirement basis and tabulated by industry and geographic region.  These estimates can be used for preliminary budgeting, though every organization should conduct its own assessment to develop estimates of one-time and recurring compliance costs.
     Estimates of compliance costs also inform the economic feasibility analysis, on which the NPRM provides another lengthy presentation of data and explication.  On the benefit side of the analysis, monetized estimates of the benefits of reduced incidence of HRIs and improved health are given.  A range of values is provided by high, low, and anticipated estimates of the heat rule’s effectiveness in reducing the frequency and severity of HRIs.
     The section concludes with a set of appendices that provide additional background information relevant to previous subsections.  Of these, Appendix A – Description of the Cost Savings Approach (p. 1012) may be most useful; it could be used to improve analysis of the rule’s anticipated economic impact on an organization.

IX. Technological Feasibility (p. 1099)
     Declaring the heat rule requirements technologically feasible is a straightforward matter.  The technologies involved are well-known and readily available, from fans, coolers, and air conditioning to heat index calculators and universal and specialized measurement (e.g. WBGT) devices.  Where technology falls short, administrative controls can be used to close the gaps.

X. Additional Requirements (p. 1132)
     This section describes procedures required of regulatory agencies.  This information is useful for deepening one’s understanding of the rulemaking process, but is not particularly useful for practical purposes of implementation.  One exception is subsection I:  OMB Review Under the Paperwork Reduction Act of 1995 (p. 1146), where requirements for the collection of information are defined.  These requirements are tabulated in summary format in Table X.I-1 (p. 1149) which can be used as a checklist to ensure that all required information is recorded properly.

XI. Authority and Signature (p. 1155)
     The agency’s legal authorization to promulgate the proposed rule is reiterated and the responsible director is identified.

Amendments to Standards (p. 1157)
     Appended to the NPRM, this section contains the text of proposed amendments to 29 CFR Parts 1910, 1915, 1917, 1918, 1926, and 1928.  For the most part, the code is straightforward and understandable.  Where clarity is needed, consult the expanded discussion in Section VII.

References (p. 1176)
     A comprehensive list of references is provided, many of which are hyperlinked.  Links to some documents are also available on the Rulemaking Docket, but only a small subset.

The End (p. 1276)
     Compressing nearly 1300 pages into a digestible overview required large portions of the NPRM document be given short shrift.  Doing so is certainly defensible from a practitioner’s point of view.  There is a great deal of background information and data presented that, while required for the rulemaking process, offers little to a pragmatic business owner or manager.
     Despite the extensive review process to which the heat rule has already been subject, the final rule could differ slightly from that proposed in the NPRM.  Upon publication of the final rule in the Federal Register, it should be reviewed to ensure that any substantive changes are incorporated in an organization’s HIIPP, budgeting, and other planning activities.


     For additional guidance or assistance with complying with OSHA regulations, developing a heat injury and illness prevention program, or other Operations challenges, feel free to leave a comment, contact JayWink Solutions, or schedule an appointment.

     For a directory of “Thermal Work Environments” entries on “The Third Degree,” see Part 1:  An Introduction to Biometeorology and Job Design (17May2023).

References
[Link] General Duty Clause; Occupational Safety and Health Act, Sec. 5.
[Link] Advance Notice of Proposed Rulemaking:  “Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings.”  OSHA; October 27, 2021.
[Link] National Emphasis Program – “Outdoor and Indoor Heat-Related Hazards.”  OSHA; April 8, 2022.
[Link] Notice of Proposed Rulemaking:  “Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings.”  OSHA; July 2, 2024.
[Link] Rulemaking Process (Flowchart); OSHA.
[Link] Rulemaking Docket:  “Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings;” OSHA.
[Link] S.111 - Providing Accountability Through Transparency Act of 2023.
[Link] Occupational Safety and Health Act of 1970.
[Link] “NIOSH Criteria for a Recommended Standard Occupational Exposure to Heat and Hot Environments.”  Brenda Jacklitsch, et al.  National Institute for Occupational Safety and Health (Publication 2016-106); February 2016.
[Link] “Threshold Limit Values for Chemical Substances and Physical Agents.”  American Conference of Governmental Industrial Hygienists (ACGIH); latest edition.
[Link] 29 CFR Part 1910 Subpart J.
[Link] Model Heat Illness Prevention Plan.  University of Houston Clear Lake; 2018.

Jody W. Phelps, MSc, PMP®, MBA
Principal Consultant
JayWink Solutions, LLC
[email protected]