OSHA's 2026 Heat NEP High-Hazard Industries List: The 55-Industry Targeting Structure and How to Know If You're On It

When OSHA reissued its Heat National Emphasis Program on April 10, 2026, most coverage stopped at the headline: the target list shrank from 70-plus industries to 55. That number is the easy part. The part that decides whether an unannounced inspector shows up at your facility this summer is the composition of that list — which industries came off, which got added, and the data OSHA used to build it. The reissued directive (CPL 03-00-024) also added two appendices and a mandatory outreach window that the first round of reporting largely missed. This is the structural detail behind the 2026 Heat NEP high-hazard industries list, written for the people who have to act on it.

If you ran the prior Heat NEP playbook and assumed your facility’s status carried forward, stop. The list was rebuilt from scratch on four years of injury and enforcement data. Your NAICS code may have fallen off — or landed on it for the first time.

What is OSHA’s 2026 Heat NEP and when did it take effect?

OSHA reissued the Heat National Emphasis Program (CPL 03-00-024) on April 10, 2026, effective immediately for five years (through approximately 2031). It replaced the 2022 program that lapsed April 8, 2026, and targets 55 high-hazard industries for programmed heat inspections under General Duty Clause authority.

An NEP is not a regulation. It is an enforcement-targeting directive that authorizes programmed — unannounced — inspections in listed industries and structures how compliance officers handle heat hazards found during any inspection, listed or not. Because there is still no federal heat standard, OSHA continues to cite heat exposure under Section 5(a)(1) of the OSH Act, using ACGIH threshold limit values and NIOSH criteria as evidence of a recognized hazard. The directive runs immediately and does not wait for a comment period or a phase-in. The first National Weather Service heat advisory of the season is your real deadline.

How many industries are on the 2026 Heat NEP target list?

55 industries are targeted in Appendix A — down from 70-plus in the 2022 version. The rebuild removed 46 previously targeted industries, added 22 new ones, and retained 33, based on 2021–2024 BLS injury data and 2022–2025 OSHA heat citations.

Those three numbers do not add to 55 by accident, and they tell you something the headline does not. The 33 retained industries are facilities OSHA already considered high-hazard and still does — no relief there. The 22 additions are industries that earned their way onto the list on recent data, and many of them are not the manufacturing subsectors people associate with heat enforcement. The 46 removals are the real news for a specific set of employers: if your industry came off, your programmed inspection probability for 2026–2031 dropped materially. That is a genuine carve-out, not a softening of the program — and it does not touch your General Duty Clause exposure, which still applies to every employer with a recognized heat hazard regardless of list status.

How do I know if my facility is on the Heat NEP target list?

Match your primary 4-digit NAICS code against Appendix A of CPL 03-00-024. Confirmed targeted codes include 3261 (plastics product manufacturing), 5617 (services to buildings and dwellings), 6241 (individual and family services), 8111 (automotive repair and maintenance), and 4412 (other motor vehicle dealers). Even unlisted worksites face inspection if a visible heat hazard is observed.

That confirmed-code list makes the point that this is no longer a manufacturing-only program. NAICS 6241 captures adult day care and home-care operations. NAICS 4412 captures used-car, RV, and motorcycle dealers. NAICS 8111 captures the repair bay at every shop in your region. If you classified your facility as “not a manufacturer, so not our problem” under the 2022 list, that assumption is wrong under the 2026 list.

Run the check in two steps. First, find your primary 4-digit NAICS — the one on your most recent reporting, not a guess. Second, locate it in Appendix A of the directive PDF and determine whether it is newly added or retained. That distinction controls your timeline, which is the next question.

What data did OSHA use to choose the 55 industries?

OSHA rebuilt the list using BLS heat-illness counts and rates and days-away/restricted/transferred data from 2021–2024, OSHA severe-injury reports (hospitalizations and deaths) from 2021–2024, and its own heat-related General Duty Clause citations and Hazard Alert Letters from 2022–2025.

This methodology is why the “find your NAICS” answer matters more than a static list. OSHA did not pick these industries on reputation. It picked them on three converging data streams: where workers are actually getting sick (BLS), where they are getting hospitalized or killed (severe-injury reports), and where OSHA has already found and acted on heat hazards (its own citation and HAL record). An industry made the 2026 list because it showed up across those datasets in the most recent four years. If your sector’s injury numbers climbed between 2021 and 2024, that is the mechanism that put you on the list — and the same mechanism that will keep the list current at the next renewal.

What is the 90-day outreach window in the 2026 Heat NEP?

Newly added industries receive a mandatory 90-day outreach period — mailings, webinars, or on-site compliance assistance — before OSHA conducts any programmed heat inspection. Employers should use that window to build or strengthen their heat program against the Appendix I criteria and document the effort.

This is the single most actionable change in the reissue, and it only applies if your NAICS is one of the 22 additions. Retained industries get no grace period — programmed inspections can occur now. The 90-day clock is a build window, not a waiting period. Treat it as the time you have to stand up a written program, run acclimatization for new workers, train supervisors, and put a documentation trail in place before the first programmed inspection is legal. Employers who treat the outreach contact as informational rather than as a starting gun will burn the window and meet the inspector with the same gaps they had on day one.

What are Appendix I and Appendix J in the new Heat NEP?

Appendix I gives inspectors a structured framework to evaluate an employer’s heat illness prevention program — which makes it usable as a self-audit checklist. Appendix J consolidates guidance on when to issue a citation versus a Hazard Alert Letter and how to document General Duty Clause violations.

Read together, these two appendices remove most of the guesswork about what an inspection produces. Appendix I is the inspector’s evaluation grid — water access, rest and shade, acclimatization protocol, training records, monitoring with defined action levels, emergency response. If you score your own program against Appendix I before OSHA does, you will see your gaps in the same order the inspector will. Appendix J formalizes the citation-versus-Hazard-Alert-Letter decision that, under the prior program, drove a roughly 23-to-1 outreach-to-citation ratio. The pattern Appendix J encodes is consistent: a written, followed program tends toward a Hazard Alert Letter and education; no written program, no acclimatization policy, or a prior violation tends toward a citation. The documentation is the dividing line.

What triggers a programmed heat inspection now that the quota is gone?

The 2026 reissue removed the numerical inspection goal. Inspections are now driven by industry classification (Appendix A), National Weather Service heat-index categories, the 80°F “heat priority day” threshold, prior citation history, complaints, referrals, and severe-injury reports — not a fixed regional quota.

This is a correction worth being precise about, because the early reporting on the renewal — including iSi’s own first post on the manufacturing renewal — described the change as OSHA “replacing” the 80°F heat-index trigger with NWS advisories. That is not what the directive does. The 2026 reissue retains the 80°F heat-index “heat priority day” reference and runs it alongside NWS heat-index categories. What changed is the removal of the numerical inspection quota, not the temperature threshold. The practical effect: there is no longer a fixed number of inspections a region must hit, so enforcement should be fewer but better-targeted — concentrated on facilities with documented hazards, prior history, or a complaint on file, rather than spread to make a count.

What does a heat illness prevention program need to include?

A compliant program is a written, facility-specific plan covering water, rest, shade or cooling, an acclimatization schedule for new and returning workers, annual employee and supervisor training, heat-index monitoring with action levels, and a documented emergency-response procedure. Acclimatization is the most frequently cited missing element.

Build it to mirror Appendix I, because that is the framework you will be measured against. Seven elements carry the weight. A written program that names high-heat areas and assigns a responsible manager. Cool drinking water at roughly one quart per employee per hour of heat work. Scheduled and as-needed rest in shaded outdoor or climate-controlled indoor areas. An acclimatization protocol — commonly 20% exposure on day one, building 20% per day over about two weeks — for new and returning workers. Annual training for employees and supervisors on symptoms, response, and emergency procedures. Heat-index monitoring with defined action levels, supported by the OSHA-NIOSH Heat Safety Tool and the 80°F “heat priority day” reference. A documented emergency-response procedure. The eighth element is the one that converts the other seven from practice into defense: documentation. Undocumented practices read to an inspector as no program at all.

What are the OSHA penalties for a heat violation in 2026?

Up to $16,550 per serious violation, $165,514 per willful or repeat violation, and $16,550 per day for failure to abate. There was no 2026 inflation increase — the October 2025 CPI-U was unavailable due to the government shutdown and OMB cancelled the adjustment — so 2025 levels carry forward.

The figures are unchanged from 2025, but the exposure is not theoretical. A single willful heat citation at $165,514 dwarfs the cost of building the program that prevents it. The failure-to-abate provision is the one that compounds: $16,550 per day past the abatement date means a program gap you cannot close fast accrues penalty every day it stays open. The no-inflation-adjustment story is not relief — it is a one-year pause driven by a data gap, not a policy decision to ease enforcement.

Do small employers get a break on heat-violation penalties?

Yes. Under Field Operations Manual Chapter 6 revisions effective July 14, 2025, the maximum size-based penalty reduction now applies to employers with 1–25 employees (previously 1–10). Employers with 11–25 employees moved from a 60% to a 70% reduction, the 80% serious-willful reduction now covers employers with 20 or fewer employees, and the history reduction rose from 10% to 20%.

For a small manufacturer, repair shop, or home-care operator newly on the list, these reductions change the math materially — but only on the penalty, not on the obligation. A reduced penalty on a willful violation is still a willful violation on your record, and the reduction does nothing to address the underlying hazard that injured a worker. The reductions make the cost of a citation more survivable for a small employer; they do not make skipping the program a defensible choice.

Is there a federal heat standard yet?

No. The proposed Heat Injury and Illness Prevention rule (NPRM, 89 FR 71374) is in post-hearing rulemaking with no final rule. Until one issues, the Heat NEP combined with the General Duty Clause is OSHA’s enforcement mechanism.

This is why program documentation, not compliance with a specific numeric standard, is what OSHA evaluates. There is no rule citing a required wet-bulb globe temperature action level or a mandated rest-break schedule to comply with. Instead, OSHA must prove a recognized hazard under Section 5(a)(1), and it uses Appendix I to judge whether your program addresses that hazard. The absence of a final standard does not lower your exposure — it shifts the question from “did you meet the threshold in the rule” to “did you have a program that addresses a hazard OSHA can show you recognized.” A documented Appendix I-aligned program is the answer to that question.

Does the Heat NEP apply in Kansas, Oklahoma, Texas, Missouri, and Nebraska?

Yes. Federal OSHA administers Kansas, Oklahoma, Texas, Missouri, and Nebraska for private-sector employers, so the federal Heat NEP applies directly. None of these states has its own general-industry heat standard, so the NEP and the General Duty Clause are the operative authority. NWS heat advisories typically begin in May or June across the region.

For iSi’s core five-state footprint, that means there is no state-level program softening or complicating the picture — the federal directive is the whole story. The timing matters: with advisories landing in May and June, retained-industry employers in these states needed an operational program before the season started, and newly added employers are inside their 90-day windows now. Multi-state clients with operations in California, Oregon, Washington, Minnesota, or Colorado face an additional layer — those state-plan states run their own, generally more prescriptive heat rules in parallel — but for facilities in the iSi region, the federal NEP is the authority to build against.

What this means for your facility before the next heat advisory

The 2026 Heat NEP did not just renew — it re-sorted who OSHA is looking at and gave a specific set of newly targeted employers a finite window to get ready. Three actions follow directly from the structure above. Find your 4-digit NAICS in Appendix A and determine whether you are retained (program operational now) or newly added (90-day window). Score your existing program against Appendix I, with acclimatization first, since it is the most-cited gap. Build the documentation trail that turns your practices into an inspection defense, because under Appendix J the written record is what separates a Hazard Alert Letter from a citation.

This is the work iSi does for manufacturers and industrial operators whose safety manager owns heat compliance on top of everything else. Heat illness prevention program development, Appendix I gap assessment, acclimatization protocol design, and supervisor training are exactly the kind of industrial hygiene and safety consulting work that plugs into an existing EHS team without adding a $130,000–$195,000 headcount. A single willful heat citation runs up to $165,514. An Appendix I gap assessment that closes the exposure before the inspector arrives costs a fraction of that — and it produces the documented program that turns an inspection into a Hazard Alert Letter instead of a fine.

Find your NAICS in Appendix A, then talk to us about a heat program gap assessment before the next advisory hits your region.