Industrial Hygiene Program Playbook (2026)

Industrial hygiene (IH) is the quantitative core of EHS. Lower OELs (lead and diisocyanates in the EU, revised in 2024, with the Member States' transposition date of 9 April 2026 now passed; check your national rules), ESRS S1 health and safety disclosure under CSRD and long-latency occupational-disease risk all point the same way. A workable 2026 baseline is an IH programme built on AIHA exposure-assessment strategy, with SEGs, documented statistical decisions and a defined route to occupational health review, whether it runs on paper or in software.

This playbook walks the full lifecycle — characterise, plan, sample, decide, control — and shows where industrial hygiene software can fit.

1. The 2026 IH pressures

Three pressures are reshaping IH programmes:

• Lower OELs. Respirable crystalline silica (see the glossary entry on the silica standard): 50 µg/m³ (8-hour TWA) under OSHA 29 CFR 1910.1053 and 0.1 mg/m³ (respirable fraction) in the EU Carcinogens, Mutagens or Reprotoxic Substances Directive (CMRD), added by Directive (EU) 2017/2398. Directive (EU) 2024/869 set lead at 0.03 mg/m³ (inhalable fraction) under the CMRD and diisocyanates at 6 µg NCO/m³ (8 hours) with a 12 µg NCO/m³ short-term limit under the Chemical Agents Directive (10 and 20 µg NCO/m³ apply until 31 December 2028).
• CSRD ESRS S1 disclosure. For undertakings in scope where own workforce is a material topic, the ESRS S1 health and safety metrics (fatalities, recordable work-related accidents, cases of recordable work-related ill health and days lost) are reported in the sustainability statement. Assurance on sustainability reporting rests on Article 26a of Directive 2006/43/EC, and Directive (EU) 2026/470 postpones the Commission's deadline for adopting the limited assurance standards to 1 July 2027. Cases identified through medical surveillance count as recordable ill health. In the 2023 ESRS, which apply up to financial year 2026, these are S1-14 and AR 94 (Delegated Regulation (EU) 2023/2772); from financial year 2027 the revised ESRS move them to S1-13 and AR 27 (Delegated Regulation (EU) 2026/1563). An IH dataset is a primary source for them.
• Long-latency disease tail. Long-latency diseases (silicosis, hearing loss, hand-arm vibration syndrome, occupational asthma) can surface years after exposure; the noise and HAV guide covers two of them. SEG-and-sampling documentation is the record that defends the programme.

2. Similar Exposure Groups (SEGs) — the foundation

An SEG is a group of workers who share the same exposure profile because they share the same job, task, agent and control environment. SEGs are the unit of management in modern IH because they let you sample once and apply the result to many workers.

A clean SEG definition has four dimensions:

• Job / role (machine operator, welder, lab technician)
• Task (grinding, MIG welding on stainless, weighing reagents)
• Agent (respirable crystalline silica, hexavalent chromium, hexane)
• Control state (LEV in place, RPE worn, isolation booth)

Common mistakes: defining SEGs by department rather than task (too broad), forgetting the control state (mixing LEV-on and LEV-off workers into one SEG), and ignoring shift length (12-hour shifts may need an adjusted OEL, for example with the Brief & Scala model).

3. AIHA exposure-assessment strategy

AIHA's A Strategy for Assessing and Managing Occupational Exposures (4th ed.) is the operating manual. Six steps:

1. Basic characterisation — agents, workers, controls.
2. Exposure assessment — qualitative banding for every SEG.
3. Acceptable / uncertain / unacceptable decision — based on data sufficiency and 95th-percentile vs OEL.
4. Further information gathering — sampling, modelling.
5. Control & re-assessment — if unacceptable.
6. Re-assessment cadence — based on decision and stability.

The 95th-percentile rule matters because the decision statistic of the AIHA Strategy (4th ed.) aims for at least 95% confidence that the true 95th percentile is below the OEL (as summarised in an AIHA webinar handout), so a single sample below the OEL does not by itself show that the SEG is acceptable. Enough samples per SEG to reach that confidence, log-normal distribution, IHSTAT or Bayesian decision tools.

4. Sampling plans that actually work

A 2026 sampling plan covers:

• Strategy — random, worst-case or compliance. Worst-case for screening; random for statistical decision; compliance for regulatory enforcement defence.
• Sample size — enough per SEG to reach the confidence the acceptable/unacceptable decision needs (section 3); more for borderline.
• Method — NIOSH or OSHA method per agent, with chain of custody and the laboratory's own quality controls such as blanks and spikes.
• Equipment — calibrated pumps and dosimeters, barcode-linked to worker and SEG in the IH software.
• Lab — accredited (AIHA LAP or ISO/IEC 17025), with a defined route for results to reach the record (an API, a file import or manual entry).

Evaluate mobile capture against the existing process using chain of custody, identification, offline recovery and correction history; the record medium alone does not establish data quality.

5. Decisions, mixture rules and trends

When results come back:

• 95th-percentile vs OEL. The exposure control categories of the AIHA Strategy band the 95th percentile at <1%, <10%, 10–50%, 50–100% and >100% of the OEL (categories 0 to 4), with more controls recommended at each step (as summarised in the AIHA webinar handout).
• Mixture rule. Sum Ci/OELi across the agents in a mixture, a common trap for solvents. OSHA's equivalent-exposure formula in 29 CFR 1910.1000(d)(2)(i) applies to any mixture of the air contaminants it covers, with no target-organ condition, and the sum must not exceed 1.
• Mann-Kendall trend per SEG over time — detects programme drift before it becomes a finding.
• Adjusted OELs for extended shifts, for example with the Brief & Scala model.

Ask each vendor to demonstrate the required calculations, method versions and review workflow; do not assume every platform performs these analyses. The capability map shows how consistently these capabilities are documented across the profiles on this site.

6. Medical surveillance triggers

Agree the surveillance programme with a competent occupational hygienist and occupational health professional for the actual substance, exposure and jurisdiction. An AIHA exposure category is a risk-management aid, not a universal legal or clinical trigger; crossing 50% of an OEL does not by itself determine which examination a worker needs.

Configure the workflow to:

• Flag the applicable exposure result and its uncertainty for qualified review.
• Record the review decision, relevant requirement and responsible occupational-health service.
• Track required follow-up while restricting identifiable health information to authorized roles.

Use occupational health software to evaluate the case-management handoff and incident management for exposure events. Demonstrate access boundaries before linking clinical records to a wider action log.

7. KPIs your board should see

• Number of SEGs with acceptable / uncertain / unacceptable decisions
• 95th-percentile exposure as % of OEL per agent family
• Overdue medical surveillance %
• Sampling plan completion %
• Open CAPAs from unacceptable decisions
• ESRS S1 metric: cases of recordable work-related ill health

8. Checks to run on your own programme file

The list below is a self-review prompt, not a statistic about what auditors find.

• SEGs not reviewed annually
• Sample size below AIHA sufficiency
• 95th-percentile not documented
• Surveillance triggers not closed
• OEL library not updated for current ACGIH TLVs / EU IOELVs
• No qualitative assessment for agents without sampling data

Whether a given platform flags any of these automatically is a question for its documentation and a demonstration.

9. 90-day rollout

• Weeks 1–3 — Baseline. Agent register, SEG definition, historical sampling import, OEL library, occ-health roster sync.
• Weeks 4–7 — Pilot. One site, one agent family end-to-end.
• Weeks 8–12 — Scale. Additional sites and agents, occ-health integration live, CAPA workflow, KPI dashboard, ESRS S1 feed.

Worked example: a fabrication shop

This is an illustration with invented numbers, not data from any site. A shop has eight welders who weld stainless steel in one bay with local exhaust ventilation and four who weld the same material outdoors without it. Treating all twelve as one SEG would blend two control states, so the programme records two SEGs: bay welders and outdoor welders. Each gets its own sampling plan and its own decision.

For solvent work in the paint area, the mixture rule needs only arithmetic. If three solvents measure at 40%, 30% and 20% of their own limits, the sum is 0.4 + 0.3 + 0.2 = 0.9, which is below 1 and passes the mixture check. A fourth solvent at 20% takes the sum to 1.1, which does not, even though every individual result is under its limit. The limits used in any real calculation must be the ones that apply in your jurisdiction.

What to ask a vendor about IH records

• Can I define SEGs by job, task, agent and control state, and move a worker between them with a dated history?
• Which statistical methods and OEL sources does the product document, and can I see the formula and version used for a decision?
• How are laboratory results brought in, and what happens when a result is corrected or a method changes?
• Who can see a surveillance referral, and can that visibility be limited to occupational health roles?

For related guides, see the occupational health software guide, the chemical management guide, the glossary entry on the hierarchy of controls and the posts on noise and hand-arm vibration compliance and heat stress management. The glossary entry on safety data sheets defines the supplier document that an agent record usually starts from.

FAQ

Do I need a separate IH module or is general EHS enough? Check whether the general EHS product documents SEGs, sampling sufficiency, mixture rules and surveillance referrals. If you manage regulated agents or many exposure-relevant workers and it does not, evaluate a dedicated module.

How big should an SEG be? Small enough that exposures are genuinely similar, large enough that a practical number of samples represents the population.

How often should we re-sample? Set the interval from the SEG's decision and how stable the process is (step 6 of the AIHA cycle), re-assess after any change, and keep sampling unacceptable SEGs until controls bring them to acceptable.

Where does the chemical management 2026 module fit? Chemical management owns the SDS and inventory; IH owns the agent-to-worker exposure. They share the agent register.

Is IH inside ISO 45001? ISO 45001 specifies requirements for an OH&S management system, which covers exposure controls; ISO 45003 gives guidelines for managing psychosocial risk within it. Ask your certification body what exposure evidence it expects to see.

Can we feed IH data into ESRS S1? Partly. Under the 2023 ESRS, occupational illness from IH agents counts towards cases of recordable work-related ill health, including cases identified through medical surveillance (Delegated Regulation (EU) 2023/2772, S1-14, AR 92 and AR 94). From financial year 2027 the revised ESRS (Delegated Regulation (EU) 2026/1563, S1-13) drop the AR 92 list of examples; its definitions describe recordable ill health as illness caused or made worse by workplace factors, or caused primarily by exposure at work to a physical, organisational, chemical or biological risk factor, where it results in death or absence from work, and cases identified through medical surveillance are still included (AR 27). The revised standard applies to financial years beginning on or after 1 January 2027. Exposure incidents and surveillance completion are not ESRS S1 datapoints in either version, though they are useful internal KPIs.

Sources

• 29 CFR 1910.1053, Respirable crystalline silica and 29 CFR 1910.1000, Air contaminants (OSHA)
• Directive (EU) 2017/2398 and Directive (EU) 2024/869 amending the Carcinogens, Mutagens or Reprotoxic Substances Directive and the Chemical Agents Directive (EUR-Lex)
• Commission Delegated Regulation (EU) 2023/2772, ESRS S1, Commission Delegated Regulation (EU) 2026/1563, revised ESRS and Directive (EU) 2026/470 (EUR-Lex)
• AIHA: A Strategy for Assessing and Managing Occupational Exposures, 4th edition, exposure risk assessment tools including IHSTAT and Making Accurate Exposure Risk Decisions, video 2 handout
• Brief RS, Scala RA. Occupational exposure limits for novel work schedules. American Industrial Hygiene Association Journal, 1975
• NIOSH Manual of Analytical Methods and OSHA sampling and analytical methods
• ISO/IEC 17025:2017, ISO 45001:2018 and ISO 45003:2021 (iso.org)

Updated 4 October 2026: the OSHA silica and mixture-formula statements, the EU silica, lead and diisocyanate limits, the ESRS S1 references (2023/2772 and 2026/1563) and the AIHA decision statistic and exposure categories were re-checked against the primary texts; the assurance citation and the revised ESRS definition of recordable ill health were corrected, unsupported statements about what software does automatically were reworded, and a worked example and vendor questions were added.

Corrected 23 September 2026: statistics without a primary source were sourced, labelled as examples or removed, and the regulations cited now link to their official texts.