// regulation → measurement

Workplace: exposure limits (2017/164, 2019/1831) & ATEX (1999/92/EC, 2014/34/EU)
Toxic and combustible gas detection at the workplace

Two families of rules: exposure limits protect people from toxic gases; ATEX protects the plant from explosions. Both end in a detector with an alarm — and in the record that it was calibrated.

Plant safety managersRefrigeration (NH₃) operatorsFumigators (SO₂F₂, CH₃Br)Battery/hydrogen roomsSemiconductor fabs
ShareLinkedInEmailWhatsAppX
Key dates
21 Aug 2018
Directive 2017/164 transposed (4th IOELV list)
20 May 2021
Directive 2019/1831 transposed (5th IOELV list)
30 Jun 2003
ATEX workplace Directive 1999/92/EC applies to new workplaces
20 Apr 2016
ATEX equipment Directive 2014/34/EU applies
What the rule requires

Article references are to the text in the Official Journal; summaries are informational, not legal advice.

Indicative OELVs → national limitsMember States set national limits taking the EU indicative values into account: e.g. CO 20 ppm (8 h) / 100 ppm (15 min), SO₂ 0,5 / 1 ppm, NO₂ 0,5 / 1 ppm (2017/164); NH₃ 20 / 50 ppm (2000/39). Check the national value (NL: Arboregeling bijlage XIII; DE: TRGS 900).
Explosion protection document — 1999/92/EC Art. 8Employer classifies hazardous areas into zones 0/1/2 (gas) and documents the risk assessment and measures.
Equipment in zones — 2014/34/EUEquipment groups/categories (II 1G, 2G, 3G) matched to zones; harmonised standards give presumption of conformity.
Gas detector performance — EN 60079-29-1Combustible-gas detectors: performance requirements (response, accuracy, drift) for detectors used for %LEL safety functions; EN 60079-29-2 covers selection, installation and maintenance.
Calibration & recordsDetectors used for safety functions are calibrated at intervals defined by the manufacturer and the safety case; records are inspected.
What you have to measure
  • Toxic gases at the OEL: CO, NH₃, SO₂, SO₂F₂, CH₃Br (ppm) — fixed detectors near sources and in confined spaces
  • Combustible gases in %LEL: CH₄, C₃H₈, hydrocarbons, H₂ (non-NDIR) — zoned areas
  • Oxygen deficiency (asphyxiants CO₂, SF₆, N₂) — electrochemical O₂ plus NDIR for the displacing gas
  • Fumigation clearance: SO₂F₂ and CH₃Br below re-entry limits
// Exposure above national limits and missing zone classification are labour-inspection findings with fines; explosion-protection failures are criminal liability in most Member States.
Tremon products for this rule
Questions engineers ask
NDIR or catalytic for %LEL?
NDIR for hydrocarbons in oxygen-poor or sulphur-laden atmospheres (no poisoning, no O₂ needed); catalytic where hydrogen must be covered (H₂ has no IR absorption).
Which document lists the Dutch limits?
Arboregeling bijlage XIII (wettelijke grenswaarden); the SER database publishes them online.
Get a quote

Tell us what you measure — just tap

Three taps and an email. An engineer replies within 24 h with feasibility and a price indication.

1 · Which gas?
2 · What for?
3 · What form?
4 · Where do we reply?
Goes to sales@tremon.nl. No newsletter, no tracking.
Other regulations
Sources
  1. Directive (EU) 2017/164, OJ L 27, 1.2.2017 — Annex values for CO, SO₂, NO₂; Directive (EU) 2019/1831, OJ L 279, 31.10.2019; texts saved 2026-09-17
  2. Directive 1999/92/EC (Art. 4, 7, 8, Annex I zones); Directive 2014/34/EU (Annex I categories); texts saved 2026-09-17
  3. IEC/EN 60079-29-1 and -2 (webstore.iec.ch abstracts, opened 2026-09-17)
// Read from the Official Journal texts on 2026-09-17. Regulations change — verify the current consolidated text before acting.
Get a quote →