--- title: "Hydrogen cyanide (74-90-8): exposure limits and sampling" url: https://analyt-mtc.com/tools/hazard-search/hydrogen-cyanide-74-90-8/ lang: en alternates: en: https://analyt-mtc.com/tools/hazard-search/hydrogen-cyanide-74-90-8/ de: https://analyt-mtc.com/de/tools/gefahrstoffsuche/hydrogen-cyanide-74-90-8/ --- Hazard search # Hydrogen cyanide CAS number 74-90-8 Also known as HCN · Hydrocyanic acid · Hydrocyanic acid (hydrogen cyanide) · Hydrogen cyanide (cyanides) · Hydrogen cyanide (hydrocyanic acid) ## UK workplace exposure limits | Limit | Value | Applies to | | --- | --- | --- | | 8-hour TWA | 0.9 ppm | | | 8-hour TWA | 1 mg/m³ | | | 15-minute STEL | 4.5 ppm | | | 15-minute STEL | 5 mg/m³ | | ### Notations - Sk: can be absorbed through the skin ## Sampling methods | Method | Sampling | Medium | Analysis | Part numbers | | --- | --- | --- | --- | --- | | **MDHS 56/3** / Hydrogen Cyanide by ISE / [Method document (opens in a new tab)](https://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs56-3.pdf) | Active (pump) | Midget impinger with prefilter | ISE | [225-36-2](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-2) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) / [225-70A](https://analyt-mtc.com/catalog/product/haz-dust-7204-particulate-monitor/#part-225-70a) / [225-1911](https://analyt-mtc.com/catalog/product/mixed-cellulose-ester-membrane-filters/#part-225-1911) / [225-1930](https://analyt-mtc.com/catalog/product/mixed-cellulose-ester-membrane-filters/#part-225-1930) | | **MDHS 56/3** / Hydrogen cyanide by ISE / [Method document (opens in a new tab)](https://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs56-3.pdf) | Active (pump) | Midget impinger with prefilter | | 225-36-52 / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) / [225-70A](https://analyt-mtc.com/catalog/product/haz-dust-7204-particulate-monitor/#part-225-70a) / [225-19](https://analyt-mtc.com/catalog/product/mixed-cellulose-ester-membrane-filters/#part-225-19) | | **NIOSH 6010** / Hydrogen cyanide by VAS / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/6010.pdf) | Active (pump) | Soda lime tube (600/200mg) & glass fibre filter in cassette | VAS | [226-210](https://analyt-mtc.com/catalog/product/skc-specific-sorbent-tubes/#part-226-210) / [225-710](https://analyt-mtc.com/catalog/product/glass-fibre-depth-filters/#part-225-710) | | **NIOSH 6017** / Hydrogen cyanide by IC / [Method document (opens in a new tab)](http://www.cdc.gov/niosh/docs/2003-154/pdfs/6017.pdf) | Active (pump) | Soda lime tube (600/200mg) & glass fibre filter in cassette | IC/ELCM | [226-210](https://analyt-mtc.com/catalog/product/skc-specific-sorbent-tubes/#part-226-210) / [225-710](https://analyt-mtc.com/catalog/product/glass-fibre-depth-filters/#part-225-710) | | **NIOSH 7904** / Cyanides by ISE / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/7904.pdf) | Active (pump) | 0.8µm PVC filter with fritted midget impinger | ISE | 225-2705 / [225-2LF](https://analyt-mtc.com/catalog/product/sureseal-cassette-blanks/#part-225-2lf) / [225-36-2](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-2) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) / [225-1](https://analyt-mtc.com/catalog/product/aluminium-respirable-dust-cyclone/#part-225-1) / [225-17-32](https://analyt-mtc.com/catalog/product/ptfe-polytetrafluoroethylene-filters/#part-225-17-32) | | **OSHA 1015** / Hydrogen Cyanide by IC -ELCHIM / [Method document (opens in a new tab)](https://www.osha.gov/sites/default/files/methods/osha-1015.pdf) | Passive | Soda lime passive sampler | IC-ELCM | [590-400](https://analyt-mtc.com/catalog/product/skc-hydrogen-cyanide-passive-samplers/#part-590-400) | | **OSHA ID 120** | Active (pump) | | ISE | [225-3LF](https://analyt-mtc.com/catalog/product/aluminium-respirable-dust-cyclone/#part-225-3lf) / [225-36-2](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-2) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) / [225-5](https://analyt-mtc.com/catalog/product/disposable-parallel-particle-impactors/#part-225-5) / [225-2902](https://analyt-mtc.com/catalog/product/filter-supports/#part-225-2902) | | **OSHA ID-120** / Cyanide by ISE / [Method document (opens in a new tab)](https://www.osha.gov/sites/default/files/methods/osha-id120.pdf) | Active (pump) | 37mm MCE filter with midget impinger | | [225-5](https://analyt-mtc.com/catalog/product/disposable-parallel-particle-impactors/#part-225-5) / [225-2902](https://analyt-mtc.com/catalog/product/filter-supports/#part-225-2902) / [225-3LF](https://analyt-mtc.com/catalog/product/aluminium-respirable-dust-cyclone/#part-225-3lf) / [225-36-2](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-2) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) | | **Non-agency** / Hydrogen cyanide by Colorimetric analysis | Direct-reading | Gastec detector tube | | [810-12H](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-12h) / [810-12M](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-12m) / [810-12L](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-12l) / [810-12LL](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-12ll) | | **Non-agency** / Hydrogen cyanide by Colorimetric analysis | Passive | Gastec Dosi-tube | | [810-12D](https://analyt-mtc.com/catalog/product/gastec-passive-dosi-tubes/#part-gst-12d) | | **Non-agency** / VOCs by solvent desorption and GC-FID / [Method document (opens in a new tab)](https://www.skcltd.com/images/pdfs/VOC_Chek_575_Series-Selection_Guide.pdf) | Passive | Passive sampler | | [575-001](https://analyt-mtc.com/catalog/product/skc-organic-vapour-passive-samplers/#part-575-001) / [575-002](https://analyt-mtc.com/catalog/product/skc-organic-vapour-passive-samplers/#part-575-002) | | **Other** | Passive | | IC-ELCHIM | [590-400](https://analyt-mtc.com/catalog/product/skc-hydrogen-cyanide-passive-samplers/#part-590-400) | | **Other** | Passive | | DR | [810-12D](https://analyt-mtc.com/catalog/product/gastec-passive-dosi-tubes/#part-gst-12d) | Methods and limits as published by their agencies and summarised by SKC; check the current method and the limit that applies to you before sampling. Source: [SKC Ltd (UK), Hazard Search, used with SKC's permission (opens in a new tab)](https://www.skcltd.com/hazard-search.html); [SKC Inc. (USA), Sampling Guides, used with SKC's permission (opens in a new tab)](https://international.skcinc.com/sampling-guides/)