---
title: "Isocyanates: exposure limits and sampling — Analyt-MTC"
url: https://analyt-mtc.com/tools/hazard-search/isocyanates/
lang: en
alternates:
  en: https://analyt-mtc.com/tools/hazard-search/isocyanates/
  de: https://analyt-mtc.com/de/tools/gefahrstoffsuche/isocyanates/
---

Hazard search

# Isocyanates

CAS number

No CAS number

Also known as

Isocyanates (all) (as -NCO) · Isocyanates (see specific isocyanate) · See individual compounds

## UK workplace exposure limits

| Limit | Value | Applies to |
| --- | --- | --- |
| 8-hour TWA | 0.02 mg/m³ |  |
| 15-minute STEL | 0.07 mg/m³ |  |

### Notations

-   Sen: can cause sensitisation

## Sampling methods

| Method | Sampling | Medium | Analysis | Part numbers |
| --- | --- | --- | --- | --- |
| **MDHS 25/4** | Active (pump) |  | HPLC | [225-79A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-79a) / 225-9011 |
| **MDHS 25/4** / Organic isocyanates in air by HPLC -UV/EC / [Method document (opens in a new tab)](https://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs25-4.pdf) | Active (pump) | IOM Inhalable Sampler with Stainless Steel Cassette, GF/A 25 mm Filter impregnated with 1,2-MP (vapours) and Impinger (aerosols) in series |  | [225-76A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-76a) / [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) |
| **NIOSH 5521** / Isocyanates (monomeric) by HPLC -ECD/UV / [Method document (opens in a new tab)](http://www.cdc.gov/niosh/docs/2003-154/pdfs/5521.pdf) | Active (pump) | Midget impinger | HPLC-ELCHM & HPLC-UV | [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **NIOSH 5522** / Isocyanates by HPLC -FD/ECD / [Method document (opens in a new tab)](http://www.cdc.gov/niosh/docs/2003-154/pdfs/5522.pdf) | Active (pump) | Midget impinger | HPLC-FD | [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **NIOSH 5525** / Isocyanates, total (MAP) (Aerosols of aromatic isocyanates > 2µm)) by HPLC -UV/FD / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Impinger |  | [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **NIOSH 5525** / Isocyanates total (MAP) (Aerosols of aromatic isocyanates) by HPLC -UV/FD / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Impinger with coated glass fibre filter |  | [225-7](https://analyt-mtc.com/catalog/product/glass-fibre-depth-filters/#part-225-7) / [225-4](https://analyt-mtc.com/catalog/product/sureseal-cassette-blanks/#part-225-4) / [225-27](https://analyt-mtc.com/catalog/product/disposable-parallel-particle-impactors/#part-225-27) / [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **NIOSH 5525** / Isocyanates total (MAP) (Aerosols of aromatic isocyanates) by HPLC -UV / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Impinger with coated glass fibre filter |  | [225-7](https://analyt-mtc.com/catalog/product/glass-fibre-depth-filters/#part-225-7) / [225-4](https://analyt-mtc.com/catalog/product/sureseal-cassette-blanks/#part-225-4) / [225-27](https://analyt-mtc.com/catalog/product/disposable-parallel-particle-impactors/#part-225-27) / [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **NIOSH 5525** / Isocyanates,total (MAP) (Vapour only) by HPLC -UV/FD / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Stainless steel IOM with coated glass fibre filter |  | [225-79A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-79a) / [225-702](https://analyt-mtc.com/catalog/product/button-sampler/#part-225-702) |

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/)