---
title: "Sulphur dioxide (7446-09-5): exposure limits and sampling"
url: https://analyt-mtc.com/tools/hazard-search/sulphur-dioxide-7446-09-5/
lang: en
alternates:
  en: https://analyt-mtc.com/tools/hazard-search/sulphur-dioxide-7446-09-5/
  de: https://analyt-mtc.com/de/tools/gefahrstoffsuche/sulphur-dioxide-7446-09-5/
---

Hazard search

# Sulphur dioxide

CAS number

7446-09-5

Also known as

SO2 · Sulphur oxide · Sulphurous anhydride · Sulphurous oxide

## UK workplace exposure limits

| Limit | Value | Applies to |
| --- | --- | --- |
| 8-hour TWA | 0.5 ppm |  |
| 8-hour TWA | 1.3 mg/m³ |  |
| 15-minute STEL | 1 ppm |  |
| 15-minute STEL | 2.7 mg/m³ |  |

## Sampling methods

| Method | Sampling | Medium | Analysis | Part numbers |
| --- | --- | --- | --- | --- |
| **NIOSH 6004** / Sulphur dioxide by IC / [Method document (opens in a new tab)](http://www.cdc.gov/niosh/docs/2003-154/pdfs/6004.pdf) | Active (pump) | Coated MCE filter in cassette | IC | [225-9005](https://analyt-mtc.com/catalog/product/skc-coated-treated-filters/#part-225-9005) / [225-1](https://analyt-mtc.com/catalog/product/aluminium-respirable-dust-cyclone/#part-225-1) |
| **OSHA 1011** / Sulphur dioxide by IC / [Method document (opens in a new tab)](https://www.osha.gov/sites/default/files/methods/osha-1011.pdf) | Active (pump) | Coated silica gel tube with glass fibre filter | IC | [226-177](https://analyt-mtc.com/catalog/product/skc-silica-gel-sorbent-tubes/#part-226-177) |
| **Non-agency** / Hydrogen sulphide + sulphur dioxide by Colorimetric analysis | Direct-reading | Gastec Detector Tube |  | [810-45H](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-45h) |
| **Non-agency** / Sulphur dioxide by Colorimetric analysis | Direct-reading | Gastec detector tube |  | 810-5 / [810-45S](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-45s) / [810-80](https://analyt-mtc.com/catalog/product/gastec-colour-gas-detector-tubes/#part-gst-80) |
| **Non-agency** / Sulphur dioxide by Colorimetric analysis | Passive | Gastec Dosi-tube |  | [810-5D](https://analyt-mtc.com/catalog/product/gastec-passive-dosi-tubes/#part-gst-5d) / [810-5DH](https://analyt-mtc.com/catalog/product/gastec-passive-dosi-tubes/#part-gst-5dh) |
| **Non-agency** / Sulphur dioxide by IC | Passive | UMEx 200 Passive Sampler |  | [500-200](https://analyt-mtc.com/catalog/product/skc-umex-200-passive-sampler-so2-no2/#part-500-200) |
| **Other** | Passive |  | IC | [500-200](https://analyt-mtc.com/catalog/product/skc-umex-200-passive-sampler-so2-no2/#part-500-200) |
| **Other** | Passive |  | DR | [810-5D](https://analyt-mtc.com/catalog/product/gastec-passive-dosi-tubes/#part-gst-5d) / [810-5DH](https://analyt-mtc.com/catalog/product/gastec-passive-dosi-tubes/#part-gst-5dh) |

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/)