Sulphuric Acid Plant Safety - Sulphur Trioxide
November 9, 2003

Introduction

Sulphur trioxide is considered a poison.  Inhalation of the vapours, swallowing the material of severe skin contact can result in death.   Skin and eye contact causes severe burns and blindness.

If a release of sulphur trioxide has occurred the following should be considered:

• Do not put yourself in danger by entering a contaminated area to rescue a victim
• Stay upwind and uphill
• For a container, vessel or tank containing sulphur trioxide exposed to fire there is a risk of explosion
• Evacuate the area immediately downwind of a release
• Avoid contacting the spilled liquid with water as it will react violently with water to form sulphuric acid.  If water must be used, use it in flooding quantities.

First Aid

Inhalation – Remove the victim to fresh air and give oxygen if available

Contact with Skin – Remove and isolate contaminated clothing (including shoes) and wash skin with soap and large volumes of water for a minimum of 15 minutes and then apply a clean dry dressing

Contact with Eyes – Rinse with large volumes of water or saline for a minimum of 15 minutes

Ingestion – Do not induce vomiting

In all cases of contact with sulphur trioxide medical assistance must be sought immediately.  Toxic effects may be delayed.

Safety Signs

From a transportation perspective, sulphur trioxide is classified as a poisonous gas and corrosive.  Any or all of the following signs maybe displayed in the presence of sulphur trioxide.