Risk of MSA SavOx units catching fire if the wearer does not follow start up procedures
Health and Safety Executive - Safety alert
Specialised Industries Division – Mines Inspectorate
13 June 2012
Mines; Construction, Utilities & Docks
An MSA SavOx oxygen self rescuer caught fire after being worn in an underground emergency evacuation.
MSA SavOx oxygen self rescuer units have been sold for over a decade and are widely used in mines and civil tunnelling.
The unit contains a chemical canister and when the unit is worn the user's breathing triggers a chemical reaction which produces oxygen. A by-product of this chemical reaction is heat.
The SavOx units are fitted with a starter mechanism which is designed to provide immediate oxygen and boost the start up reaction when the units are operated in low temperatures. This starter mechanism should be initiated by stretching the flexible breathing tube prior to inserting the mouthpiece.
Following a large emission of gas in a 2000m long coal mine development (tunnel) workers donned their SavOx oxygen rescuers to evacuate the affected area.
On reaching fresh air they removed their rescuers and laid them on the floor. Approximately 10 minutes later one of the team picked up one of the used rescuers by the mouthpiece and a 'popping' sound was heard. The rescuer began smoking from around the exhale valve and then burst into flames. The flames were quickly extinguished and no persons were injured.
It appears that the wearer had not triggered the starter when he put on the rescuer and when the used rescuer was picked up by the breathing tube the starter was activated. The unit was already hot and this supply of additional oxygen led to the fire.
The incident does not appear to be an individual manufacturing defect and further investigation is being undertaken.
Relevant legal references:
- Health and Safety at Work etc Act (1974)
- Personal Protective Equipment at Work Regulations 1992, Regulation 9
- Escape and Rescue from Mines Regulations 1995, Regulation 10
Specialised Industries Division
HM Inspectorate of Mines
Tel: +44 (0) 114 291 2390 or see
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