Safety warning over wood pellets storage
Published: 15 November, 2012
LONDON: The Health and Safety Executive warns of risks of carbon monoxide poisoning in wood pellet storage areas. Since 2002 there have been at least nine fatalities in Europe caused by carbon monoxide poisoning in wood pellet storage areas including three deaths caused by entry into wood pellet storage facilities in domestic sites.
Wood pellets for boilers are normally stored in a large sealed hopper/tank or a storage room that has a screw feeder (auger) connected to the boiler. Alternatively, the hopper/tank can be mounted over the boiler for gravity feeding. Due to the enclosed nature of these hoppers/tanks/rooms, the atmosphere inside can become oxygen depleted and a toxic atmosphere containing carbon monoxide can accumulate.
The chemical reactions responsible for carbon monoxide production from wood pellets are assumed to be an auto-oxidation process, especially oxidation of the fatty acids to be found in wood.
The HSE advises all those who use, install, maintain or distribute wood pellet boilers and/or manufacture/store/distribute wood pellets to ensure correct installations of wood pellet hoppers/tanks/storage rooms and boilers and that no personnel should enter the hopper/tank unless fully trained and competent in confined space entry procedures.