Report: Safe storage of wood pellet and wood chip fuel

Key messages

Wood pellets and wood chip biofuel can produce dangerous (toxic) atmospheres in unventilated, enclosed spaces producing carbon monoxide and carbon dioxide, and depleting oxygen concentrations. Appropriate controls to control the potential risk are ventilation and restriction of access to unauthorised persons. The stores and their adjacent areas should be assessed to determine if they should be classed as confined spaces. Training and safe working procedures are required. An HSE Safety Notice has increased awareness of the hazard, particularly amongst operators of small wood pellet or wood chip boiler systems, but the application of controls recommended by HSE is not comprehensive. Users of stores frequently do not have written risk assessments or safe working procedures in place. There may therefore be a need for further guidance to be produced in this area.

Research aims and objectives

The aim of the work was to carry out the following:

  • obtain information on how wood pellets and wood chips are stored before use,
  • to ascertain how the build-up of carbon monoxide in storage is controlled,
  • to find out what health and safety information suppliers and users have with regard to the storage and use of wood pellets/chip,
  • to obtain data with regard to the levels of carbon monoxide and other relevant gases in wood pellet/chip storage areas, and
  • to produce a report that includes an initial view on best control practices and procedures for use within the industry. 

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