The U.K NO1 DSEAR Risk Assessment Specialists

Case Studies » A Torn Construction Limited

The challenge

A visit was made to Shed 26 biomass storage facility located St. Georges Dock, Port of Hull on 16th April 2015 to consider compliance in respect of the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR).

The extensive warehouse supplements existing biomass facilities associated with Associated British Ports at Hull and Immingham. Shed 26 forms only part of the buffer stock essential to maintain biomass supplies.

Shed 26 has been purpose-designed to avoid gross accumulation of combustible dust associated with storage of biomass wood pellets.

The solution provided

The site was approaching commissioning at time of survey and feedback indicated that arrangements were representative of expected operational strategy. While operations are not particularly complex, the dust component of biomass wood pellets is potentially a hazardous substance under DSEAR regulation.

Dusts have a large surface area compared to their mass and since burning will only occur at the surface of a solid or liquid where it reacts with oxygen, this causes dusts to be much more flammable than bulk materials. Increased surface area can be as much as 200 times that of solid material and allows the dust to burn much faster - and catch fire with much less energy as there is no heat loss via conduction to the bulk.

It was confirmed that minimal combustible dust accumulations are expected within the biomass storage facility and no significant airborne dust clouds are likely. However this cannot be ruled out entirely and disturbance of any accumulated dust deposits may lead to local concentration approaching LEL – and subsequent fire or explosion hazard. Any dust clouds may then be ignited by sparks from static, maintenance or lighting etc.

Key advice provide was that all extract ventilation systems used in a dusty environment must be well-maintained, include conductive ductwork and avoid dust redistribution or blockages in system - with explosion relief and spark detection as relevant.

A detailed report of the findings was provided and a number of improvement recommendations were identified. Hazardous zoning requirements were clearly identified.