DSEAR - Dangerous Substances Explosive Atmospheres Regulations

WHAT IS A DSEAR ASSESSMENT?

The assessments identifies areas at risk from the formation of potentially explosive fuel/air mixes, involving substances such as solvents or dusts. Identified areas are marked and precautions identified to reduce the risk of the formation of explosive atmospheres and to minimise the consequences should an explosion occur.

 

All places of work are required to carry out an assessment, if only to identify that there is no explosion risk! A soup factory is not a place that would spring to mind as a potential explosion risk but powdered soup in a fine suspension over certain concentrations makes for a very explosive mix .

 

Although most companies may not have large potential explosion risk, there may be a localised risk that has not been considered - waste buckets containing empty open solvent cans, or oil soaked rags for example.

WHO DOES IT APPLY TO?

Absolutely everybody needs to have carried out the assessment, and re assessments need to be carried out if equipment, substances or processes change. For many companies the assessment is a simple examination and a report saying that there is no potential risk, or that the risk is not significant if certain remedial action is taken. For other companies, areas will have to be marked to indicate their explosion potential, equipment and power supplies will need to be compliant with particular levels of electrical safety etc.

WHY DO WE ASSESS?

To reduce the potential risk of an explosion injuring or killing someone or damaging equipment. A properly carried out assessment will identify changes that can reduce or eliminate risks, or where the risk of explosion cannot be reduced/eliminated suggest actions which will minimise the potential for an explosion and its consequences

WHAT SHOULD BE ASSESSED?

All processes that use chemicals or substances or procedures that can produce an explosive atmosphere need to be assessed. Much of the information needed for this is contained in the same data sheets used to carry out the COSHH assessment.

PREPARING FOR AN ASSESSMENT

Collection of information on the ignition temperatures and explosion properties of all of the chemicals, substances  that you have in store or us and the by products of your processes. Determination of room sizes. Examination of the types of equipment in use, including the level of electrical safety etc. and existing damage limitation measures; blast doors or panels, potential paths for explosive blasts and any other potentially relevant information such as potential risks from chemical mixing, localised minor explosions causing the potential for larger incidents etc.

CARRYING OUT ASSESSMENTS

The explosion limits for the chemicals along with quantities used/stored and room sizes are examined to see if there is the  potential for the formation of explosive mixtures (large scale or localised). Products are reviewed for risks of producing "fuel" for an explosion by spills or use or from the formation of by products, i.e. sawdust!. Potential risks from vapour build up etc. also need to be investigated. If a risk is identified then an explosive zone according to DSEAR has to be declared, signage displayed  and all electrical systems and appliances have to be met the appropriate safety standard or be changed, and any other remedial or preventative actions determined

COLLECTING AND USING THE RESULTS

The results are used to determine:

    changes required to the reduce risks,

    specification requirements for new equipment,

    requirements for changes to existing equipment etc.

 

For more information on DSEAR assessment