Explosion Testing for dust, gases & vapours
© EHTL December 2018

DSEAR (Dangerous Substances and Explosive

Atmospheres Regulations 2002)

All sites handling significant quantities of flammable dusts or powders capable of forming a potentially explosive atmosphere come under the ATEX 1999/92/EC ‘Worker Protection’ Directive, which is implemented in the UK by means of the Dangerous Substances and Explosive Atmospheres Regulations (DSEAR). If the flammability of a material is not known, a classification test (EN 80079-20-2:2016 Explosive atmospheres Part 20-2: Material characteristics Combustible dusts test methods) must first be undertaken to assess its potential explosion hazard. A summary of the important requirements under the legislation is given below as an aid to those involved in demonstrating compliance with the law.

DSEAR regulation 5 requires risk assessments that identify:

the hazardous properties of the substance; information on safety provided by the supplier, including information contained in any relevant safety data sheet; the circumstances of the work including: - o the work processes and substances used and their possible interactions; o the amount of the substance involved; o where the work will involve more than one dangerous substance, the risk presented by such substances in combination; and o the arrangements for the safe handling, storage and transport of dangerous substances and of waste containing dangerous substances; activities, such as maintenance, where there is the potential for a high level of risk; the effect of measures which have been or will be taken pursuant to these Regulations; the likelihood that an explosive atmosphere will occur and its persistence; the likelihood that ignition sources, including electrostatic discharges, will be present and become active and effective; the scale of the anticipated effects of a fire or an explosion; any places which are or can be connected via openings to places in which explosive atmospheres may occur; and such additional safety information as the employer may need in order to complete the risk assessment.

DSEAR Regulation 6 requires employers to:

eliminate or reduce risk as far as is reasonably practicable flammable materials should be replaced with non-flammables where possible control risks and, if there remains a possible explosion risk, mitigate the effect of the explosion consider the following control measures in order of priority: o reduce quantities to a minimum o avoid releases o if releases occur, control at source o prevent the formation of an explosive atmosphere, including provision of ventilation o collect, contain and render safe any flammable releases o avoid ignition sources, adverse conditions; segregate incompatible substances Mitigation measures to include (as appropriate): o reduce number of employees exposed o avoid propagation of fires/explosions o provision of explosion pressure relief o provision of explosion suppression o provision of plant able to withstand explosion o provision of personal protective equipment (PPE) o safely handle, store and transport flammable materials o ensure risk-reduction measures are maintained o any other practical safety measures

DSEAR Regulation 7 requires:

Area classification of the site Zoned areas to contain suitably-protected equipment Where necessary, hazardous areas marked with a sign Verification of overall explosion safety before first use Provision of anti-static clothing

DSEAR Regulation 8 requires, for every significant hazard identified by a risk

assessment:

Procedures, information, warning systems, remedial actions, escape facilities are in place in case of accidents, incidents and emergencies Liaison with the emergency services Ensure situation is mitigated and restored after an incident, with access restricted to those who are rendering the area safe, who should have appropriate PPE and specialised safety equipment

DSEAR Regulation 9 requires:

Suitable and sufficient information, instruction and training on the appropriate precautions and actions to be taken by the employee in order to safeguard those at the workplace.  The names, risks, data sheets and any legislative provisions of hazardous materials should be made available at the workplace, along with the significant findings of any risk assessments.

DSEAR Regulation 10 requires:

The identification of pipes and containers, particularly those that are visible, to alert employees and others to the presence of a dangerous substance so that they can take the necessary precautions.  Identification can also help to avoid confusion over contents and thereby avoid incorrect mixing of contents.

DSEAR Regulation 11 requires:

The employer responsible for the workplace to co-ordinate the implementation of measures taken under DSEAR to protect employees and others at the workplace from risks from explosive atmospheres. Click below for a short guide to dust explosion testing and compliance with DSEAR.
Fires and explosions under DSEAR and ATEX
Explosion Testing
© EHTL December 2018

DSEAR (Dangerous

Substances and

Explosive Atmospheres

Regulations 2002)

All sites handling significant quantities of flammable dusts or powders capable of forming a potentially explosive atmosphere come under the ATEX 1999/92/EC ‘Worker Protection’ Directive, which is implemented in the UK by means of the Dangerous Substances and Explosive Atmospheres Regulations (DSEAR). If the flammability of a material is not known, a classification test (EN 80079-20-2:2016 Explosive atmospheres Part 20-2: Material characteristics Combustible dusts test methods) must first be undertaken to assess its potential explosion hazard. A summary of the important requirements under the legislation is given below as an aid to those involved in demonstrating compliance with the law.

DSEAR regulation 5 requires

risk assessments that

identify:

the hazardous properties of the substance; information on safety provided by the supplier, including information contained in any relevant safety data sheet; the circumstances of the work including: - o the work processes and substances used and their possible interactions; o the amount of the substance involved; o where the work will involve more than one dangerous substance, the risk presented by such substances in combination; and o the arrangements for the safe handling, storage and transport of dangerous substances and of waste containing dangerous substances; activities, such as maintenance, where there is the potential for a high level of risk; the effect of measures which have been or will be taken pursuant to these Regulations; the likelihood that an explosive atmosphere will occur and its persistence; the likelihood that ignition sources, including electrostatic discharges, will be present and become active and effective; the scale of the anticipated effects of a fire or an explosion; any places which are or can be connected via openings to places in which explosive atmospheres may occur; and such additional safety information as the employer may need in order to complete the risk assessment.

DSEAR Regulation 6 requires

employers to:

eliminate or reduce risk as far as is reasonably practicable flammable materials should be replaced with non-flammables where possible control risks and, if there remains a possible explosion risk, mitigate the effect of the explosion consider the following control measures in order of priority: o reduce quantities to a minimum o avoid releases o if releases occur, control at source o prevent the formation of an explosive atmosphere, including provision of ventilation o collect, contain and render safe any flammable releases o avoid ignition sources, adverse conditions; segregate incompatible substances Mitigation measures to include (as appropriate): o reduce number of employees exposed o avoid propagation of fires/explosions o provision of explosion pressure relief o provision of explosion suppression o provision of plant able to withstand explosion o provision of personal protective equipment (PPE) o safely handle, store and transport flammable materials o ensure risk-reduction measures are maintained o any other practical safety measures

DSEAR Regulation 7 requires:

Area classification of the site Zoned areas to contain suitably-protected equipment Where necessary, hazardous areas marked with a sign Verification of overall explosion safety before first use Provision of anti-static clothing

DSEAR Regulation 8 requires,

for every significant hazard

identified by a risk

assessment:

Procedures, information, warning systems, remedial actions, escape facilities are in place in case of accidents, incidents and emergencies Liaison with the emergency services Ensure situation is mitigated and restored after an incident, with access restricted to those who are rendering the area safe, who should have appropriate PPE and specialised safety equipment

DSEAR Regulation 9 requires:

Suitable and sufficient information, instruction and training on the appropriate precautions and actions to be taken by the employee in order to safeguard those at the workplace.  The names, risks, data sheets and any legislative provisions of hazardous materials should be made available at the workplace, along with the significant findings of any risk assessments.

DSEAR Regulation 10

requires:

The identification of pipes and containers, particularly those that are visible, to alert employees and others to the presence of a dangerous substance so that they can take the necessary precautions.  Identification can also help to avoid confusion over contents and thereby avoid incorrect mixing of contents.

DSEAR Regulation 11

requires:

The employer responsible for the workplace to co-ordinate the implementation of measures taken under DSEAR to protect employees and others at the workplace from risks from explosive atmospheres. Click below for a short guide to dust explosion testing and compliance with DSEAR.