What is DSEAR? – A Comprehensive Guide to DSEAR Regulations

Aug 04, 2023

Dec 14, 2021

What is DSEAR and Why is it Important?

The Dangerous Substances and Explosive Atmosphere Regulations 2002 , or DSEAR for short, were brought into force to require employers to review all potential risks to people (employees and others) whose safety may be at risk of fires and explosions caused by dangerous substances in the workplace.

What Are Dangerous Substances?

Under the legislation, the term dangerous substance is interpreted as:

  • A substance or preparation which may be explosive, flammable, highly flammable or oxidising
  • A substance or preparation that creates a workplace risk because of physicochemical or chemical properties due to its function, way of use or presence in the workplace
  • Dust in the form of fibrous materials, solid particles or other forms which could form explosive properties when mixed with air or explosive atmospheres

DSEAR Requirements For Employers

The Management of Health and Safety at Work Regulations 1999 made it a legal requirement for employers to effectively manage workplace risks to humans: DSEAR made such rules apply directly to dangerous substances.

By their very nature as dangerous substances, they should be treated with severe caution as the danger posed by fire or explosion can have catastrophic effects, causing death or a severe depletion to a person’s quality of life.

The HSE rules oblige employers to cover:

  • What dangerous substances are present in the workplace and the risks they may pose
  • Place controls to remove the risks or mitigate them if it is not possible to fully remove
  • Put measures in place to limit the effects of incidents involving the dangerous substances
  • Design protocols to tend to accidents, emergencies and incidents that involve the dangerous substances
  • Ensure all employees are competent in controlling or tackling the risks posed by the dangerous substances – this can be achieved through the provision of information, training and supervision
  • Locate and classify potentially explosive areas of the workplace and avoid installing or using ignition sources in said locations i.e hazardous area classifications

The purpose of a DSEAR assessment is to ensure that the working environment is as safe as reasonably practicable, to avoid harm to workers and other relevant people (e.g. members of the public or contactors) caused by dangerous substances.

Relevant History and Context of DSEAR Regulations

The DSEAR was introduced into UK law as an implementation of the EU’s ATEX Directives, to reduce the risk of serious injury or death caused by dangerous substances igniting and potentially exploding such as sawdust and hydrogen gas. On leaving the EU the UK has retained these requirements in UK regulations.

In 2015, amendments to DSEAR meant that it also covers hazards caused by gases under pressure, as well as substances that are corrosive to metals. The amendments were made to bring the regulation in line with the directly effective EU Chemical Agents Directive, which detailed that any such risks must be eliminated or reduced as far as reasonably practicable.

When Do DSEAR Regulations Apply?

DSEAR applies to all places of work where dangerous substances may be present, produced and/or used.

What Type of Activities Are Covered Under DSEAR?

Here are several examples covered under DSEAR:

  • Flammable goods in retail stores
  • Petrochemical site (onshore and offshore)
  • Chemicals – manufacturing, processing and storage/warehousing
  • Presence/use of flammable gasses
  • Hot work – welding, soldering – that include flammable materials
  • Work/processes that release natural flammable substances
  • Industries that handle/store dust wastage
  • Petrol storage for intended use as fuel

Ensuring DSEAR Compliance

Employers have duties to assess and eliminate/minimise risks from dangerous substances. To ensure that your workplace is DSEAR compliant you must:

Assess Workplace Risks/Risk Assessment

To be DSEAR compliant, you must first conduct a DSEAR Risk Assessment on the workplace risks that may be caused by dangerous substances, involving the identification and examination of:

  • Presence of dangerous substances
  • Activities of work which include said substances
  • All potential ways such substances could cause harm

The Risk Assessment is there to assist employers in planning precisely what is required to minimise the risk from the dangerous substances or eliminate them entirely.

If a workplace is found to have no risks or merely trivial risks, no further action is needed to be taken. However, if there is the potential for significant risk, the next steps are required to be fully compliant with DSEAR.

Record Keeping

Where a workplace has five or more employees, the employer must record all major findings of the risk assessment. The format of the records is not fixed but the content is determined by sources of best practice including the DSEAR ACOP and BS EN 60079-10-1:2021 Explosive atmospheres – Part 10-1: Classification of areas – Explosive gas atmospheres.

Eliminating/Minimising Risks

Should the employer discover any major risks of harm, advisable control measures must be put in place to minimise the risks from dangerous substances or eliminate them where possible. Where it is not possible to eliminate risks, careful management and control of the risks is advisable, as well as reducing the severity of any harmful event.

The regulations advise that substitution – a replacement of the dangerous substance – is an ideal method to eliminate the risk, where possible, though it may be difficult to implement.

Management of Risks and Control Measures

There will be circumstances where replacement or substitution of dangerous substances is not practicable, the DSEAR regulations stipulate control methodology set out in an order of priority:

  1. Reduce the number of dangerous substances to a minimum
  2. Minimise release of dangerous substances or avoid entirely
  3. Carefully manage the release of dangerous substances at the source
  4. Prevent all dangerous atmospheres
  5. Avoid ignition sources and conditions that promote ignition, such as exceeding temperature limits that may lead to danger
  6. Keep reacting substances apart

Measures of Mitigation

DSEAR also advises employers to implement mitigation measures. Each measure needs to be consistent with the prior risk assessment and appropriate to the work involved, including:

  • Draw up emergency plans, procedures and protocol
  • Providing appropriate protective clothing and equipment
  • Supply explosion relief of explosion suppression tools and equipment
  • Minimise the number of employees potentially at risk
  • Control measures to limit the spread of explosions and fires
  • Access to explosion and corrosion-resistant plant

All employees should be trained and briefed with the correct information as to behaviour and procedure related to an incident or emergency, as well as appropriate equipment to carry out emergency work safely.

Employee training and instructions must include:

  • Each dangerous substance present and the risks they pose, including safety data and relevant legislation
  • Results emerging from the prior risk assessment and details of the control measures that have been put in place, inclusive of the purpose and instructions on how to follow them

Procedures in Case of Emergency – Employee Safety Training

Training – including all relevant information and instructions – must be distributed to all employees wherever it is required to increase the likelihood of employee safety: the information and training distributed needs to be proportionate to the level of risk.

Employers Must Also Follow ATEX Requirements

Although DSEAR was introduced to UK law to implement ATEX, employers must also follow ATEX-specific requirements. There is an interrelation between DSEAR and ATEX implemented by the Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 1996. This regulation stipulates certain requirements and certifications for products designed for use within explosive environments that could not be removed or avoided.

Who Can Conduct a DSEAR Assessment?

The health and safety executive (HSE) have stipulated that a “competent” person must carry out a DSEAR risk assessment. There is no set definition of competence nor official/mandatory license required to practice as a competent person in DSEAR. The depth of competence shall be proportionate the risk and complexity of the application. You should ensure your competent person has a thorough knowledge and relevant experience to the application. This is particularly important where the consequences may affect many people or members of the public.

Get Started with Spiers Engineering Safety

If you wish to remove the headache of HSE compliance and assessment, contact the experts at Spiers, who can conduct all workplace DSEAR assessments and direct the development of subsequent process and internal protective measures.

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Is DSEAR a legal requirement in the UK?

DSEAR is a legal requirement obliging employers to assess workplace risks and risks of explosions with causation of dangerous substances within the workplace. DSEAR also covers the risks caused by gasses under pressure and substances that are corrosive to metal, as of June 2015.

What is the difference between DSEAR and ATEX?

DSEAR is a UK law that was introduced as an implementation of the European Union’s ATEX regulations.

What is a DSEAR zone?

A DSEAR zone is specified as any place where an explosive atmosphere can occur that may require precautions to be implemented to ensure the safety of workers.

Who can carry out DSEAR?

HSE have specified that a DSEAR risk assessment must be carried out by a competent person: a person with good knowledge of DSEAR and experience in high-risk industries is advisable. Spiers, with over two decades of industry experience can take care of this for you.

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