Achieve DSEAR Compliance and Strengthen Workplace Safety, Faster

DSEAR is, in effect, a risk assessment. As part of these assessments of risks, DSEAR requires that a hazard must be present – this is usually the presence of an explosive atmosphere and an effective source of ignition.

The key requirements for complying with the regulations revolve around the completion of a thorough risk assessment and the undertaking of a Hazardous Area Classification (HAC).

Ultimately, the assessment aims to provide a coherent focus for the identification and mitigation from:

• flammable substances with explosive and oxidising properties alongside substances corrosive to metal
• substances that can create explosive atmospheres
• work activities involving other substances that could create a fire, explosion or similar energetic (energy releasing) event e.g. runaway exothermic reactions, decomposition of unstable substances, dust explosions.
• the occurrence of industrial incidents caused by fires and explosions

Dangerous substances include a wide variety of materials present in the workplace that can be classified as flammable, explosive or corrosive to metals. This can include gases, mists, vapours and other combustible materials such as dust and powders.

Examples of potentially dangerous substances found at work include: 

• bulk powders

• chemical manufacturing by-products

• paints and flammable solvents

• flammable gases

• flammable liquids

• dust from machining and sanding operations

• dust from foodstuffs

• pressurised gases

• flammable propellants

• flammable wastes including waste dusts

• liquid petroleum gas (LPG)

We offer testing services for a variety of potentially flammable substances and other chemicals including combustible dust & powder testing, flammable gases & vapour testing and electrostatic testing.

The testing of these dangerous substances will aid in characterising, preventing, protecting and mitigating workplace hazards to help you comply with DSEAR regulations.

DSEAR defines hazardous zones as a place where a potentially explosive atmospheres may or may not occur.

By defining an explosive atmosphere as a hazardous zone, special safeguards can be created in order to protect businesses, equipment, people, workplace and the environment.

A Hazardous Area Classification is used to identify risks in the places and areas of operation whereby control measures must be put in place i.e. intrinsically safe electrical equipment that conforms with the ATEX equipment directive (if necessary).

These classifications make up an integral part of the DSEAR risk assessment and is required by law – see DSEAR Regulation 7. 

Dangerous substances, as defined by DSEAR, is any substance in the workplace that could, if not properly controlled, lead to potential hazards when present in explosive atmospheres.

Compliance with DSEAR regulations, therefore, requires that the risks posed by such dangerous substances be removed or controlled to protect people from explosions and fire.

You will need a DSEAR if you deal with dangerous substances in the workplace. 

Take a our 2 minute DSEAR Quiz here. 

A DSEAR assessment should always be reviewed if you believe your current DSEAR may be invalid.

Although this could include the standardised 3-5 year time frame, it is recommended that a risk assessment review should occur if you have recently had a near miss or if you have made a minor change to your process.

The cost of a DSEAR assessment with Sigma-HSE will range depending on factors such as: 

• Size of plant or facility
• Type of DSEAR assessment (i.e., Review/Desktop/On-Site)
• Specific compliance needs
• Nature of your hazardous materials

You can get a free quote by filling in a form. Our team will get back to you asking for a couple of details and you will receive a quote in just a few days.

Each assessment targets different workplace hazards under specific regulatory frameworks.
A DSEAR (Dangerous Substances and Explosive Atmospheres Regulations) assessment focuses exclusively on identifying and mitigating risks related to flammable substances, explosive atmospheres, and potential ignition sources.

In contrast, COSHH (Control of Substances Hazardous to Health) assessments are concerned with the health effects of hazardous substances—like dusts, fumes, or chemicals—on workers. Fire Risk Assessments under the Regulatory Reform (Fire Safety) Order are broader, addressing general fire safety risks across premises, regardless of whether flammable substances are present.

At Sigma-HSE, we help clients navigate these overlapping but distinct regulatory obligations, ensuring each risk area is robustly covered and fully compliant.

The DSEAR Regulations require assessments to be carried out by someone with sufficient knowledge, training, and experience in managing explosive atmospheres and dangerous substances.

A competent person should understand not only the chemical and physical behaviour of hazardous substances but also be familiar with relevant engineering controls, protective systems, and regulatory compliance.

Sigma-HSE’s consultants are chartered professionals and sector specialists with years of experience delivering DSEAR compliance across high-risk industries. Our team ensures that your risk assessment stands up to regulatory scrutiny and is grounded in best practice.

Yes. While DSEAR is a regulatory requirement, it can and should be integrated with broader process safety methodologies.

At Sigma-HSE, we regularly align DSEAR assessments with HAZID (Hazard Identification), HAZOP (Hazard and Operability Study) and QRA (Quantitative Risk Assessment) techniques. This ensures a holistic view of potential risks across both routine operations and abnormal scenarios.

Our cross-disciplinary approach helps streamline compliance, prevent duplication of effort, and strengthen your organisation’s overall safety performance.

Although each site and set of unit operations will never be the same, we follow a structured methodology to ensure DSEAR compliance:

1. Identification of Dangerous Substances
   Pinpoint all flammable gases, vapours, mists, and dusts used or generated onsite.

2. Assessment of Explosion and Fire Risks
   Evaluate the likelihood of explosive atmospheres forming and the presence of ignition sources.

3. Implementation of Control Measures
   Recommend suitable controls such as ventilation, inerting, zoning, and use of ATEX-rated equipment.

4. Documentation and Reporting
   Provide a detailed report including zoning classifications, equipment inventories, and risk mitigation strategies.

5. Review and Ongoing Monitoring
   Ensure regular updates to the assessment in line with process changes, incidents, or new substances introduced.

At Sigma-HSE, we delivers each stage with technical rigour, so your assessment meets both legal requirements and best-practice expectations.