Service
DSEAR Risk Assessments & Hazardous Environment Compliance
Practical DSEAR assessments for workshops, fuel installations, warehouses and commercial environments handling dangerous substances.
DSEAR Risk Assessments and Hazardous Environment Compliance
A DSEAR risk assessment is required under the Dangerous Substances and Explosive Atmospheres Regulations 2002 wherever flammable gases, vapours, liquids or combustible dusts could create a fire or explosion risk. Oak Tree Rule provides DSEAR risk assessments and coordinates specialist hazardous area and compliance services through competent delivery partners where required, ensuring assessments are undertaken by appropriately qualified professionals.
Reports are written to be used — by your engineers, your insurers and your enforcing authority — not filed and forgotten.
Why Oak Tree Rule?
Combining property, operational and compliance experience across large multi-site estates, Oak Tree Rule provides practical solutions focused on achieving compliance while maintaining operational efficiency.
Service
DSEAR Risk Assessments
Practical DSEAR assessments for workshops, fuel installations, warehouses and commercial environments handling dangerous substances.
Typical environments
- Vehicle workshops
- Fuel storage and dispensing areas
- Battery charging and EV infrastructure
- Warehouses
- Spray booths
- Plant rooms
- Manufacturing facilities
What we provide
DSEAR risk assessments
Full assessments to the 2002 Regulations and supporting ACOPs, written to be used — not filed and forgotten.
Hazardous area classification
ATEX zoning review (Zone 0/1/2 and 20/21/22) where required, with clear drawings and equipment suitability guidance.
Action plans & compliance
Prioritised action plans, compliance recommendations and ongoing portfolio support across multi-site estates.
How a DSEAR assessment runs
Structured to the 2002 Regulations and supporting ACOPs, with a deliverable that supports both insurers and the enforcing authority.
- 01
Substance & process review
Inventories, SDS, quantities, storage and process conditions reviewed off-site first.
- 02
Site walkdown
On-site review of plant, ventilation, ignition sources and existing controls.
- 03
Hazardous area classification
Zoning review with drawings and ATEX equipment suitability assessment where required.
- 04
Risk assessment & documentation
Full DSEAR risk assessment and written explosion protection documentation.
- 05
Action plan & recommendations
Prioritised actions, control measures and compliance recommendations.
Your assessment includes
A structured deliverable that covers identification, assessment and clear next steps.
Common questions
When is a DSEAR assessment legally required?
Whenever your work activity involves dangerous substances capable of causing harm from fire, explosion or similar energetic events — regardless of quantity. Even small amounts of solvents, LPG or combustible dust can trigger the duty.
How often should it be reviewed?
Reassess whenever processes, substances, quantities or the building change, and as a minimum every 2–3 years to keep zone classifications and control measures current.
Will you produce hazardous area classification drawings?
Yes — zoning drawings are issued as part of the assessment where relevant, covering Zone 0/1/2 for gases/vapours and Zone 20/21/22 for combustible dusts.
What is an Explosion Protection Document?
A written record required under DSEAR demonstrating that explosion risks have been identified, assessed and controlled. We produce this as part of the assessment deliverable.
Do you cover combustible dusts as well as flammable gases?
Yes — flour, sugar, wood, metal, plastic and chemical dusts are assessed against ATEX Zone 20/21/22 classifications alongside gases, vapours and mists.
Who needs DSEAR — only manufacturing sites?
No. Vehicle workshops, fuel storage and dispensing areas, fleet depots, warehouses, spray booths, battery charging facilities, plant rooms, manufacturing facilities and any site with flammable substances above screening thresholds all need a DSEAR assessment.
What's the penalty for non-compliance?
DSEAR is enforced by the HSE under HSWA 1974, with unlimited fines and potential custodial sentences for serious breaches. Insurers also typically require a current DSEAR assessment.
How does DSEAR interact with ATEX equipment regulations?
DSEAR (ATEX 153) covers the workplace duty; ATEX 114 / Equipment and Protective Systems Regs cover the equipment placed in hazardous areas. We review equipment suitability as part of the assessment.
Do you provide staff training?
Bespoke DSEAR awareness training for operators, maintenance teams and managers can be arranged through our delivery partners where required.
How long does a DSEAR assessment take?
Typical single-site assessments take 1–2 days on site with a draft report within 2–3 weeks. Multi-site or complex chemical processes are scoped individually.
Related services
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Free portfolio review
Send us your asset list and we'll come back with a no-obligation portfolio review — compliance gaps, savings opportunities and a prioritised action plan within one working day.
Get DSEAR-compliant with confidence
Tell us about your site and substances and we'll come back with a scoped quote within one working day.