Hazardous substances used in production or maintenance work can create significant risks. Product ranges change and contractors arrive on site. Temporary equipment is installed, and the overall fire and explosion risk can increase.
A Dangerous Substances and Explosive Atmospheres Regulations assessment captures how you control those hazards at a particular moment. Conditions on site start to change immediately afterwards as equipment is modified. Teams also adapt how they carry out tasks. An assessment that stays untouched while work changes will not satisfy regulators or protect people. Senior managers and safety leads need a clear view of how regularly to revisit the document, which events should prompt extra scrutiny and how to keep control measures aligned with current operations.
How a DSEAR Assessment Fits Into Your Risk Management Cycle
Under UK health and safety law, DSEAR is a specific duty that builds on the general risk assessment requirements in the Management of Health and Safety at Work Regulations. The assessment sets out where dangerous substances are present and how they are handled, explaining how ignition sources are controlled. It also records the basis of safety for how equipment is laid out and storage is arranged.
Once you have a complete assessment, it becomes the reference point for control measures, supporting decisions on maintenance, inspection and supervision. Planned review dates bring the assessment back into line and give regulators and insurers confidence that the written control strategy still matches how the site runs.
How Frequently Should a DSEAR Assessment be Updated?
Industry guidance and insurance requirements usually quote time-based intervals for DSEAR assessments. One common recommendation is to work on a three-year cycle for a stable, lower risk facility, with more frequent reviews for higher risk operations.
No fixed interval can cover every site. Risk profile and rate of change both matter. Any process that handles large quantities of flammable solvents or explosive dusts under a DSEAR assessment may justify shorter intervals, particularly where manual handling of containers, regular changeovers or frequent maintenance work take place. In contrast, a small, steady process with tight control of stocks may justify a longer interval, provided other triggers for review are built into local procedures.
Which Changes Cause a Fresh DSEAR Review?
Review decisions should never rely on the calendar alone. Workplace changes are central to a DSEAR assessment, and those changes act as early warning signs that the risk profile has changed.
Examples that normally prompt a focused review include:
- Introduction of new dangerous substances or changes in their concentrations
- Changes to mixing or filling processes, including new methods of spraying or cleaning
- Alterations to storage arrangements, such as different container sizes or revised stock levels
- Installation of new machinery or relocation of existing equipment
- Adjustments to ventilation or extraction
Each change can affect flammable atmospheres, escape routes and ignition sources. A fresh look at diagrams and hazardous area classification keeps a DSEAR assessment aligned. Where several changes occur over a short period, a full reassessment is usually the safest way to join up the effects.
How Previous Incidents Influence the Review Cycle
Near misses and incidents tell you how well control measures work under pressure. Flash fires, fume releases or uncontrolled spills show that the assumptions inside the original assessment may no longer hold.
Incident learning forms an important part of a DSEAR assessment. Repeated alarms linked to gas detection can prompt the same response. The review should explore where safeguarding measures worked and where they fell short. Follow-up actions can include improved equipment design and different cleaning methods. Revised work instructions or closer supervision may also be needed. An updated assessment then acts as the new reference point for future reviews.
What a DSEAR Review Checklist Should Cover
Structured checklists make review work more efficient and more consistent. It should test both the content of the assessment and the reality on the shop floor so that DSEAR assessment still reflects actual practice.
Typical checklist items include:
- Confirmation that the inventory of dangerous substances matches current use
- Review of where those substances are present in normal and abnormal conditions
- Checks that hazardous areas still match the conditions assumed in the assessment
- Verification that ignition sources remain controlled in each relevant location
Supporting information like drawings and operating procedures should match what the checklist finds, along with the associated records.
Who Holds Responsibility For Keeping DSEAR Assessments Current?
The legal duties under DSEAR assessment belong to the employer. In practice, multiple roles contribute to keeping assessments current. Clear division of responsibility helps avoid blind spots where process changes move ahead without any check against the original document.
Senior management sets expectations for review frequency and provides resources for the work. HSE advisers or competent external specialists lead the technical side of assessments and reviews. Line managers and supervisors ensure that safe systems for dangerous substances match the controls described in the assessment. Consistent communication between these groups keeps everyone focused on the same strategy.
Does Change Control Keep an Assessment Accurate?
Management of change procedures give another route to keep assessments current. Well-designed processes include prompts about dangerous substances whenever equipment or materials are altered, or when operating methods change.
Approval forms for process changes can include short questions about new or modified materials and about altered temperatures or pressures. Other questions can cover ventilation and containment. Where answers indicate a shift in fire or explosion risk, the form should direct the proposer to consult the DSEAR assessment or request a review. The habit prevents informal changes from eroding the protection that the original document describes and helps teams decide whether a focused or full reassessment is needed.
How Safety First Group Supports Ongoing DSEAR Compliance
In many organisations, internal teams have limited time to follow up every change and incident. External support can help you decide on a review interval that matches your risk profile and build the tools that make reassessment easier to carry out.
We review services and can deliver a DSEAR assessment, together with support on occupational hygiene and COSHH. Fire risk management support can be included where it fits your overall strategy. Our consultants work alongside your in-house teams to design a review strategy that matches your processes and site layout.
Need help planning or reviewing your current assessment? Contact us to arrange an initial discussion and explore options for on-site surveys.