Dynamic Risk Assessment: What It Is and When to Use One

What Is a Dynamic Risk Assessment?

A dynamic risk assessment is the check a trained worker makes on the spot, when they arrive at a job and while they’re doing it. They look at what’s actually in front of them, decide whether the planned way of working is still safe, and change the plan or stop if it isn’t.

It exists because written assessments can’t foresee everything. A field engineer’s assessment can cover ladders and electrics, but it can’t know that today the customer’s dog is loose, the loft hatch is rotten and it’s started to rain. The person on site has to deal with that, quickly and sensibly.

The word “dynamic” just means the situation is changing. The assessment changes with it: it isn’t done once, it carries on until the job is finished.

Where Does the Term Come From?

The phrase is most closely linked with the UK fire and rescue service, where incident commanders have to make fast decisions at fires, crashes and rescues that nobody could plan in detail. HSE’s 2010 report on the management of health and safety in the fire and rescue service expects incident commanders to have a thorough knowledge of the dynamic risk assessment process, alongside the Generic Risk Assessments, which are written risk assessments for foreseeable incidents.

That pairing is the useful lesson for any employer. Even in the most fast-moving work there is, the on-the-spot judgement sits on top of written assessments, prepared in advance under the Management of Health and Safety at Work Regulations 1999, and on top of training. It never stands alone.

Since then, the term has spread well beyond the emergency services. You’ll now hear it in care, utilities, security, logistics and construction.

Does It Replace a Written Risk Assessment?

No. This is the most common misunderstanding, and it can land an employer in trouble. “Our people do dynamic risk assessments” is not an answer to “where’s your risk assessment?”

The legal duty is in regulation 3 of the 1999 Regulations: every employer must make a suitable and sufficient assessment of the risks, and record the significant findings if they employ five or more people. The HSE’s 5 steps to risk assessment explain how. That written assessment should already cover the foreseeable variations in the work: bad weather, aggressive customers, faulty equipment, working late.

The dynamic assessment is how your trained people apply it on the day. Think of the written assessment as the map and the dynamic one as looking out of the window. You need both. If your written record is out of date or missing, start with our free risk assessment template, then build the on-the-spot checks into it.

When Should You Use a Dynamic Risk Assessment?

Whenever people work where conditions can change and nobody is there to make the call for them. The HSE’s guidance on protecting lone workers lists many of these jobs. Typical examples:

• Lone workers in shops, petrol stations, warehouses or on night shifts, who may face a situation with nobody to help.
• Care workers visiting people at home. The person’s condition, the home and the people in it can be different every visit.
• Field engineers and maintenance staff in customers’ homes and premises, where access, electrics, asbestos-era buildings and other trades are unknowns.
• Security staff, who hold authority over the public and may need to judge when to step back rather than intervene.
• Delivery drivers and couriers, dealing with roads, weather, loading areas, steps and dogs at every drop.

Lone working gets its own detailed treatment in our guide to lone working risk assessment. The HSE is clear that there’s no need for a separate lone working assessment, but the risks of working alone must be in your general one.

How to Do a Dynamic Risk Assessment: A Simple Method

There’s no official, legally set method. The one below is a practical way of remembering what good people already do. Teach it, practise it with real scenarios from your work, and make sure it matches your written assessment.

1. Stop. Before you start, and whenever something changes, pause. Don’t let time pressure or a customer rush you into the job.
2. Look. What’s different from what you expected? Check the area, the equipment, the people present, the weather and your own state (tired, unwell, short of time).
3. Assess. What could go wrong, how likely is it, and how bad would it be? Are the controls in your written assessment and training still enough here?
4. Act. Choose one: carry on as planned; carry on with extra precautions; change the method; get help or wait for a second person; or stop and withdraw. If in doubt, stop.
5. Review. Keep watching as the job goes on. If things change again, go back to the start. Afterwards, report anything the written assessment didn’t cover.

The “assess” step is the same judgement of likelihood and severity you’d make in a written assessment, just quicker. If your team uses a scoring grid, our guide to the risk assessment matrix explains how it works, though nobody should be doing sums on a doorstep.

What If It Isn’t Safe to Continue?

The most important outcome of a dynamic risk assessment is sometimes the decision to walk away. The law backs this up. Regulation 8 of the 1999 Regulations requires employers to have procedures that enable people exposed to serious, imminent and unavoidable danger to stop work and go immediately to a place of safety.

Employees have their part to play too. Section 7 of the Health and Safety at Work etc. Act 1974 requires them to take reasonable care of themselves and others, and to co-operate with their employer on safety.

In practice, workers need three things to make that real: clear authority to stop, a reliable way to call for help, and a manager who backs the decision without arguing about the lost job. The HSE’s lone working guidance expects you to have systems to keep in touch with lone workers and respond to incidents.

Do You Need to Record a Dynamic Risk Assessment?

There’s no legal form for one, and most happen in a minute or two. Asking people to stop and write an essay mid-task defeats the point.

What you should record is the learning. If someone finds a hazard the written assessment missed, stops a job, or has a near miss, it needs reporting, recording and acting on. That feeds step 5 of the five steps: review the controls. Some employers add a short tick-box check to the job sheet or a mobile app, which also gives a useful record of what people are finding.

Training People to Do It Well

A dynamic risk assessment is only as good as the judgement of the person making it. Section 2 of the 1974 Act requires employers to provide the information, instruction, training and supervision needed to keep employees safe, so far as is reasonably practicable.

Good training for this covers how to recognise the hazards of the job, what the written assessment expects, how to weigh likelihood against severity, and when and how to stop. It works best with real scenarios from your own work. A new starter should never be left to make these calls alone until they’ve seen and practised them.

What to Do Next

This week:

1. Pick one job your people do alone or in changing conditions, and check your written risk assessment covers the foreseeable variations.
2. Write down, in plain words, when staff should stop and who they call.
3. Talk the stop, look, assess, act, review method through with the team, using a real example from the last month.
4. Make sure near misses and stopped jobs are reported and fed back into the written assessment.

If the people writing your assessments, or making these calls on the day, haven’t had any training, start there. Our online risk assessment training covers the HSE’s method from identifying hazards to reviewing controls, with a certificate on completion.