A gas engineer servicing a boiler in an empty rental. A maintenance sparky checking an alarm panel in a plant room after hours. A sole trader surveying a loft on a domestic job. Lone working is everywhere in construction and M&E — and most of the time it passes without incident. But when something goes wrong and there's nobody there to help, a routine slip, a collapse or a medical emergency can turn into a fatality.
There's no law banning lone working in the UK. What the law does require is that you've assessed the risks and put sensible controls in place. This guide covers when a lone working risk assessment is needed, what it should include, and the practical measures that actually work on site.
What counts as lone working?
The HSE defines a lone worker as anyone who works by themselves without close or direct supervision. That's broader than people realise. It includes:
- Operatives on an empty or out-of-hours site with nobody else present
- Engineers visiting domestic properties or void units alone
- Maintenance staff covering a building on a night or weekend shift
- Sole traders working on their own across most of their jobs
- Anyone who is physically separated from colleagues even on a busy site (a worker in a plant room, riser or roof void while the rest of the gang is elsewhere)
The common thread isn't being the only person on a project — it's not having anyone close enough to notice and respond if things go wrong.
Do you legally need a lone working risk assessment?
Under the Management of Health and Safety at Work Regulations 1999, every employer must carry out a suitable and sufficient assessment of the risks their workers face. Lone working doesn't get a special exemption — if your people work alone, the risks of doing so form part of that assessment. If there are five or more employees, the significant findings must be written down.
Sole traders aren't off the hook either. The Health and Safety at Work etc. Act 1974 places duties on the self-employed where their work can create a risk to themselves or others. A written lone working assessment is also increasingly asked for by principal contractors and letting agents before they'll let you on site.
If you're unsure whether your activity needs a written assessment at all, our guide on whether you legally need a risk assessment walks through the test in plain English.
What a lone working risk assessment should cover
A lone working assessment doesn't replace your task-specific risk assessments — it sits alongside them and focuses on the fact that nobody is there to help. Work through these areas:
- The task itself. Is the work high-risk when done alone? Working at height, confined spaces, live electrical work, hot works and manual handling all become more dangerous without a second person. Some tasks should never be done solo.
- The person. Are they trained, competent and medically fit to work alone? New starters, young persons and anyone with a relevant health condition may need extra controls or should not work alone at all.
- The location. Remote sites, empty properties, poor mobile signal, difficult access for emergency services and unfamiliar buildings all raise the stakes.
- Communication. How will the worker stay in contact, and how often? What happens if they miss a check-in?
- Emergency response. If they're injured or taken ill, how quickly will someone notice, and how will help reach them?
- Violence and aggression. On domestic calls and void properties, the risk from members of the public or trespassers is real and often overlooked.
The structure is the same as any other assessment — identify hazards, decide who could be harmed, evaluate existing controls, and add more where needed. If you need a refresher on that framework, see the difference between a method statement and a risk assessment.
Practical controls that work
Controls only count if people actually use them. The ones that hold up on site are:
- A check-in system. Agree a schedule — a call or message on arrival, at set intervals, and on leaving. Make sure someone is responsible for raising the alarm if a check-in is missed.
- Lone worker devices or apps. Man-down alarms, GPS trackers and panic buttons are useful for high-risk or remote work. A phone with a charged battery is the minimum.
- Task restrictions. Ban the highest-risk work from being done alone — no live working, no confined space entry, no work at height on a fragile roof without a second person and proper planning.
- Dynamic risk assessment. Train workers to stop and reassess if the situation changes — unexpected aggression, a service that wasn't isolated, access that isn't what was expected.
- Clear escalation. Everyone needs to know who to call and when, and that supervisor needs to actually act on a missed check-in.
- A proper handover and induction. Even a lone worker should be recorded as being on site. Good site induction records and sign-in systems mean someone knows who is where.
Back up your assessment with a toolbox talk so the controls are understood rather than filed away. A short briefing on lone working, check-in procedures and what to do in an emergency takes ten minutes and sticks far better than a signature on a form. Our toolbox talks library has ready-to-deliver briefings you can run before a solo shift.
Common mistakes
- Treating lone working as "low risk" by default when the real issue is the absence of help, not the task.
- Relying on a worker's own phone with no agreed check-in and nobody watching for a missed call.
- Letting high-risk tasks drift into solo working because the job was quoted that way.
- Forgetting violence and aggression on domestic and void property visits.
- Writing the assessment once and never reviewing it when sites, teams or jobs change.
Frequently asked questions
Is lone working illegal in the UK?
No. Lone working is legal, but you must assess the risks and put appropriate controls in place. Certain high-risk tasks should not be done alone.
Does a sole trader need a lone working risk assessment?
If your work could put you or others at risk, you have duties under the Health and Safety at Work Act. A written lone working assessment is also commonly requested by principal contractors and clients before you start.
What tasks should never be done alone?
As a rule, confined space entry, live electrical work, certain work at height and anything requiring a second person for rescue or standby should not be carried out by a lone worker.
How often should I review a lone working assessment?
Review it whenever the task, person, site or equipment changes, after any near miss or incident, and periodically as part of your normal review cycle.
Do I need a special app or device?
Not always. For lower-risk work a reliable check-in routine and a charged phone may be enough. For remote or higher-risk work, a lone worker device with a man-down alarm or panic button is worth the investment.
Get the right documents in place
Lone working is one of those risks that's invisible until it isn't. A clear, written assessment and a check-in routine that people actually follow are what stand between a near miss and a tragedy.
SafetyPod's editable templates are written by a NEBOSH-qualified professional and drafted to current UK legislation. Start with the Risk Assessments library, grab the whole Risk Assessment Library bundle for 58 task-specific assessments, or go unlimited with SafetyPod membership at £69/year. Templates support competent people — they don't replace them, but they'll save you hours.