What Good Looks Like: Managing Lone Workers on Site

The problem with lone working on site

Lone working happens on almost every construction project — the plant operator finishing up after the crew has left, the engineer doing a morning walkround before anyone else arrives, the operative fixing a snag in an empty building. It's routine. And because it's routine, it often gets treated as low risk.

It isn't. Working alone removes the most basic safety net in construction: someone nearby who can raise the alarm if something goes wrong. No supervision, no colleague to notice a collapse, a fall, a medical emergency. By the time anyone realises there's a problem, the window for a quick rescue may already be closed.

This article covers what genuinely good lone worker management looks like — not just a box-ticking exercise, but a system that would actually protect someone.

What counts as lone working?

HSE defines lone workers as those who work by themselves without close or direct supervision. On construction sites that includes:

• Operatives working in a separate part of a large site where no one else is present
• Workers arriving early or staying late after the main crew has left
• Engineers, surveyors or safety managers doing solo site walks
• Subcontractors working in plant rooms, roof voids or isolated areas
• Security or watchmen on unmanned sites overnight

If someone gets hurt and no one else is close enough to help within a few minutes, they were effectively lone working — regardless of what the rota said.

What a proper lone worker risk assessment covers

A lone worker risk assessment isn't the same as a general site risk assessment. It needs to address the specific conditions of working without supervision. At minimum it should cover:

• The task itself — is it one that specifically requires two people? Some tasks (certain confined space entries, work involving heavy plant, operations with a high energy source) should never be done alone, full stop.
• The location — how remote is it? What's the mobile signal like? How quickly could emergency services reach the worker?
• The individual — are they experienced? Do they have a medical condition that increases risk? New starters and young workers should almost never be permitted to lone work.
• Time of day — risks increase after dark or outside normal site hours when site facilities and other personnel are absent.
• Environmental hazards — poor lighting, unstable structures, moving plant, extreme weather.

The check-in system: what good looks like

A check-in system is the operational heart of lone worker safety. It sounds simple, but most sites do it badly — or not at all.

What bad looks like: "Give us a bell if you need anything." No set intervals, no escalation plan, no one designated to monitor it.

What good looks like:

1. Set intervals before work starts — agree a specific check-in frequency based on the risk level. High-risk tasks (working at height alone, confined space approaches, working near live services) might need every 30 minutes. Lower-risk tasks could be every hour or two.
2. Name a monitor — someone specific is responsible for receiving check-ins and acting if they're missed. Not "the office" generally — one named person per shift.
3. Define the escalation — if a check-in is missed, what happens? A single missed call should trigger an immediate attempt at re-contact. Two missed calls should trigger a physical welfare check or emergency call. Write this down. Test that the lone worker knows it.
4. Log it — a simple written or digital log of check-in times provides evidence of compliance and creates an accurate timeline if an incident does occur.

Communication equipment: don't assume mobile is enough

Mobile coverage is patchy across the UK, and many construction sites — basements, remote rural sites, steel-framed structures — are notoriously bad for signal. Before approving lone working, physically check the signal in the specific location where the work will happen.

Where mobile is unreliable, consider:

• Two-way radios — reliable, simple, no network dependency
• Satellite-enabled personal alarms — useful for very remote sites
• Man-down devices — wearable alarms that trigger automatically if the wearer stops moving or falls, often with GPS location
• Buddy system — for particularly high-risk tasks, a second person working nearby (not necessarily doing the same job) may be the right answer

The communication method should be specified in the risk assessment and confirmed with the worker before they start — not assumed.

Tasks that should never be done alone

Some construction activities have absolute restrictions on lone working. These include:

• Confined space entry — Regulation 5(1) of the Confined Spaces Regulations 1997 requires a safe system of work, which for confined spaces practically always means an attendant or supervisor present outside. Lone entry into a confined space is almost never compliant.
• Work on or near live electrical systems — requires supervision and ready access to emergency first aid.
• Demolition work — structural instability makes lone working extremely high risk.
• Any task where the risk assessment identifies that rescue without assistance is not possible — if the worker couldn't summon help or self-rescue in the likely injury scenarios, they shouldn't be doing it alone.

Supervision of lone workers: the manager's responsibility

CDM 2015 places a duty on principal contractors to plan, manage and monitor construction work. That includes work carried out by lone operatives. "I didn't know they were working alone" is not a defence if the management system should have identified and controlled it.

In practice, this means:

• Lone working should be explicitly addressed in the Construction Phase Plan where relevant
• Supervisors should be briefed on which tasks and areas require lone worker controls
• Site inductions should cover lone working rules and who to contact
• Any near-miss or incident involving a lone worker should be reviewed — the check-in system should be the first thing scrutinised

What documentation you actually need

You don't need an enormous folder, but you do need a paper trail that demonstrates the risks were assessed and controls were in place. At minimum:

• A lone worker risk assessment (task and location specific)
• A record of the check-in schedule and nominated monitor
• Evidence the worker was briefed (a signed induction sheet or toolbox talk record is fine)
• A log of check-ins during the work period

If you're generating risk assessments from site photos and notes, SiteSafePro can turn a typed description of the lone working task into a structured risk assessment in seconds — useful when a subcontractor turns up wanting to start solo work and the paperwork isn't in place yet.

The one question worth asking

Before any lone working starts, ask this: if that person was injured right now and couldn't use their phone, how long before anyone found them — and would it be soon enough?

If you can't answer that confidently, the system isn't good enough yet.