Confined space risk assessment template: decide before anyone enters
Direct answer. A confined-space risk assessment decides whether the proposed work needs entry at all, whether the place and activity fall within the Confined Spaces Regulations 1997, what can go wrong, and what safe system and rescue arrangements are required if entry cannot be avoided. It must reflect the actual space, process, substances, people and work, not a generic “tank entry” label. Use the blank worksheet below to structure that competent decision. It is not a completed safe-entry assessment, atmospheric-test certificate or entry authorisation. A separate entry permit template records the verification and issue decision immediately before the job when the organisation uses a permit system. HSE legislation; HSE Approved Code of Practice L101.
HSE describes a confined space as one that is enclosed or largely enclosed and has a reasonably foreseeable specified risk: fire, explosion, loss of consciousness, asphyxiation or drowning. It may be a small chamber or a large silo. An awkward place is not automatically a confined space under this definition; a large accessible place may be one if its conditions create a specified risk. The assessor must consider what the planned work can introduce, not just what the space contains while idle. HSE introduction.
First decide whether entry can be avoided
The hierarchy begins before choosing a monitor or harness. Can the team inspect by camera, clean from outside, alter a valve from a safe position, take a sample remotely or change the work design? Record why a workable alternative was or was not selected. If access can be avoided, a permit and rescue plan for entry are the wrong solution. The Confined Spaces Regulations say to avoid entry so far as reasonably practicable. If unavoidable, use a safe system and prepare adequate emergency arrangements before work starts. HSE confined-space legislation.
Assess the *operation*, not just the container. Opening and cleaning a tank can disturb sludge and release gas; welding can consume oxygen, create fumes or introduce ignition; draining or mixing can change the atmosphere or cause a sudden inflow. A chamber may be safe for one inspection but unsafe during solvent cleaning. If the work or connected plant changes, the assessment needs review rather than a copied signature from yesterday.
The competent assessor should involve the people who understand the site and process: operator, maintenance team, contractor, designer or specialist and the future entrants and rescue team. Obtain drawings, material information, isolation details, previous test records and incident history. Where a contractor works on another organisation’s plant, assign responsibility for sharing accurate process and service information. A contractor cannot assess an unknown line simply because the work order says “make safe”.
Copyable risk assessment worksheet
Complete every applicable field. This is a planning template; do not tick “yes” by default or insert a standard gas-test value. If critical information is missing, record a HOLD and obtain it before entry.
A. Identification and scope
| Field | Job-specific entry |
|---|---|
| Site, asset and exact access point | [insert] |
| Proposed work and tools/materials | [describe task and potential introduced hazards] |
| Assessor, employer and competent reviewer | [names, roles, dates] |
| Space owner / process controller | [name and contact] |
| Dates, expected duration and crew | [insert] |
| Current process state and adjacent operations | [including connected lines and automatic plant] |
| Drawings, SDS, previous records and related plans | [IDs, revisions and limitations] |
Entry avoidance decision: Can the task be performed from outside? [options assessed]. Selected approach and why: [insert]. If entry is avoided, identify any remaining hazards for the external task and close this form without treating it as an entry assessment.
B. Does the confined-space definition apply?
| Test | Evidence |
|---|---|
| Enclosed or largely enclosed? | [shape, opening, natural ventilation, access geometry] |
| Reasonably foreseeable specified risk? | [fire / explosion / loss of consciousness / asphyxiation / drowning, and how] |
| Risk present now or introduced by work? | [process residue, gases, welding, cleaning, displaced oxygen, inflow] |
| Other serious hazards even if definition is not met? | [fall, electricity, moving plant, heat, poor access, biological exposure] |
| Conclusion and competent reason | [confined space under 1997 Regulations? yes/no/uncertain] |
If uncertain, do not use “not a confined space” as a shortcut. Escalate to a competent specialist and apply precautions appropriate to the credible worst case while the classification is resolved. HSE’s L101 provides examples and the decision framework.
C. Hazard, consequence and control plan
| Hazard/source | Who may be harmed and how? | Evidence or test needed | Avoid/eliminate or control | Owner and stop trigger |
|---|---|---|---|---|
| Atmosphere: oxygen, toxic or flammable | [insert] | [substances, instrument, locations and test plan] | [isolation, cleaning, ventilation, monitoring, suitable breathing protection if needed] | [name / alarm or loss of control] |
| Inflow, flooding or engulfment | [insert] | [lines, drains, weather/process state] | [isolation, blocking, upstream control and verification] | [name / unexpected flow] |
| Mechanical or electrical energy | [insert] | [plant diagram and isolation proof] | [lockout, securing moving parts and test] | [name / state change] |
| Fire, explosion or hot work | [insert] | [substances and ignition sources] | [eliminate ignition, controls, related permit] | [name / atmosphere change] |
| Entry/exit, fall, heat or fatigue | [insert] | [opening dimensions, route, weather, duration] | [access system, staffing, rest and retrieval compatibility] | [name / impaired exit] |
| Task-specific chemical/biological exposure | [insert] | [SDS/process history] | [substitution, hygiene, containment and PPE] | [name / unknown material] |
Do not rely on PPE as the only control where isolation or elimination is possible. Record how each isolation will be proved, not merely who says a valve is shut. If air testing is necessary, specify appropriate calibrated/function-checked equipment, competent tester, sampling positions, timing and response to changing readings. This template gives no universal pass thresholds because the substances, equipment, atmosphere and work determine the acceptable criteria. The competent assessor must set and document them using appropriate standards and instrument instructions. HSE L101.
D. Safe system of work
Describe the actual sequence, with who does each step: [prepare space] → [isolate and verify] → [clean/purge/ventilate if applicable] → [test atmosphere] → [set access and communication] → [confirm rescue readiness] → [authorise entry] → [perform task under monitoring] → [exit and account for all persons] → [restore plant under handback].
Fill in these working conditions:
- Entrants and competence:
[roles, relevant training, suitability and supervision]. - Standby/attendant:
[position, line of communication, other duties prohibited while entry is live]. - Isolation evidence:
[lock/tag, line blank, test and controller]. - Atmospheric controls:
[pre-entry readings, continuous/repeated monitoring decision, ventilation failure response]. - Access and equipment:
[ladder, tripod, lighting, intrinsically safe equipment where relevant, inspection]. - Interface controls:
[other trades, nearby process, delivery, public route]. - Time and change limits:
[work window, breaks, weather/process conditions, trigger to reassess].
Where a permit system is used, the permit verifies these arrangements at the site and time of entry; it does not substitute for this assessment. N5-019’s permit form should be linked here only once both pages survive final owner reconciliation. HSE’s ACOP discusses safe systems, precautions, testing and communication in more detail. HSE L101.
E. Emergency and rescue assessment
Assess foreseeable emergencies including an entrant becoming unconscious, a fall, atmospheric change, equipment failure, fire, flooding or inability to climb out. For each, record how the alarm is raised, how the casualty is extracted, who acts, which equipment and respiratory protection are needed, how rescuers avoid becoming casualties, how first aid is provided and how external services are contacted. Verify space geometry: a retrieval system that cannot pass an unconscious person through the opening is not a plan.
| Rescue scenario | Trigger and alarm | On-site rescue method and equipment | People and competence | Check/rehearsal evidence |
|---|---|---|---|---|
[e.g. unconscious entrant] | [insert] | [insert] | [insert] | [insert] |
[e.g. inflow or loss of air] | [insert] | [insert] | [insert] | [insert] |
The Confined Spaces Regulations require suitable and sufficient rescue arrangements before anyone enters, whether the emergency arises from a specified confined-space risk or another cause. HSE says not to rely on public emergency services as the sole rescue plan. Check that rescuers and equipment are available for the entire entry window and that the attendant can initiate the plan. HSE L101, regulation 5 and ACOP.
F. Assessment decision and review
Decision: [avoid entry / entry may proceed only after listed controls and rescue are verified / DO NOT ENTER]. Open conditions and owners: [insert]. Assessment completed by / time: [insert]. Independent competent reviewer / time: [insert]. Workers consulted/briefed: [names and dates]. Review trigger: [change of task, plant, substance, atmosphere, crew, weather, access, incident or monitor alarm]. Related permit reference: [insert when issued].
Do not use a residual-risk colour as permission to enter. The controls must be capable of working and must be in place. If a contractor changes a cleaning chemical, a line is reopened or the space is left unattended, stop and revisit the assessment. Record old and new versions so the team can tell which controls governed each shift.
Worked scenario: inspecting a below-ground pump chamber
A maintenance team needs to identify a pump fault. It first checks whether telemetry, a camera or removal from above can answer the question. If physical entry is needed, it obtains process drawings and confirms connected inlets, electrical supply and the possibility of oxygen deficiency or harmful gas. A competent assessor specifies isolation, atmosphere sampling, ventilation, an attendant, communication and rescue appropriate to the depth and opening. The crew records how an incapacitated entrant can be recovered; “call the fire service” is not enough. The permit issuer later verifies the specified controls at the chamber before entry.
If an unexpected upstream valve opens, monitoring alarms or heavy rainfall could affect the chamber, the entrance team exits and the job pauses. A reading from earlier in the day does not make an altered space safe. This scenario illustrates the decision process; it is not a completed assessment for any real pump station.
Common mistakes
- Treating any enclosed room as a statutory confined space without the specified-risk test, or ruling out a large silo because it is spacious.
- Starting with gas-monitor numbers and never asking whether entry can be avoided.
- Assessing only the normal process state and ignoring cleaning, welding, agitation, isolation failure or inflow.
- Calling a single reading near the opening proof of a safe atmosphere throughout the space.
- Naming PPE without a credible isolation, ventilation, communication or rescue system.
- Planning rescue only after an incident, or assuming a colleague should enter unprotected to help.
- Filing the form away while work conditions, plant or personnel change.
For organisations comparing record and approval workflows, the Complys risk-assessment page is a possible commercial destination; verify the exact route and live features before integration. Ask the vendor to demonstrate how a competent reviewer can see the current assessment, related permit and rescue plan. Software does not determine whether entry is safe or supply trained rescuers.
Source and claim register — checked 5 October 2026
| Claim | Primary source | Scope |
|---|---|---|
| Definition requires enclosed/largely enclosed space and reasonably foreseeable specified risk | HSE introduction | Great Britain guidance; task-specific assessment. |
| Avoid entry, use safe system if unavoidable, prepare rescue before work | HSE legislation | Confined Spaces Regulations 1997. |
| Detailed risk assessment, testing, precautions and rescue planning | HSE L101 ACOP | Assess actual space and task; do not copy generic thresholds. |
| Rescue plan cannot rely solely on public emergency services | HSE L101 regulation 5/ACOP | Rescue people/equipment matched to hazards and geometry. |
Complys helps you keep this organised and current. See Risk Assessment Software; confirm current capabilities for your use before relying on any specific feature.