Confined Spaces Hazards in Construction — Controls and RAMS Guidance
TL;DR
Confined Spaces is a significant hazard on UK construction sites. Proper risk assessment, written controls in the RAMS, worker briefing and ongoing supervision are all required by law. Failures in this area are among the most commonly cited in HSE enforcement action.
Who Is at Risk
Workers carrying out activities involving confined spaces are at direct risk. Others in the vicinity — nearby trades, supervisors, visitors and members of the public — may also be affected by the hazard. Risk assessment must consider all people who may be affected, not just those directly carrying out the work.
Legal Framework
The Health and Safety at Work Act 1974 requires employers to ensure the health, safety and welfare of their employees and others affected by their work. The Management of Health and Safety at Work Regulations 1999 require a suitable and sufficient risk assessment. CDM 2015 requires that RAMS are prepared for significant risks and that workers are briefed before tasks begin.
Specific regulations may also apply depending on the nature of the hazard — including COSHH, MHOR, WAH Regulations, PUWER, LOLER and others.
Common Causes of Incidents
- Failure to identify the hazard before work starts
- Inadequate or generic risk assessment not tailored to the specific task
- Workers not briefed on the controls in the RAMS
- Supervision failing to monitor compliance with controls
- Conditions changing during the work without review of the RAMS
- Inadequate PPE or PPE not worn
Control Hierarchy
- Eliminate the hazard where reasonably practicable through design or process changes
- Substitute with a lower-risk alternative (different materials, methods or equipment)
- Engineering controls to reduce exposure at source (guarding, extraction, barriers)
- Administrative controls to reduce the time and frequency of exposure (permits, supervision, training)
- PPE as the last line of defence for residual risk
Controls must be applied in this order. Jumping straight to PPE without considering engineering controls is not compliant with the law.
RAMS Requirements
The RAMS for tasks involving confined spaces must include:
- Clear identification of the hazard and who is at risk
- Specific controls selected from the hierarchy above
- PPE specification with standards (EN numbers)
- Supervision and monitoring arrangements
- Emergency procedures in the event of an incident
- Any permits to work required (hot works, confined space, etc.)
- Briefing and sign-off requirements before work starts
Site Evidence Checklist
- Hazard-specific risk assessment completed and approved
- RAMS includes confined spaces controls
- All workers briefed on RAMS with signed attendance records
- Required PPE available, inspected and being worn
- Any required permits in place before work starts
- Supervision monitoring compliance throughout the task
- Incidents and near-misses recorded and reported
- Post-task review completed and documented
FAQs
Does a risk assessment for this hazard need to be task-specific?
Yes. Generic risk assessments that are not adapted to the specific task, location and workforce do not meet the requirement for a "suitable and sufficient" assessment under the MHSWR 1999. The assessment must reflect actual site conditions.
What if the task cannot be made safe with the controls available?
Stop the task. Escalate to the site manager or principal contractor. Do not proceed with an unsafe task. Document the concern in writing and seek further advice before resuming.
How often should the risk assessment be reviewed?
At least when significant conditions change, after any incident, and annually as a minimum. On dynamic construction sites, risk assessments should be reviewed far more frequently — before each distinct phase of the task.
Who is responsible for the risk assessment?
The employer of the workers carrying out the task is responsible for the risk assessment. In practice, supervisors and foremen prepare them, but the employer remains legally responsible for their adequacy.
Can we use a standard template from the internet?
A template is a starting point. Every risk assessment must be adapted to the specific hazard, task, site and workforce. Unadapted templates have no legal standing and may give a false impression of compliance.