Confined Space RAMS Guide for UK Contractors

Key Topics in a Confined Space RAMS

Space classification

Not all enclosed spaces are confined spaces under the Regulations. A confined space is one that is substantially enclosed and where there is a reasonably foreseeable specified risk (oxygen deficiency or enrichment, flammable gas or vapour, free-flowing solid, liquid, fire, or explosion). The RAMS must record the classification assessment for each space entered.

Atmospheric testing

Before any person enters, the atmosphere must be tested for oxygen content (normal: 19.5–23.5%), flammable gas (below 10% LEL), and toxic gases or vapours relevant to the space (H²S, CO). Testing must be carried out with a calibrated, bump-tested multi-gas monitor by a competent person. Testing must continue during occupancy where conditions may change.

Permit to enter

A permit to enter (or permit to work in a confined space) must be issued before each entry. The permit records: space identification, hazards assessed, atmospheric test results, PPE and equipment required, persons entering, entry and exit times, and the rescue plan. The permit must be closed on exit. The RAMS must describe the permit process.

Top person and rescue plan

A trained top person must be stationed outside the confined space at all times during occupancy. The rescue plan must describe: what action the top person takes if contact is lost, what rescue equipment is on site (tripod, winch, harness, SCBA), the sequence of actions, and only then when to call 999. The rescue plan must not rely on emergency services as the first-line response — by the time they arrive, suspension trauma or asphyxiation may already be fatal.

Breathing apparatus

Where atmospheric conditions require SCBA or airline BA for entry, the RAMS must confirm that operatives are trained, BA is maintained and within service, and that the BA duration is sufficient for the task plus rescue. BA use adds significant complexity to rescue planning.