Confined Spaces Regulations 1997: HSE Rules

Regulatory citation: Confined Spaces Regulations 1997 (SI 1997/1713)

What Are the Confined Spaces Regulations?

The Confined Spaces Regulations 1997 apply to work in confined spaces in Great Britain. A confined space is any place that is substantially enclosed, such as a chamber, tank, vat, silo, pit, trench, pipe, sewer, flue or well, where there is a reasonably foreseeable risk of serious injury from a specified risk. The specified risks are fire or explosion, loss of consciousness from rising body temperature, loss of consciousness or asphyxiation from gas, fume, vapor or lack of oxygen, drowning from a rising liquid level, and asphyxiation or entrapment by a free-flowing solid such as grain, flour, sugar or sand.

Why These Regulations Matter

Confined space hazards often can't be seen or smelled, and incidents often kill would-be rescuers too.

Core Requirements

1. Avoid Entry Where Possible (Regulation 4(1))

No one may enter a confined space to carry out work if it is reasonably practicable to do the work another way, for example from outside using remote cameras, long-handled tools or cleaning equipment.

2. Use a Safe System of Work (Regulation 4(2))

If entry is unavoidable, people may only enter, work in and leave the space under a system of work that makes it safe and without risks to health, based on an assessment of the specific space and task.

3. Put Emergency Arrangements in Place First (Regulation 5)

No one may enter or work in a confined space unless suitable and sufficient rescue arrangements are in place. They must reduce risks to rescuers so far as reasonably practicable and, where resuscitation is a likely consequence of a specified risk, include providing and maintaining resuscitation equipment. The arrangements must be put into action immediately when needed.

Elements of a Safe System of Work

• Supervision and competence: appoint a supervisor and make sure workers are trained, experienced and suitable for the work
• Isolation: mechanically and electrically isolate equipment, and isolate pipework that could let in gas, fume, vapor or liquid
• Cleaning and ventilation: remove residues before entry and provide fresh air, never using oxygen to sweeten the air
• Atmosphere testing: test for oxygen and toxic or flammable gases with a calibrated detector, with continuous monitoring where needed
• Equipment: use suitable tools, lighting and breathing apparatus where the air can't be made safe
• Communication and permits: keep contact with people outside, and use a permit-to-work to check all precautions are in place

Common Compliance Approaches

Follow ACOP L101

HSE's Approved Code of Practice and guidance, L101 Safe work in confined spaces, explains how to meet the regulations in practice.

Practice Rescues

Run rescue drills so on-site rescuers are trained, equipped and protected.

Example: Confined Spaces in Practice

A food manufacturer needs to clear a blockage in a flour silo. External methods fail, so entry is required. The supervisor isolates the feed conveyor, issues a permit and tests the atmosphere. The worker wears a harness with a lifeline to a winch outside, a trained standby person keeps watch with a radio, and rescue equipment is set up at the hatch before work starts.

Related regulations: Australian WHS confined spaces, OSHA Permit-Required Confined Spaces, MHSWR risk assessments.

Note: This summary reflects the regulations as they apply in Great Britain, enforced by the Health and Safety Executive (HSE) and local authorities. Northern Ireland has equivalent but separate legislation. Always check the current legislation and HSE guidance.

Frequently Asked Questions

What makes a space a confined space under the regulations?

A space must be substantially enclosed and have a reasonably foreseeable risk of serious injury from one of the specified risks, such as fire, explosion, toxic gas, lack of oxygen, drowning or entrapment in free-flowing solids.

Do the Confined Spaces Regulations require a permit-to-work?

The regulations require a safe system of work rather than naming a permit specifically. However, HSE guidance recommends a permit-to-work as a formal check that all elements of the safe system are in place before anyone enters.

Can we rely on the fire service for confined space rescue?

No. Rescue arrangements must be in place before entry, and HSE guidance is clear that relying on the emergency services is not enough. On-site rescuers should be trained, equipped and able to act quickly.