Confined space
An enclosed or substantially enclosed place where there is a reasonably foreseeable specified risk: lack of oxygen, toxic gas, fire, flooding or free-flowing solids.
The legal definition has two parts, and both are needed. The space must be enclosed or substantially enclosed: a tank, a chamber, a sewer, a duct, an excavation, a ceiling void, a plant room. And there must be a reasonably foreseeable specified risk arising from the space or the work in it: serious injury from fire or explosion, loss of consciousness from gas, fume, vapour or lack of oxygen, drowning, asphyxiation from free-flowing solids, or being unable to reach safety because of the conditions. A basement with good ventilation is not a confined space; a basement where a petrol generator is running is.
The regulations require that entry be avoided where the work can be done another way; where it cannot, a safe system of work (in practice a permit, gas testing, ventilation, a top person, communications and an entry log) and emergency arrangements that do not rely on the public emergency services arriving in time. Confined space deaths usually come in pairs: the entrant, and the colleague who went in after them. The rescue plan is the difference.
Where it comes from
- Confined Spaces Regulations 1997 regs.3, 4 and 5: avoid entry, safe system of work, emergency arrangements.
- HSE Approved Code of Practice L101 (Safe work in confined spaces).
Questions people ask
Is an excavation a confined space?
It can be. A deep trench with poor ventilation, near a sewer, a gas main or ground contaminated with hydrocarbons, or where an engine is running nearby, meets the definition. Assess each one.
What training do people need?
Competence for the level of risk: awareness for low-risk spaces, full entry and rescue training for high-risk ones, with certified equipment. City & Guilds and similar schemes grade the training by risk level. The top person needs training too.
Confined space, handled on a phone
SiteLynx puts the RAMS, permits, inspections, audits, plant checks and records behind every term in this glossary on the crew's phones, signed on site, with a PDF at the end. 14 days free, no card.
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