A confined space is one which is both enclosed, or largely enclosed, and which also has a reasonably foreseeable risk to workers of fire, explosion, loss of consciousness, asphyxiation or drowning.
It may be small and restrictive for the worker like pipes or tanks or it could be far larger such as a grain storage silo with hundreds of cubic metre capacity.
What are the hazards?
Working in a confined space is dangerous because of the risks from noxious fumes, reduced oxygen levels, or a risk of fire.
Other dangers may include flooding/drowning or asphyxiation from some other source such as dust, grain or other contaminant.
What should employers do?
Wherever possible, they should avoid carrying out tasks in confined spaces. Where this is not possible, they must assess the risks of the particular confined space and plan how they will control those risks.
- if a confined space has noxious fumes, they should consider how these can be ventilated or removed;
- if there is a risk of liquids or gases flooding in, they should establish whether the valves can be locked shut or forecast the weather when working in rainwater drainage pipes.
- if someone is going into a confined space and there is not enough oxygen to breathe properly, employers must provide breathing apparatus or ventilate the space to increase oxygen levels before entering.
Employers should have emergency arrangements where necessary. If someone is working in a confined space, they should think about the following:
- How will they know workers are okay and haven’t been overcome by fumes?
- How will they get them out if they are overcome? (It is not enough to rely on the emergency services.)
Dos and don’ts of working in confined spaces
- be aware of the risks that may occur within a confined space;
- make sure the person doing the work is capable and trained in both the work and the use of any emergency equipment.
- work in confined spaces unless it’s essential to do so;
- ignore the risks – just because a confined space is safe one day doesn’t mean it will always be;
- let others enter a confined space until you are sure it’s safe to do so.