Confined Spaces 

Section 4   Safety and Operational Procedures

4.7   

HIGH RISK CONFINED SPACES

4.7.1  

These are confined spaces where, in addition to the normal risks 

encountered, specific safety arrangements have to be undertaken to 

provide for safe working prior to entry and during occupation of the space. 

4.7.2 

Examples of High Risk confined spaces are set out in Annex E. 

4.7.3  

All work in High Risk confined spaces will be subject to a safe system of 

work and require a Permit to Work and Safety Method Statement. 

4.7.4  

Each High Risk confined space must be examined to identify the specific 

safety precautions necessary to ensure a safe system of work. 

4.7.5  

All High Risk confined spaces must have a notice fixed at all entry points. 

  Notices should be similar to the model safety signs illustrated in Annex 

F. 

4.7.6  

Unauthorised access to all High Risk confined spaces shall be restricted by 

either: 

n 

locks on access points 

n 

withdrawing access ladders 

n 

covers requiring proprietary keys. 

Access to keys to locks and covers is to be controlled by the duty 

Authorised Person. 

4.8   

SAFE WORKING PROCEDURES

General

4.8.1  

The precautions required in a safe system of work depend on the nature of 

the confined space and the risk assessment.  The main elements to be 

considered when designing safe working procedures are listed below.  

Further guidance is given by the Health and Safety Executive in Safe 

Working in Confined Spaces, Approved Code of Practice, Regulations and 

Guidance L101. 

Atmosphere Monitoring

4.8.2  

The atmosphere within a confined space may need testing for hazardous 

gas, fume or vapour or to check the concentration of oxygen prior to entry. 

4.8.3  

The exact testing, retesting and monitoring requirements should be 

determined from the risk assessments and be defined in the Safety Method 

Statement.  The appropriate choice of testing equipment will depend on 

particular circumstances and knowledge of possible contaminants. 

4.8.4  

Where a Permit to Work is to be issued, atmospheric checks must be 

carried out prior to entry into the confined space and continuously during 

occupation of the space. 

4.8.5  

The relevant section of the Permit to Work must be completed by the 

Person in Charge.  Atmospheric testing should be carried out on each 

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April 2005