Communication failure is a major cause of confined space accidents. Simple procedures can be put in place to prevent errors occurring before entry to a space takes place.
Establish a Dedicated Communication Link
The team should agree to use a single channel for communication between team members inside the confined space and the surface attendant(s). This could be a shared radio frequency and all team members should agree that communications on this frequency will only be for the purpose of the entry in progress.
Use Intrinsically Safe Equipment
When the operation is taking place in potentially explosive environments, such as those containing gas, vapour or dust, use only intrinsically safe radios that have been certified for use in hazardous environments. Ensure that the equipment is rated for use in the same type of atmosphere that is anticipated to exist in the confined space before commencing work.
Set a Timed Check-in Schedule
Agree a check-in time before the entry starts (typically every 5 minutes or 10 minutes). If a check-in is not heard then the surface attendant must start the emergency procedure for the confined space rescue instead of waiting to see if contact is re-established.
Agree Rope Signal Codes
Audio fails in confined spaces due to noise, distance or even the failure of the communication equipment itself. By setting up a simple signal using a rope (e.g. 1 pull for ‘I’m OK’, 2 pulls for ‘pull me out’) you can ensure that you have a method of communication that will work every time. This needs to be practised before entering the space.
Brief Everyone Before Entry
As confined space rescue forms part of the legal requirements of the Confined Spaces Regulations 1997, confined space rescue guidance and confined space rescue procedures should be practised with all team members before entry to a confined space.
A useful reference for Confined Space Rescue is https://www.agofirerescue.com/confined-space-rescue/.
Record all communication whilst the operation is in progress and refer to it afterwards for reference.
