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Working and Entry into an Enclosed Space

When working onboard a yacht there will be times where you will be required to enter into an enclosed space to access or maintain equipment or to complete some maintenance work. These spaces can be dangerous and without the correct procedures, injury and or death is likely.

So what is an enclosed space?

Enclosed spaces are defined by IMO Resolution A.1050 (27) and mean a space that has any of the following characteristics:

This includes but is not limited to: cargo spaces, fuel tanks, ballast tanks, pump-rooms, compressor rooms, cofferdams, chain lockers, void spaces, sewage tanks.

A person can survive 3 weeks without food, 3 days without water and 10-45 minutes in ice-cold water. But a person can only survive for 3 minutes without oxygen. Yes, it is that serious.

What procedures do I need to follow?

Risk Assess – Is this an enclosed space? Is it hazardous? What are the dangers involved? What do I need before entry into this space? What work is to be completed?

Authorisation of entry – Permits to work should be completed by a senior officer/Master and read through together. You need to read and understand the job you are undertaking along with the necessary equipment/PPE and procedures to be followed. You must both sign the permit to work.

Secure the space – Ensure the entrance to an enclosed space is secured against accidental entry. This is important if the door or access is left open to provide ventilation. Use warning signs displayed at every entrance. Ideally you should have someone stationed at the entrance. When preparing for entry the space needs to be isolated by means of tag out. This could also mean isolating electrical or hydraulic systems and placing signs at locations where controls are.

Ventilation – Before entering any enclosed space it needs to be sufficiently ventilated. This can be done by forced ventilation or natural ventilation. Natural ventilation is usually carried out by opening doors/hatches at each end of the relevant space. Forced ventilation can be done by using fans/blowers with a feed of air that contains sufficient oxygen levels. Ventilation should be carried out 24 hours prior to entry or until oxygen levels are safe to work in after testing. Sufficient lighting in the enclosed space should also be present. The oxygen levels should read 20% by volume before entering. Remember to check levels on entry into the space and re-check after any breaks.

Equipment – You need to have the correct rescue and resuscitation equipment present outside the enclosed space. Rescue equipment can include breathing apparatus, spare BA bottles, hoists, slings, tripod, radio and medical equipment. The person entering the enclosed space should also carry an oxygen analyzer with him inside the enclosed space and it should be on all the time to monitor the oxygen content.  As soon as level drops, the analyzer should sound an alarm and the space should be evacuated quickly without any delay.

Safe Practices – It is essential that someone is positioned outside the enclosed space and in regular contact with the crew working inside. You should have radios to contact them and you may also have sound signals in place if there is an emergency and people need to exit quickly.

Don’t make emotional decisions – If the worse were to happen it could be that you find your best friend or work colleague is found unresponsive in an enclosed space. STOP and think about what you are doing before entering. The chances are this could be due to lack of oxygen. Entering without the correct equipment could mean you end up in the same situation. EEDB’s should not be used to make a rescue. Make sure you raise the alarm and do not enter until you are wearing the correct breathing apparatus to rescue the injured crew member.

Closing the permit to work – Once the work has been completed the enclosed space should be secured and senior officers are made aware that there is no crew working in the space. The permit to work then needs to be closed.


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Working and Entry into an Enclosed Space

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Tim Clarke

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