In our Know Your Ship blog with Sentini Marine, we cover a range of topics about keeping yourself and others safe onboard. Topics range from fire fighting to dealing with medical emergencies. In this article, it’s all about immersion suits. 

Immersion suits are designed to keep you afloat and protect you from hypothermia if immersed in cold water after abandoning a vessel, especially in the open ocean. Hours spent in the water, even in warmer climates, can cause your body temperature to drop significantly and put you in danger of hypothermia.

Hypothermia happens when the body temperature falls below 35 degrees C. This effects the brain, heart and other internal organs. Full hypothermia happens after approximately 30 minutes, it will lead to a loss of consciousness and then death.

Immersion Suit Capabilities

Every vessel over 24 meters should have an immersion suit onboard for every crew member and passenger, they are designed so that they can be donned in under 2 minutes.

The impact protection is up to 4.5 meters, meaning you can jump into the water wearing it from that height without damaging or dislodging the suit. It will keep your body temperature from dropping more than 2 degrees over a six-hour period. 

How To Put It On

a) Lay the suit out on the deck and sit on it. Insert your legs into the suit using plastic bags for ease. Keep your boots and other clothing on for insulation and protection in the water.

b) Insert your non-dominant arm into the suit first (if you’re left handed insert right hand and right handed insert left hand).

c) Pull the hood over your head with your free hand.

d) Insert you dominant arm in last. Carefully zip up the suit and secure the flap over your face.

e) Ensure that all straps and hoses are securely fastened to prevent snagging or injury. Do not inflate the air bladder until you are in the water.

Things To Consider

  • Do you know what type of immersion suits are onboard your vessel, do they require a life jacket to be worn with them?
  • Do you know where your immersion suit is located onboard?
  • Are you practicing putting it on, can you do it in under 2 minutes?
  • Are you familiar with the location of the guest immersion suits?
  • Would you be able to help a child put their suit on whilst wearing yours?

Staying afloat and staying warm will be the only two things that matter if you find yourself in the open sea, ensure you know where the immersion suits are stored and how to get one on quickly. Familiarity with the vessel you work on and its life saving equipment is essential, don’t be passive about it. Your safety, and the safety of your crew mates, is your responsibility.

Sentini Marine supply bespoke Technical Operating Manuals and training to both the commercial shipping world and private yachts.

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