Regulation 25 - Immersion suits
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Conventions - SFV - International Convention for the Safety of Fishing Vessels (The Torremolinos Convention)Regulations for the Construction and Equipment of Fishing Vessels - Chapter VII - Life-Saving Appliances and Arrangements - Part C - Life-Saving Appliances Requirements - Regulation 25 - Immersion suits

Regulation 25 - Immersion suits

  (1) General requirements for immersion suits

  • (a) The immersion suit shall be constructed with waterproof materials such that:

    • (i) it can be unpacked and donned without assistance within 2 min taking into account any associated clothing, and a lifejacket if the immersion suit is to be worn in conjunction with a lifejacket;

    • (ii) it will not sustain burning or continue melting after being totally enveloped in a fire for a period of 2 s;

    • (iii) it will cover the whole body with the exception of the face. Hands shall also be covered unless permanently attached gloves are provided;

    • (iv) it is provided with arrangements to minimize or reduce free air in the legs of the suit;

    • (v) following a jump from a height of not less than 4.5 m into the water there is no undue ingress of water into the suit.

  • (b) An immersion suit which also complies with the requirements of regulation 24 may be classified as a lifejacket.

  • (c) An immersion suit shall permit the person wearing it, and also wearing a lifejacket if the immersion suit is to be worn in conjunction with a lifejacket to:

    • (i) climb up and down a vertical ladder at least 5 m in length;

    • (ii) perform normal duties during abandonment;

    • (iii) jump from a height of not less than 4.5 m into the water without damaging or dislodging the immersion suit, or being injured;

    • (iv) swim a short distance through the water and board a survival craft.

  • (d) An immersion suit which has buoyancy and is designed to be worn without a lifejacket shall be fitted with a light complying with the requirements of regulation 24(3) and the whistle prescribed by regulation 24(1)(f).

  • (e) If the immersion suit is to be worn in conjunction with a lifejacket, the lifejacket shall be worn over the immersion suit. A person wearing such an immersion suit shall be able to don a lifejacket without assistance.

  (2) Thermal performance requirements for immersion suits

  • (a) An immersion suit made of material which has no inherent insulation shall be:

    • (i) marked with instructions that it must be worn in conjunction with warm clothing;

    • (ii) so constructed that, when worn in conjunction with warm clothing and with a lifejacket if the immersion suit is to be worn with a lifejacket, the immersion suit continues to provide sufficient thermal protection following one jump by the wearer into the water from a height of 4.5 m to ensure that when it is worn for a period of l h in calm circulating water at a temperature of 5°C the wearer's body core temperature does not fall more than 2°C.

  • (b) An immersion suit made of material with inherent insulation when worn either on its own or with a lifejacket, if the immersion suit is to be worn in conjunction with a lifejacket, shall provide the wearer with sufficient thermal insulation following one jump into the water from a height of 4.5 m to ensure that the wearer's body core temperature does not fall more than 2°C after a period of 6 h immersion in calm circulating water at a temperature of between 0°C and 2°C.

  • (c) The immersion suit shall permit the person wearing it with hands covered to pick up a pencil and write after being immersed in water at 5°C for a period of 1 h.

  (3) Buoyancy requirements

 A person in fresh water wearing either an immersion suit complying with the requirements of regulation 24 or an immersion suit with a lifejacket shall be able to turn from a face-down to a face-up position in not more than 5 s.


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