The Merchant Shipping (Fire Protection: Large Ships) Regulations 1998

Ventilation systems

60.—(1) Wherever practicable the system of ducts leading from each ventilation fan shall be within one main vertical or horizontal zone.

(2) Where ventilation systems penetrate decks precautions shall be taken, in addition to those relating to the fire integrity of the decks required by regulation 58(1), to reduce the likelihood of smoke and hot gases passing from one between-deck space to another through the system. In addition to insulation requirements contained in this regulation, vertical ducts shall be insulated as required by the Tables in Schedules 1 and 2 in Merchant Shipping Notice MSN 1667 as appropriate.

(3) (a) Ducts serving a stairway enclosure shall be taken from the fan room independently of other ducts in the ventilation system and shall not serve any other space.

(b) In the case of a ship constructed on or after 1st October 1994, carrying more than 36 passengers stairway enclosures shall be ventilated and shall be served only by an independent fan and duct system which shall not serve any other spaces in the ventilation system.

(4) There shall be provided for every control station situation below deck, other than a control station situated in the machinery space, means to ensure ventilation, visibility and freedom from smoke within it so that, in the event of a fire in the ship, the equipment it contains may be operated effectively. Unless a control station is situated on, and has access to, an open deck or is provided with local closing arrangements equally effective to maintain ventilation, visibility and freedom from smoke in the event of a fire in the ship, there shall be provided at least two entirely separate means of supplying air to such control stations and the air inlets to these sources of supply shall be so situated that the risk of both drawing in smoke simultaneously is, as far as practicable, eliminated.

(5) Ventilation ducts except those in cargo spaces, shall be constructed in accordance with the specifications set out in Schedule 3 in Merchant Shipping Notice MSN 1667.