14A.4 Ventilation systems

  14A.4.1 Ventilation fans for machinery spaces and enclosed galleys are to be capable of being stopped, and main inlets and outlets of ventilation systems closed, from outside the spaces being served. This position should not be readily cut off in the event of a fire in the spaces served.

  14A.4.2 Ventilation ducts for Category 'A' machinery spaces, galleys, spaces containing vehicles or craft with fuel in their tanks, or lockers storing such fuels, are generally not to pass through accommodation spaces, service spaces or control stations. Where this is unavoidable, the trunking should be constructed of steel at least 3mm thick or equivalent to the satisfaction of the administration. The ducting within the accommodation should be fitted with:

• .1 fire insulation to A-30 (B-15 on Short Range Yachts) standard to a point at least 5 metres from the machinery space or galley; and

• .2 automatic fire dampers located in the deck or bulkhead within the accommodation where the trunking passes from the machinery space or galley into the accommodation. These automatic fire dampers are also to be manually closable from outside the galley or machinery space.

• .3 fixed means for extinguishing a fire within the galley exhaust duct.

  14A.4.3 Ventilation ducts for accommodation spaces, service spaces or control stations are not to pass through Category 'A' machinery spaces, galleys, spaces containing vehicles or craft with fuel in their tanks, or lockers storing such fuels, unless the ducts are constructed of steel and arranged to preserve the integrity of the division.

  14A.4.4 Store-rooms containing highly flammable products are to be provided with ventilation arrangements that are separate from other ventilation systems. Ventilation is to be arranged to prevent the build up of flammable vapours at high and low levels. The inlets and outlets of ventilators are to be positioned so that they do not draw from or vent into an area which would cause undue hazard, and are to be fitted with spark arresters.

  14A.4.5 Ventilation systems serving Category 'A' machinery spaces are to be independent of systems serving other spaces.

  14A.4.6 All enclosed spaces containing free standing fuel tanks are to be ventilated independently of systems serving other spaces.

  14A.4.7 Ventilation is to be provided to prevent the accumulation of dangerous concentrations of flammable gas which may be emitted from batteries.

  14A.4.8 Ducts provided for tumble driers are to be fitted with suitably located cleaning and inspection openings.