Merchant Shipping Act, 1951 (Act No. 57 of 1951)SchedulesSecond ScheduleProtocol of 1978 Relating to the International Convention for the Safety of Life at Sea, 1974AnnexChapter II-2 : Construction—Fire Protection, Fire Detection and Fire ExtinctionPart B — Fire Safety Measures for Passenger Ships Carrying More than 36 PassengersRegulation 25 : Ventilation systems |
| (a) | In general, the ventilation fans shall be so disposed that the ducts reaching the various spaces remain within the main vertical zone. |
| (b) | Where ventilation systems penetrate decks, precautions shall be taken, in addition to those relating to the fire integrity of the deck required by Regulation 23 of this Chapter, 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, if necessary, be insulated as required by the appropriate tables in Regulation 20 of this Chapter. |
| (c) | The main inlets and outlets of all ventilation systems shall be capable of being closed from outside the space being ventilated. |
| (d) | Except in cargo spaces, ventilation ducts shall be constructed of the following materials: |
| (i) | Ducts not less than 0,075 square metres (116 square inches) in sectional area and all vertical ducts serving more than a single between deck space shall be constructed of steel or other equivalent material. |
| (ii) | Ducts less than 0,075 square metres (116 square inches) in sectional area shall be constructed of noncombustible materials. Where such ducts penetrate “A” or “B” Class divisions due regard shall be given to ensuring the fire integrity of the division. |
| (iii) | Short lengths of duct, not in general exceeding 0,02 square metres (31 square inches) in sectional area nor 2 metres (79 inches) in length, need not be incombustible provided that all of the following conditions are met: |
| (1) | The duct is constructed of a material of restricted fire risk to the satisfaction of the Administration; |
| (2) | the duct is used only at the terminal end of the ventilation system; and |
| (3) | the duct is not located closer than 0,6 metres (24 inches) measured along its length to a penetration of an “A” or “B” Class division, including continuous “B” Class ceilings. |
| (e) | Where a stairway enclosure is ventilated, the duct or ducts (if any) shall be taken from the fan room independently of other ducts in the ventilation system and shall not serve any other space. |
| (f) | All power ventilation, except machinery and cargo space ventilation and any alternative system which may be required under paragraph (h) of this Regulation, shall be fitted with controls so grouped that all fans may be stopped from either of two separate positions which shall be situated as far apart as practicable. Controls provided for the power ventilation serving machinery spaces shall also be grouped so as to be operable from two positions, one of which shall be outside such spaces. Fans serving power ventilation systems to cargo spaces shall be capable of being stopped from a safe position outside such spaces. |
| (g) | Where they pass through accommodation spaces or spaces containing combustible materials, the exhaust ducts from galley ranges shall be constructed of “A” Class divisions. Each exhaust duct shall be fitted with— |
| (i) | a grease trap readily removable for cleaning; |
| (ii) | a fire damper located in the lower end of the duct; |
| (iii) | arrangements, operable from within the galley, for shutting off the exhaust fan; and(iv) fixed means for extinguishing a fire within the duct. |
| (h) | Such measures as are practicable shall be taken in respect of control stations outside machinery spaces in order to ensure that ventilation, visibility and freedom from smoke are maintained, so that in the event of fire the machinery and equipment contained therein may be supervised and continue to function effectively. Alternative and separate means of air supply shall be provided; air inlets of the two sources of supply shall be so disposed that the risk of both inlets drawing in smoke simultaneously is minimized. At the discretion of the Administration, such requirements need not apply to control stations situated on, and opening on to, an open deck, or where local closing arrangements would be equally effective. |
| (i) | Ducts provided for ventilation of machinery spaces of Category A shall not in general pass through accommodation, service spaces or control stations, except that the Administration may permit relaxation from this requirement, provided that— |
| (i) | the ducts are constructed of steel, and are insulated to “A60” standard; or |
| (ii) | the ducts are constructed of steel and are fitted with an automatic fire damper close to the boundary penetrated and are insulated to “A60” standard from the machinery space to a point at least 5 metres (16 feet) beyond the fire damper. |
| (j) | Ducts provided for ventilation of accommodation, service spaces, or control stations shall not in general pass through machinery spaces of Category A, except that the Administration may permit relaxation from this requirement provided that the ducts are constructed of steel and automatic fire dampers are fitted close to the boundaries penetrated. |