(1) The arrangements for providing foam shall be capable of delivering foam to the entire cargo tanks deck area as well as into any cargo tank, the deck of which has been ruptured.
(2) The deck foam system shall be capable of simple and rapid operation. The main control station for the system shall be suitable located outside the cargo area adjacent to the accommodation paces and readily accessible and operable in the event of fire in the areas protected.
(3) The rate of supply of foam solution (that is, the mixture of foam concentrate and water before expansion) shall be not less than the following whichever is the greatest:
- 0.6 litre per minute per square metre of cargo tanks deck area, where cargo tanks deck area means the maximum breadth of the ship times the total longitudinal extent of the cargo tank spaces.
- 6 litre per minute per square metre of the horizontal sectional area of the single tank having the largest such area; or
- 6 litre per minute per square metre of the area protected by the largest monitor, such area being entirely forward of the monitor, but not less than 1, 250 litres per minute.
(4) Sufficient foam concentrate shall be supplied to ensure atleast 20 minutes of foam generation in ship fitted with an inert gas system complying with SOLAS to these Regulations or 30 minutes of foam generation in ships not fitted with an inert gas by system when using the solution rates stipulated in paragraphgraph (3) .
The foam expansion ratio (that is, the ratio of the volume of foam produced to the volume of the mixture of foam concentrate and water before expansion) shall not generally exceed 12 to 1.
(5) Foam from the fixed system shall be supplied by means of monitors and foam applicators. At least 50 per cent of the foam solution rate required in sub-paragraphs (a) and (b) of paragraph (3) shall be delivered from each monitor. On tankers of less than 4,000 tonnes deadweight, applicators may be substituted for an installation of monitors. In such a case the capacity of each applicator shall be at least 25 per cent of the foam solution rate required in sub-paragraphgraph (a) or (b) of paragraph (3).
(6) (a) The number and position of monitors shall be such as to comply with paragraphgraph (1). The capacity of any monitor shall be at least 3 litres per minute of foam solution per square metre or deck area protected by that monitor, such area being entirely forward of the monitor. such capacity shall be not less than 1,250 litres per minute.
(b) The distance from the monitor to the farthest extremely of the protected area forward of that monitor shall not be more than 75 per cent of the monitor throw in still air conditions.
(7) A monitor and hose connection for a foam applicator shall be situated both port and starboard at the front of the poop or accommodation spaces facing the cargo tanks deck. On tankers of a deadweight of less than 4,000 tonnes not fitted with monitors a hose connection for a foam applicator shall be situated both port and starboard at the front of the poop or accommodation spaces facing the cargo tanks deck.
(8) The capacity of any applicator shall be not less than 400 litres per minute and the applicator throw in still air conditions shall be not less than 15 metres. The number of foam applicators provided in accordance with the requirements of paragraphgraph (5) shall be not less than four. The number and disposition of foam main outlets shall be such that foam from at least two applicators can be directed on to any part of the cargo tank deck area.
(9) Valves shall be provided in the foam main, and in the fire main when this is an integral part of the deck foam system, immediately forward of any monitor position to isolate damaged sections of those mains.
(10) Operation of a deck foam system at its required output shall permit the simultaneous use of the minimum required number of jets of water at the required pressure from the fire main.