Skip to main content

SOLAS requirement for low and high expansion foam system

SOLAS requirement of Low Expansion foam firefighting system

  • Foam system should be approved by the administration
  • Foam monitors should have the capacity to discharge 3litres/m2/minute.
  • The system should contain five times the volume the of largest space
  • Expansion ratio should not exceed 1000:1
  • The main control station should be located away from the cargo area, adjacent to accommodation space.
  • The system shall be capable to discharge foam, in no more than 5 minutes, the quantity should be sufficient to form a foam blanket over the largest single area over which oil fuel is liable to spread.
  • The system shall be capable to supply foam not less than 20 minutes on tanker fitted with inert gas system and not less than 30 minutes on tankers not fitted with the inert gas system.
  • The rate of supply of foam shall not be less than the greatest of following
    1. 0.6 l/min per square meter of cargo tanks deck area, where cargo tanks deck area means the maximum breadth of the ship multiplied by the total longitudinal extent of the cargo tank spaces
    2. l/min per square meter of the horizontal sectional area of the single tank having the largest such area; or
    3.  3 l/min per square meter of the area protected by the largest monitor, such area being entirely forward of the monitor, but in no case should the output of any monitor be less than 1,250 l/min.
  • The capacity of an applicator shall not be less than 400l/minute and should capable of through foam not less than 15 meters in still air condition.

SOLAS regulation for High Expansion Foam

  • The system shall be approved by the administration.
  • The system shall be capable of manual activation and shall be designed to produce foam at the required rate within 1 minute of release. Automatic activation is not permitted unless appropriate interlocks are provided.
  • The system and control station shall be located away from protected space.
  • The quantity of foam concentration shall be sufficient to produce the foam volume equal to at least five times the volume of largest protected space(E/R), at the nominal expansion ratio, or enough for 30 minutes of full operation for the largest protected space, whichever is greater.
  • The system should be capable of rapid discharging foam @ at least 1 meter in depth per minute
  • The operating instruction for the system shall be displayed at main as well as local control stations.
  • If an IC engine is used as a prime mover for seawater pump for the system then the fuel tank of that engine shall contain sufficient fuel to run the pump on full load for at least 3 hours and reserves of fuel shall be available outside the machinery space of category A to enable to run the pump on full load for additional 15 hours.
  • The foam generators shall be located at the place where adequate fresh air supply can be arranged.
  • The arrangement shall be provided for the crew to safely check the quantity of foam concentration.
  • The arrangement of foam generators and piping of the foam system in the protected space shall not interfere with the access to the installed machinery for routine maintenance activities.
  • The system shall be supplied main as well as the emergency source of power.
  • The foam generator room shall be ventilated to protect against overpressure, and shall be heated to avoid the freezing


  1. In low expansion foam what is the largest space the the largest volume of that cargo hold


Post a Comment

If you have any doubts.Please let me know

Popular posts from this blog

Why is a man hole door elliptical in shape?

Any opening in a pressure vessel is kept to a minimum and for a man entry an elliptical hole  is lesser in size than the corresponding circular hole. More over it is prime concern to have a  smoothed generous radius at the corners to eliminate stress concentration. Hence other  geometrical shapes like rectangle and square are ruled out.  To compensate for the loss of material in the shell due to opening, a doubler ring has to be  provided around the opening. The thickness of the ring depends on the axis length along the  dirrection in which the stresses are maximum and the thickness of the shell. It is important to  align the minor axis along the length of the vessel, as the stress in this direction is  maximum. Longitudinal stress: Pd/2t where P= pressure inside the vessel, d= diameter of the arc, t=  thickness of the shell plating  Circumferential stress: Pd/4t  More over a considerable material and weight saving is achieved as minor is along the  direction of maximum stress.

Shell Expansion Plan

It is a two dimensional drawing of a three dimensional surface of the ship’s hull form. This plan is very useful for the following information:It is used for marking the location of a hull Damage on this plan by identifying the strake number , letter and frame number so that the exact location of the damage and also suggested repairs are marked in a localised copy. The shell expansion can be used for finding areas of painting surfaces such as topside, boot topping and bottom areas by applying Simpsons rules directly.  In the shell expansion the vertical scale used is different from the horizontal scale and a suitable adjustment has to be made when calculating areas. This becomes useful in solving disputes concerning areas of preparation and painting. It gives information on the thickness of the original strake which is indicated by the number in the circle shown in the strake.  The quality of steel used is also shown by letters A,B,D E and AH, BH,DH, EH.