Requirements on Carrying Capacity of Lifeboats

• No Lifeboat shall be approved to accommodate more than 150 persons.

• The number of persons which a lifeboat to be launched by falls shall be permitted to accommodate shall be equal to the lesser of:

• The number of persons having an average mass of 75 kg (for a lifeboat intended for a passenger ship) or 82.5 kg (for a lifeboat intended for a cargo ship), all wearing lifejackets, that can be seated in a normal position without interfering with the means of propulsion or the operation of any of the lifeboat's equipment; or 
• The number of spaces that can be provided on the seating arrangements. The shapes may be overlapped, provided footrests are fitted and there is sufficient room for legs and the vertical separation between the upper and lower seat is not less than 350 mm. 

• Each seating position shall be clearly indicated in the lifeboat. 

Reference: 

1. IMO Publications & Documents - International codes - LSA Code - Chapter IV - Survival Craft 
2. IMO Publications & Documents - Resolutions - Maritime Safety Committee - Resolutions.MSC.48(66).