E. Totally enclosed lifeboats

 

i. Totally enclosed lifeboats shall comply with the requirements of section 4.4 and in addition shall comply with the requirements of this section.

 

ii. Enclosure

Every totally enclosed lifeboat shall be provided with a rigid watertight enclosure which completely encloses the lifeboat. The enclosure shall be so arranged that:

it provides shelter for the occupants;

access to the lifeboat is provided by hatches which can be closed to make the lifeboat watertight;

except for free-fall lifeboats, hatches are positioned so as to allow launching and recovery operations to be performed without any occupant having to leave the enclosure;

access hatches are capable of being opened and closed from both inside and outside and are equipped with means to hold them securely in open positions;

except for a free-fall lifeboat, it is possible to row the lifeboat;

it is capable, when the lifeboat is in (be capsized position with the hatches closed and without significant leakage, of supporting the entire mass of the lifeboat, including all equipment, machinery and its full complement of persons;

it includes windows or translucent panels which admit sufficient daylight to the inside of the lifeboat with the hatches closed to make artificial light unnecessary;

its exterior is of a highly visible colour and its interior of a colour which does not cause discomfort to the occupants;

handrails provide a secure handhold for persons moving about the exterior of the lifeboat, and aid embarkation and disembarkation;

persons have access to their seats from an entrance without having to climb over thwarts or other obstructions; and

during operation of the engine with the enclosure closed, the atmospheric pressure inside the lifeboat shall never be above or below the outside atmospheric pressure by more than 20 hPa.

 

iii. Capsizing and re-righting

 

1. Except in free-fall lifeboats, a safety belt shall be fitted at each indicated seating position. The safety belt shall be designed to hold a person with a mass of 100 kg securely in place when the lifeboat is in a capsized position. Each set of safety belts for a seat shall be of a colour which contrasts with the belts for seats immediately adjacent. Free-fall lifeboats shall be fitted with a safety harness at each seat in contrasting colour designed to hold a person with a mass of 100 kg securely in place during a free-fall launch as well as with the lifeboat in capsized position.

2. The stability of the lifeboat shall be such that it is inherently or automatically self-righting when loaded with its full or a partial complement of persons and equipment and all entrances and openings are closed watertight and the persons are secured with safety belts.

3. The lifeboat shall be capable of supporting its full complement of persons and equipment when the lifeboat is in the damaged condition prescribed in paragraph 4.4.1.1 and its stability shall be such that, in the event of capsizing, it will automatically attain a position that will provide an above-water escape for its occupants. When the lifeboat is in the stable flooded condition, the water level inside the lifeboat, measured along the seat hack, shall not be more than 500 mm above the seat pan at any occupant seating position.

4. The design of all engine exhaust pipes, air ducts and other openings shall be such that water is excluded from the engine when the lifeboat capsizes and re-rights.

 

iv. Propulsion

 

1. The engine and transmission shall be controlled from the helmsman's position.

2. The engine and engine installation shall be capable of running in any position during capsize and continue to run after the lifeboat returns to the upright or shall automatically stop on capsizing and be easily restarted after the lifeboat returns to the upright. The design of the fuel and lubricating systems shall prevent the loss of fuel and the loss of more than 2500 ml of lubricating oil from the engine during capsize.

3. Air-cooled engines shall have a duct system to take in cooling air from, and exhaust it to, the outside of the lifeboat. Manually operated dampers shall be provided to enable cooling air to be taken in from, and exhausted to, the interior of the lifeboat.

 

v. Protection against acceleration

 

Notwithstanding paragraph 4.4.1.7, a totally enclosed lifeboat, except a free-tall lifeboat, shall be so constructed and tendered that the lifeboat renders protection against harmful accelerations resulting from an impact of the lifeboat, when loaded with its full complement of persons and equipment, against the ship's side at an impact velocity of not less than 3.5 m/s.