Section 7 Fire Protection and Fire Extinguishing Systems

701. General

Fire protection and fire extinguishing systems are to be in accordance with the requirements in Ch 3, Sec 6.

702. Structural Fire Protection

1. Fire Integrity of Exterior Bulkheads

For superstructures and deck houses enclosing accommodation and machinery spaces, the exterior bulkheads facing the cargo area and side bulkheads within a distance of 3 m from the end bulk- head facing the cargo area are to be of steel construction and insulated, up to the underside of the deck of the navigation bridge, to “A-60” standard as defined in Chapter II-2/Regulation 3 of the International Convention for the Safety of Life at Sea (SOLAS) 1974, as amended with the ex- ception of the following:

(1) Insulation to “A-0” standard is acceptable provided the bulkheads are protected by a fixed wa- ter-spray system with a minimum water capacity of 10 liters/minute/m2.

(2) Insulation to “A-0” standard is acceptable without a water-spray system provided the bulkheads are at least one deck above the cargo area and are at least 10 meters measured horizontally away from a vertical plane of the recovered oil tanks and sources of oil or vapor release (such

as tank vents, valves, flanges, and fittings).

Access doors and closing appliances for openings are to meet the same requirements as the bulkhead.

2. Openings in Exterior Bulkheads

Accesses and ventilation openings for spaces containing essential equipment are to be available for use at all times. However, accesses and openings not needed during oil recovery operations may be provided the arrangements comply with the following:

(1) Access doors, air inlets and openings to accommodation spaces, service spaces, control stations

and machinery vided they are

spaces may face the cargo area and/or be located within the above limits pro- located at least one deck above the cargo area and are at least 3 meters meas-

56 Guidance for Offshore Support Vessels 2015

ured horizontally away from a vertical plane of the recovered oil tanks and sources of oil or vapor release.

(2) Access doors are self-closing gas-tight, secured (i.e., kept closed), and fitted with signs indicat-

ing that the doors are to remain closed during oil recovery operations. In addition, the doors are to have a fire rating equivalent to the boundary in which they are installed.

(3) All access and means of escape otherwise required by the Guidance are met without the use of

the secured access doors.

(4) Portlights and windows fitted in locations other than the navigation bridge may face the cargo area and/or be located within the limits provided they are of the fixed (non-opening) type. They are to be fitted with deadlights constructed of steel or other equivalent material, which must be secured during oil recovery operations.

(5) Bolted plates for the removal of machinery may face the cargo area and/or be fitted within the

limits.

703. Spill Coaming

Oil handling areas and equipment on deck are to be provided with a coaming around all pumps, transfer flanges and other connections where leakage may be expected. Each coaming is to be ad- equately sized to contain deck spills and prevent recovered oil from entering accommodation, ma- chinery, control and service spaces or passing overboard. The coaming is to have a height of at least 150 mm.

Where drains are provided for the coaming, closing devices for these drains are to be permanently attached.

Spill coamings may be of the removable type.

704.

1.

2.

Ventilation systems installed in hazardous areas

Recovered oil pump rooms and enclosed spaces in which oil recovering apparatus is located are to be provided with an exhaust-type mechanical ventilation system with an air change rate not less than 20 times per hour. Inlets of the ventilation system are to be located as high as practicable in non- hazardous areas. However, the ventilation system for small recovered oil pump rooms which contain no source of ignition may be dispensed with the requirements in this paragraph, subject to the approval of the Society.

Driving motors for fans of the ventilation systems for hazardous areas are to be installed outside ventilation ducts. Fans and casings are to be designed so as not to emit sparks due to contact of moving parts or formation of static electricity.

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