Section 4 Machinery room arrangements

4.1.1 Accessibility, for attendance and maintenance purposes, is to be provided for machinery plants.

4.2.1 Bedplates, thrust seatings and other fastenings are to be of robust construction, and the machinery is to be securely fixed to the ship’s structure to the satisfaction of the Surveyor.

4.2.2 Where the machinery is installed on resilient mountings, linear vibration (steady state and transient) is not to exceed the limiting values agreed with the manufacturer of the machinery or those of the resilient mountings. Misalignment arising from such vibration is not to impose excessive loading on machinery components within the system.

4.2.3 The Shipbuilder is to ensure that the vibration levels of flexible pipe connections, shaft couplings and mounts remain within the limits specified by the component manufacturer for the start-stop operation and the natural frequencies of the system. Due account is to be taken of any creep that may be inherent in the mount.

4.2.4 Anti-collision chocks are to be fitted together with positive means to ensure that manufacturers' limits are not exceeded. Suitable means are to be provided to accommodate the propeller thrust.

4.3.1 All spaces, including engine and cargo pump spaces, where flammable or toxic gases or vapours may accumulate, are to be provided with adequate ventilation under all conditions.

4.3.2 Machinery spaces with a total installed power rating exceeding 375 kW or containing oil fired equipment shall be adequately ventilated so as to ensure that when machinery or boilers therein are operating at full power in all weather conditions, a sufficient supply of air is maintained to the spaces for the safety and comfort of personnel and the operation of the machinery. Any other machinery space shall be adequately ventilated, as appropriate for the purpose of that machinery space.

4.3.3 The ventilation of a closed engine room on board of tankers is to be arranged such that with an ambient temperature of 20°C the average temperature of the engine room will not exceed 40°C.

4.3.4 The supply of air for the main propulsion engine(s) may not been taken from spaces protected by a fixed fireextinguishing installation. This requirement is not applicable if two independent gastight separated machinery rooms are available or if next to the machinery room a steerable bow thruster installation is available in a separate engine room capable of propelling the ship in case of a main machinery room fire. Plans of the independent steerable bow thrust installation are to be submitted for consideration in such cases, see Pt 5, Ch 17 Steerable Bow Thrusters.

4.4.1 All surfaces of machinery where the surface temperature may exceed 220°C and where impingement of flammable liquids may occur, are to be effectively shielded to prevent ignition. Where insulation covering these surfaces is oil-absorbing or may permit penetration of oil, the insulation is to be encased in steel or equivalent.

4.5.1 In machinery spaces two means of escape are generally to be provided, see Pt 3, Ch 6, 7.1 General.

4.6.1 At least one means of communication is to be provided between the wheelhouse and the engine control station.