Chapter 7 – Main Machinery

  7.1.1 The design, rating, installation, operation and maintainability of shipboard engineering systems should be suitable for navigation in polar ice-covered waters^footnote.

  7.1.2 In the event of damage, malfunction or failure of any machinery component, means should be provided to control and limit any resulting emission of pollutants to within the confines of the ship’s hull.

  7.1.3 Special attention should be drawn to the fact that harsh weather conditions often occur in polar waters and that the propulsion effect plays a significant role in relation to the steering ability.

  7.1.4 The layout and construction of machinery essential for the safe operation of the ship should be such that repairs which can be affected using the resources on board may be completed safely and effectively. Ventilation systems should provide sufficient air at an appropriate temperature for the operation of machinery.

  7.1.5 For Polar Class ships which may be laid up in polar waters, materials for all systems with the potential of polluting should be suitable for preventing pollution at the lowest ambient temperatures to which they may be subjected and should be suitable to avoid pollution and ensure safe operation on re-activation of the systems.

  7.2.1 The main propulsion machinery should be designed so that the effects of loads with the potential to damage the system are limited to those components which can be readily repaired, replaced or reset. The reliability and availability of the equipment and systems should be considered.

  7.2.2 Main propulsion machinery and all auxiliary machinery essential to the propulsion system, should be:

• .1 designed for loads and vibrations resulting from propeller/hull/rudder-ice interactions;

• .2 located to provide protection from freezing spray, ice and snow; and

• .3 designed to operate when the ship is inclined at any combined angle of heel or trim that may be expected during operations in ice.

  7.2.3 Stern tube bearings, seals and main propulsion components located outside the hull should not leak pollutants. Non-toxic biodegradable lubricants are not considered to be pollutants.

  7.2.4 The installed propulsive power should be sufficient to ensure that the ship can navigate safely and with effective icebreaking capability, as appropriate, without risk of structural damage or pollution under the design ice, weather and anticipated operational conditions.

  7.2.5 Piping and intake systems associated with the main propulsion plant and auxiliary machinery essential to the propulsion system should be designed so as not to be affected by the impact of the polar environment.