7A MACHINERY - VESSELS OF LESS THAN 500 GT
Objective:- This section outlines the minimum requirements for Machinery Classification, which are to be in accordance with the requirements of one of the Classification Societies defined in the National Annex and should cover the minimum aspects defined below, even if the machinery is considered not the primary means of propulsion. Existing Vessels which are not already Classed should be taken into Class, however alternative arrangements for Short Range operation may be agreed by the Administration.
7A.1 General Requirements
7A.1.1 The machinery and its installation should, in general, meet with the requirements of one of the Classification Societies named in the National Annex. For existing and new vessels which operate with periodically unattended machinery spaces, the machinery and its installation should meet the standards of SOLAS regulations II-1/Part E - Additional requirements for periodically unattended machinery spaces, so far as is reasonable and practicable to do so.
Plastic piping may be accepted where the piping and the arrangements for its use meet the requirements of the IMO Fire Test Procedures Code.
7A.1.2 The requirements for main propulsion are based upon the installation of diesel powered units. When other types of main propulsion are proposed, the arrangements and installation should be specially considered. Where gas turbines are to be fitted, attention should be paid to the guidance contained within the IMO High-speed Craft Code, and installation is to be to the satisfaction of the Administration.
7A.1.3 Notwithstanding the requirements of paragraph 7A.1.1, in a fuel supply system to an engine unit, where a flexible section of piping is provided , connections should be of a screw type or equivalent approved type. Flexible pipes should be fire resistant/metal reinforced. Materials and fittings should be of a suitable recognised national or international standard.
7A.2 Installation
7A.2.1 Notwithstanding the requirements referred to in 7A.1, the machinery, fuel tanks and associated piping systems and fittings should be of a design and construction adequate for the service for which they are intended, and should be so installed and protected as to reduce to a minimum any danger to persons during normal movement about the vessel, due regard being made to moving parts, hot surfaces, and other hazards.
7A.2.2 Means should be provided to isolate any source of fuel which may feed a fire in an engine space fire situation. A fuel shut-off valve(s) should be provided which is capable of being closed from a position outside the engine space. The valve(s) should be fitted as close as possible to the fuel tank(s).
7A.2.3 All external high pressure fuel delivery lines between the high pressure fuel pumps and fuel nozzles should be protected with a jacketed tubing system capable of containing fuel resulting from a high-pressure line failure. The jacketed tubing system should include means for collection of leakage and arrangements should be provided for an alarm to be given in the event of a fuel line failure.
7A.2.4 When a glass fuel level gauge is fitted it should be of the "flat glass" type with self closing valves between the gauge and the tank.