Chapter 7A - Machinery Vessels of Less than 500GT
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Statutory Documents - MCA Publications - Yacht Code - January 2019 Edition - Part A - Large Yacht Code (up to 12 passengers) - Chapter 7A - Machinery Vessels of Less than 500GT

Chapter 7A - Machinery Vessels of Less than 500GT

Objective: This Chapter outlines the minimum requirements for machinery, which shall be in accordance with the requirements of a Recognised Organisation and shall cover the minimum aspects defined below, even if the machinery is not considered the primary means of propulsion. Existing Vessels which are not already Classed shall be taken into Class, however alternative arrangements for Short Range operation may be agreed by the Administration.

7A.1 General Requirements

(1) The machinery and its installation shall meet with the requirements of a Recognised Organisation. The Class Survey or Notation shall include, as a minimum, propulsion and electrical generation machinery and shafting. For existing and new vessels which operate with periodically unattended machinery spaces, the machinery and its installation shall meet the standards of SOLAS II-1/Part E - “Additional requirements for periodically unattended machinery spaces, so far as is reasonable and practicable to do so”.

(2) Plastic piping may be accepted where the piping and the arrangements for its use meet the requirements of the Fire Test Procedures Code.

(3) 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 shall be specially considered. Where gas turbines are fitted, attention shall be paid to the guidance contained within the IMO High Speed Craft Code, and installation shall be to the satisfaction of the Administration.

(4) Notwithstanding the requirements of Section 7A.1(1), in a fuel supply system to an engine unit, where a flexible section of piping is provided, connections shall be of a screw type or equivalent approved type. Flexible pipes shall be fire resistant/metal reinforced. Materials and fittings shall be of a suitable recognised national or international standard.

7A.2 Installation

(1) Notwithstanding the requirements referred to in 7A.1, the machinery, fuel tanks and associated piping systems and fittings shall be of a design and construction adequate for the service for which they are intended, and shall be so installed and protected as to reduce to a minimum any danger to persons during normal movement about the vessel, with due regard being made to moving parts, hot surfaces, and other hazards.

(2) Means shall be provided to isolate any source of fuel which may feed a fire in an engine space. A fuel shut-off valve(s) shall be provided which is capable of being closed from a position outside the engine space. The valve(s) shall be fitted as close as possible to the fuel tank(s).

(3) All external high-pressure fuel delivery lines between the high pressure fuel pumps and fuel nozzles shall be protected with a jacketed tubing system capable of containing fuel resulting from a high-pressure line failure. The jacketed tubing system shall include means for collection of leakage and arrangements shall be provided for an alarm to be given in the event of a fuel line failure.

(4) When a glass fuel level gauge is fitted it shall be of the "flat glass" type with self closing valves between the gauge and the tank.

7A.3 Additional Equivalence Considerations

(1) None

7A.4 Alternative Design and Arrangements

(1) Vessels may follow Section 1.9 on Alternative Design and Arrangements for this chapter as allowed by SOLAS II-1/55.

(2) The engineering analysis required by 1.9(3) shall be prepared and submitted to the Administration, based on the guidelinesfootnote and shall include, as a minimum, the following engineering analysis elements:

  • (a) determination of the ship type, machinery, electrical installations and space(s) concerned;

  • (b) identification of the prescriptive requirement(s) with which the machinery and electrical installations will not comply;

  • (c) identification of the reason the proposed design will not meet the prescriptive requirements supported by compliance with other recognized engineering or industry standards;

  • (d) determination of the performance criteria for the ship, machinery, electrical installation or the space(s) concerned addressed by the relevant prescriptive requirement(s):

    • (i) performance criteria shall provide a level of safety not inferior to the relevant prescriptive requirements contained in SOLAS II-1 parts C, D and E; and

    • (ii) performance criteria shall be quantifiable and measurable;

  • (e) detailed description of the alternative design and arrangements, including a list of the assumptions used in the design and any proposed operational restrictions or conditions;

  • (f) technical justification demonstrating that the alternative design and arrangements meet the safety performance criteria; and

  • (g) risk assessment based on identification of the potential faults and hazards associated with the proposal.

Parent topic: Part A - Large Yacht Code (up to 12 passengers)
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