3.11 Measurements in machinery spaces
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Statutory Documents - IMO Publications and Documents - Resolutions - Maritime Safety Committee - Resolution MSC.337(91) – Adoption of the Code on Noise Levels on Board Ships – (Adopted on 30 November 2012)The Annex below is consolidated into Resolution MSC.337(91) - Annex – Code on Noise Levels on Board Ships - Chapter 3 – Measurement - 3.11 Measurements in machinery spaces

3.11 Measurements in machinery spaces

  3.11.1 Measurements shall be taken at the principal working and control stations of the seafarers in the machinery spaces and in the adjacent control rooms, if any, special attention being paid to telephone locations and to positions where voice communication and audible signals are important.

  3.11.2 Measurements should not normally be taken closer than 1 m from operating machinery, or from decks, bulkheads or other large surfaces, or from air inlets. Where this is not possible, measurement shall be taken at a position midway between the machinery and adjacent reflecting surface.

  3.11.3 Measurements from machinery which constitutes a sound source should be taken at 1 m from the machinery. Measurement should be made at a height of between 1.2 m to 1.6 m above the deck, platform or walkway as follows:

  • .1 at a distance of 1 m from, and at intervals not greater than 3 m around, all sources such as:

    • - main turbines or engines at each level

    • - main gearing

    • - turbo-blowers

    • - purifiers

    • - electrical alternators and generators

    • - boiler firing platform

    • - forced and/or induced draught fans

    • - compressors

    • - cargo pumps (including their driving motors or turbines)

    • In order to avoid an unnecessarily large and impractical number of measurements and recordings in the case of large engines and of machinery spaces where the measured sound pressure level in dB(A) at the intervals above does not vary significantly, it will not be necessary to record each position. Full measurement at representative positions and at the positions of maximum sound pressure level shall, however, be made and recorded, subject to at least four measurements being recorded at each level;

  • .2 at local control stations, e.g. the main manoeuvring or emergency manoeuvring stand on the main engine and the machinery control rooms;

  • .3 at all other locations not specified in .1 and .2 which would normally be visited during routine inspection, adjustment and maintenance;

  • .4 at points on all normally used access routes, unless covered by positions already specified above, at intervals not greater than 10 m; and

  • .5 in rooms within the machinery space, e.g. workshops. In order to restrict the number of measurements and recordings, the number of recordings can be reduced as in .1, subject to a total of at least four measurements (including those specified in this paragraph) being recorded at each machinery space level up to upper deck.

Parent topic: Chapter 3 – Measurement
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