Accommodation ventilation arrangements
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.648 – Guidelines for the Operation, Inspection and Maintenance of Ship Sewage Systems – (Adopted on 6 June 1994) - Annex - Guidelines for the Operation, Inspection and Maintenance of Ship Sewage Systems - Accommodation ventilation arrangements

Accommodation ventilation arrangements

  12 Particular attention should be paid to the exhaust and supply systems in toilet and washing areas. Ventilation systems to all compartments of a ship should be designed, installed and balanced to ensure satisfactory distribution of air. They should be maintained in a clean and efficient condition to achieve the designed air changes throughout the service life of the vessel. In general, attention should be paid to the following:

  • .1 Examination of extraction grills, louvres, ducts, etc., in order to ensure that they are clear and free of accumulations of dirt, fluff, etc.

  • .2 Checking the adjustment of extraction louvres or cones to ensure an even extraction rate from all spaces. However, when satisfactorily adjusted, there should be no interference with these units as the adjustment of one unit can seriously affect the rate of extraction through other units. The design of these fittings should be such that they are not capable of manual adjustment without the use of special tools or equipment. Ensure that extraction units are never blocked off for any reason.

  • .3 Ensuring that air extraction from alleyways is operating efficiently and that essential air-gaps under cabin doors, etc., have not been blocked off.

  • .4 Ensuring that the forced ventilation of cabin spaces is operating efficiently.

  • .5 Inspecting the associated elements of ventilating systems, including:

    • .5.1 Fans: Checking the direction of rotation, condition of impellers, etc.

    • .5.2 Flaps and dampers: Ensuring that they have not become detached from the operating mechanisms and that they are actually open when indicating open.

    • .5.3 Goosenecks and vents: Ensuring that they are clear of any obstructions, that grilles or meshes are not painted over, etc.

    • .5.4 Piping or ducting: Ensuring that these are intact and free from leaks throughout their length, especially where they pass through accommodation areas.


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