Appendix 1 - Example of general arrangement of ventilation systems in ro-ro cargo spaces
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.729 – Design Guidelines and Operational Recommendations for Ventilation Systems in Ro-Ro Cargo Spaces – (Adopted on 4 July 1996) - Part 2 - Operational Recommendations for Minimizing Air Pollution in Ro-Ro Cargo Spaces - Appendix 1 - Example of general arrangement of ventilation systems in ro-ro cargo spaces

Appendix 1 - Example of general arrangement of ventilation systems in ro-ro cargo spaces

 The general arrangement of the ventilation system is illustrated in the attached figure.

The lower deck (the tank-top) is served by eight fans: four supply air fans in the forward part of the deck, and four exhaust air fans aft. Each duct has two openings, one at about deck level and one at the deckhead. An auxiliary system of directing air jets is included for mixing the air. The supply air capacity is 84 m3/s, which should be fully adequate for the relevant cargo handling (3 or 4 trucks).

The part of the deck immediately aft of the lift can constitute a stagnant or screened area when the lift is descending, as there will then be an opening in the main deck.

Two supply air fans and two exhaust air fans provide the ventilation at sea, giving six air changes per hour when the cargo space is empty according to regulation II-2/53 of SOLAS 74, as amended.

The intermediate deck (the main deck) is served by eight supply air fans at the forward end. Each duct has two openings, one at deck level and one at the deckhead. The exhaust air is removed by natural ventilation through the ramp in the stern. An auxiliary system is included for mixing the air. The supply air capacity is 168 m3/s, which will normally be fully adequate during cargo handling (6 - 8 trucks). Two exhaust air fans, primarily intended for ventilation of the hold when the ship is under way, are located at the stern.

When the ship is under way, ventilation giving six air changes per hour when the ro-ro cargo space is empty is provided by two supply air fans and the two exhaust air fans in the stern.

Each of the deck garages (weather decks) is served by three supply air fans. Each duct has three openings with a facility for directing the air to the area in which cargo handling is in progress. The supply air capacity of 64 m3/s should be adequate to cope with the exhaust emissions from 6-8 cars or from 2 or 3 trucks handling the cargo. The exhaust air is discharged through an opening into the weather deck. The aft deck garage has exhaust air openings in the forward bulkhead for ventilation of the ro-ro cargo space when the ship is under way.

Ventilation at sea, giving six air changes per hour in an empty ro-ro cargo space, is provided by one supply air fan.

Figure 2 Example of Arrangement of Ventilation systems of Ro-Ro Cargo Spaces

Parent topic: Part 2 - Operational Recommendations for Minimizing Air Pollution in Ro-Ro Cargo Spaces
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