3 Supply air requirements
Clasification Society 2024 - Version 9.40
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 1 - Design Guidelines and Operational Recommendations for Ventilation Systems in Ro-Ro Cargo Spaces - Appendix 1 - Ventilation of ro-ro cargo spaces - Requirements and basic calculations - 3 Supply air requirements

3 Supply air requirements

 The ventilation plant should be dimensioned to meet the following requirements.

  • (a) A minimum number of air changes according to SOLAS reg II-2/37, 38, 53; and

  • (b) The supply air requirements stipulated in the tables below.

Supply air requirements based on short-term exposure levels
Type of vehicle Operating cycle Supply air required per vehicle
Cars on ferries and ro-ro ships Normal operating cycle, starting from cold engine 7 - 8 m3/s
  Idling, starting from cold engine 5 - 6 m3/s
Long-distance lorries on ferries and ro-ro ships Normal operating cycle, starting from cold engine 6 - 7 m3/s
  Charging of compressed air systems for brakes, starting from cold engine (engine being idled at high speed) 7 - 8 m3/s
Supply air requirements based on long-term exposure levels
Type of vehicle Operating cycle Supply air required per vehicle
Cars on ferries and ro-ro ships Normal operating cycle, starting from cold engine 10 - 12 m3/s
  Idling, starting from cold engine 7 - 9 m3/s
Long-distance lorries on ferries and ro-ro ships Normal operating cycle, starting from cold engine 16 - 18 m3/s
  Charging of compressed air systems for brakes, starting from cold engine (engine being idled at high speed) 17 - 19 m3/s
Large loader trucks used for ro-ro ships Normal operating cycle, warm engines 22 - 24 m3/s
Small diesel trucks on ro-ro ships Normal operating cycle, warm engine 3 - 4 m3/s
Cars on car carriers Normal operating cycle, starting from cold engine 8 - 9 m3/s
  Normal operating cycle, warm engine 6 - 7 m3/s
  Normal operating cycle, idling, starting from cold engine 4 - 5 m3/s
Parent topic: Appendix 1 - Ventilation of ro-ro cargo spaces - Requirements and basic calculations
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