What is true regarding the combined capacity rating of IG blowers in a vessel?

The combined capacity rating of Inert Gas (IG) blowers on a vessel is particularly important for ensuring that the system can adequately manage the inert gas for cargo tank pressurization and safety during loading and unloading operations. The correct choice indicates that the combined capacity must exceed the maximum discharge rate by 125%.

This requirement ensures that the system has sufficient capacity to maintain a positive pressure in the cargo tanks even under fluctuating operational conditions. It also provides a safety margin that accounts for potential inefficiencies or obstacles in the system. By exceeding the maximum discharge rate by this specified percentage, the vessel ensures reliable operation of the inert gas system, adequately preventing the formation of flammable atmospheres and aiding in the safe management of volatile cargoes.

Understanding this requirement is essential for the design and operation of tankers to comply with safety regulations and to promote safe operational practices.