Ventilation Arrangement for Hazardous Spaces in Engine Room
The following engine room spaces are very hazardous on-board the ship and therefore, a special ventilation arrangement should be provided for safe entry:
(a) CO2 storage compartment
(b) Battery room
(c) Purifier flat
(d) Refrigerating machinery space
(e) Shaft tunnel
Ventilation Arrangement for Confined Spaces of Ships:
(a) CO2 storage compartment
–CO 2 compartment is situated on open deck , well ventilated and easily accessible .
– Its compartment door is opened outward.
– Boundaries between CO2 compartment should be watertight.
– Ventilation louver is fitted at the bottom near the floor , for the leaky CO2 to release to atmosphere because CO2 is more heavier than normal air.
– In some ships , exhaust fan is provided . Its suction is taken from bottom of the compartment and lead to open air deck . Exhaust system is separately provided from others.
– In some modern built ships , CO2 leakage warning alarm is provided
(b) Battery room
– Battery room is provided good ventilation, to prevent accumulation of Hydrogen gas and risk of battery explosion
– In the room , batteries should not be placed on the floor . It must be put on the level racks.
– Ventilation inlets are arranged below the battery level.
– Ventilation outlets are arranged at the top of a battery compartment.
– If the vent is other than direct to the outside , an exhaust fan is required. The fan is in the air stream from the compartment.
– The exhaust fan must be independent from other ventilation systems.
– All ventilation ducts should be made with corrosion resistant material.
(c) Purifier Flat
– Purifier flat is usually located at the E/R bottom floor. In some ships , purifiers are provided with separate compartment.
– Normally purifiers are operating with heaters to obtain efficient purification. Therefore , inflammable gases and some leakage of heated oil are usually accumulated in the Purifier flat . By this reason purifier space or room is provided with an exhaust blower to achieve better ventilation. , in addition to the fresh air supplied by E/R ventilation
– Out let form the purifier room blower lead to the open deck . Its louver is fitted with cover , normally open , but to close in case of fire in engine room , for CO2 release .
– The exhaust blower can be stopped from emergency remote station outside engine room .
(d) Refrigerating machinery space
– Ventilation system for Refrigerating plant is depend upon the type of refrigerant used.
– In Freon Gas refrigeration system, normal E/R ventilation is sufficient for the refrigerating plant space. If the plant is provided with separate compartment normal ventilated louver is provided.
– But for Ammonia and CO2 refrigeration system ,being they are harmful to human life , positive ventilation system i.e , exhaust fan must be used to repel any leakage of CO2 and NH3 gas to outside atmosphere. This reduce the risk of danger for explosion or suffocation.
(e) Shaft Tunnel – In shaft tunnel , natural draught fan is used. The force ventilation , supplied air for Engine Room is passing through shaft tunnel via opened water tight door. The hot & foul air from shaft tunnel may escape through emergency exit from shaft tunnel to open deck.
– In some ships , shaft tunnel ventilation is provided.
