TM 55-1930-209-14&P-1 Table 7-2.  Major Components of Voids Ventilation System Component Quantity Function Location Mushroom 2 Exhaust air from voids 4 port On topdeck for fans exhaust and starboard 9 and 10 air roof outlets Ventilating fans 2 Exhaust air from voids 4 port In ROWPU space near aft (vertical) and starboard bulkhead Ventilating fans 2 Blow forced air into  voids In ROWPU space high on (horizontal) port and starboard bulkheads Round blower 2 Protect fan motors, provide In ROWPU space high on covers with fittings air intake port and starboard bulkheads Fan motor 1 Controls fan motor 8 In ROWPU space on port controller with bulkhead forward of door interlock Fan motor 3 Control fan motors 7, 9, and 10 1 on deckhouse starboard controllers bulkhead, 2 on deckhouse aft bulkhead Ventilation 1 Provides emergency shutdown Second button from left emergency button of all ventilating fan motors on row of seven RED buttons located starboard bulkhead aft of door Power panel 2 1 Controls ventilating system ROWPU starboard bulk- fans in voids and deckhouse head forward of sliding door Louvered air 2 Provides fresh air to voids Aft deckhouse bulkhead intake ventilation 4 for diesel engines hatches Louvered hatch 2 Provides weathertight seal on air Aft deckhouse bulkhead covers intake ventilation hatches (5) Void 2 port - ROWPU space near port bulkhead (6) Void 3 port - same as void 2 port farther aft (7) Void 4 port - same as void 3 port farther aft (8) Void 5 - overhead in void 4 port.  This is a branch from void 4 port, so dosing void 4 port also shuts off air to void 5. d. Close switchboard circuit breaker P8 to provide power to power panel 2. e. Make sure power panel 2 circuit breakers 7P8 thru 10P8 (Figure 7-3) are dosed. 7-9