ENVIRONMENTAL CONTROL SYSTEMS

Magazines are fitted with environmental control and safety features to protect ammunition from excessive temperatures and humidity. Most magazines have either mechanical cooling or ventilation systems. However, there are a few magazines that don't have either of these features. If a magazine without controls shows a heat gain in excess of 100F, use portable ventilation systems to prevent overheating or condensation of moisture.

Supply and Exhaust Ventilation

Ventilation ducts and exhaust ventilation outlets to and from magazines provide forced-air ventilation, Air is forced through the ducts by electric fans installed within the duct work. Standard covers maintain watertightness and prevent the entrance of flames from hits on the ship during combat. Always close these covers during combat (general quarters) conditions, unless otherwise directed. If you inhale fumes from some types of ammunition, you might get slightly intoxicated. However, this should not appreciably reduce your work efficiency. Generally, there is sufficient air volume in large, sealed magazines and handling rooms to provide a safe working atmosphere for approximately 5 hours. Magazines that are continuously occupied by personnel are blown through or ventilated a minimum of once every 5 hours.

Magazine Vent Check Valves

Sometimes, it is necessary to operate the sprinkler system in magazines while the ventilation valves are secured When this happens, the magazine must be vented by an air escape to ensure that the pressure within the magazine doesn't build up beyond the allowed pressure limits of its watertight boundaries. Magazine check valves allow air and water to escape from the magazine into one of the ventilation ducts or through an independent air escape.

Exhaust Vents

Aboard ship, most magazines, particularly missile magazines, are vented to the atmosphere. When missile motors burn, they rapidly produce large volumes of smoke and gas. To avoid spreading smoke and gas to other areas of the ship if a missile motor in a magazine accidentally ignites, the exhaust ducts are vented to the ^atmosphere. The area on the weather deck in the vicinity of an exhaust vent is potentially hazardous, and it is marked to warn personnel not to loiter (hang around) in this area.