§154.345. Air locks.
46 C.F.R. § 154.345
An air lock may be used for access from a gas-dangerous zone on the weather deck to a gas-safe space.
Each air lock must—
Consist of two steel doors, at least 1.5 m (4.9 ft.) but not more than 2.5 m (8.2 ft.) apart, each gasketed and tight when tested with a fire hose at not less 207 kPa gauge (30 psig);
Have self-closing doors with no latches or other devices for holding them open;
Have an audible and visual alarm on both sides which are actuated when both door securing devices are in other than the fully closed position at the same time;
Have mechanical ventilation in the space between the doors from a gas-safe area;
Have a pressure greater than that of the gas-dangerous area on the weather deck;
Have the rate of air change in the space between the doors of at least 8 changes per hour; and
Have the space between the doors monitored for cargo vapor leaks under § 154.1350.
In addition to the requirements of paragraphs (a) and (b) of this section, no gas-safe space on a liquefied flammable gas carrier may have an air lock unless the space:
Is mechanically ventilated to make the pressure in the space greater than that in the air lock; and
Has a means of automatically de-energizing all electrical equipment that is not explosion-proof in the space when the pressure in the space falls to or below the pressure in the air lock.
Notes, amendments, and revision history
Authority
Authority: 46 U.S.C. 3703, 9101; Department of Homeland Security Delegation No. 0170.1.
Source
Source: CGD 74-289, 44 FR 26009, May 3, 1979, unless otherwise noted.