17.14.4.1 The ship should
be provided with a chlorine absorbing plant with connections to the
cargo piping system and the cargo tanks. The absorbing plant should
be capable of neutralizing at least 2% of the total cargo capacity
at a reasonable absorption rate.
17.14.4.2 During the gas-freeing
of cargo tanks, vapours should not be discharged to the atmosphere.
17.14.4.3 A gas detecting
system should be provided capable of monitoring chlorine concentrations
of at least 1 ppm by volume. Suction points should be located:
-
.1 near the bottom of the hold spaces;
-
.2 in the pipes from the safety relief valves;
-
.3 at the outlet from the gas absorbing plant;
-
.4 at the inlet to the ventilation systems for the
accommodation, service and machinery spaces and control stations;
-
.5 on deck at the forward end, in the middle and at
the after end of the cargo area. (Only required to be used during cargo handling
and gas-freeing operations.)
The gas detection system should be provided with an audible
and visual alarm with a set point of 5 ppm.
17.14.4.4 Each cargo tank
should be fitted with a high-pressure alarm giving an audible alarm
at a pressure equal to 10.5 bar gauge.