module contains a pneumatic system, an ionization
The through-the-bulkhead unit consists of an
and detection system, and an alarm electrical system,
electronics and fan assembly. This assembly provides
which is necessary to perform the agent sampling
continuous air samples for the alarm module.
operations. The pneumatic system is used to supply air
The remote control unit connects the remote status
samples from the TBU to the alarm module for
unit with the appropriate detector and the power
chemical analysis. It will then remove the air sample
supply. The remote status unit is mounted on the ship's
once the sample has been analyzed as exhaust.
bridge but has no control over the system. It merely
The ionization and detection system draws air
reports the status of the system. However, it does have a
samples into a heater block where it is heated to a
manual override of the ship's alarm system.
temperature of approximately 140F. The sample
Since the system is automatic, it requires no
moves into a sensor cell for ionization. A sample
operation procedures once it is installed. To perform
containing chemical agents will increase the output of
maintenance on the system, follow the guidelines
the sensor cell and trigger the alarm. The alarm
listed in the planned maintenance system.
electrical system provides the power to maintain
airflow, heater temperature, and the other electrical
MONITORING OF CHEMICAL AGENT
systems involved.
CONTAMINATION
The power supply provides the input power from
In general, the purpose of chemical surveys is to
the ship's electrical system. If the input power is lost,
detect, locate, and identify chemical agents in either
the power supply provides the power from an internal
battery.
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