INSTALLED CO2 SYSTEMS

Carbon dioxide extinguishers are installed in naval ships to provide a dependable and readily available means to flood (or partially flood) certain areas that present unusual fire hazards. An installed CO2 extinguishing system has one or more 50-pound cylinders. The cylinders may be installed singly or in batteries of two or more. Except for their size and releasing mechanisms, the 50-pound portable cylinders are essentially the same as the 15-pound portable cylinders.

There are two types of installed CO2 systems-the hose-and-reel installation and the flooding system. The flooding system is used for spaces that are not normally occupied by personnel.

CO2 Hose-and-Reel System

The CO2 hose-and-reel installation consists of

two cylinders, a length of special CO2 hose coiled on a reel, and a horn-shaped nonconducting nozzle equipped with a second control valve. When the hose and reel are both installed near the normal access, each of the two cylinders is provided with an individual on-off control.

(See fig. 5-42.) If the cylinders are not located near the hose reel, remote control pull boxes are provided at the hose reel for discharging each cylinder individually (fig. 5-43).

To operate a CO2 hose-and-reel system, use the following procedure:

^1. Make sure that the horn valve is in its CLOSED position.

^2. Open the control valve on the cylinder intended for use.

3. Unreel the hose and run the horn to the point of attack on the fire.

^4. Open the horn valve by turning the lever or by depressing the squeeze grip.

5. Direct the CO2 discharge toward the base of the fire, not toward the center of the fire.

CO2 Flooding System

The CO2 flooding system (fig. 5-44) consists of one or more cylinders connected by piping from the valve outlets to a manifold. Fixed piping leads from the manifold to various areas of the compartment to be flooded. Cables run from the valve control mechanisms to pull boxes that are located outside the compartment containing the cylinders. The cylinders may also be located outside the compartment to be protected. To release CO2, just break the glass in the front of the pull box and pull the handle of the cable leading to the CO2 cylinders.

There are usually one or two valve control devices in a CO2 flooding system. The number of valve control devices provided will depend on the number of cylinders in the bank. The

Figure 5-42.-Hose-and-reel CO2 installation with local control at cylinders. 5-42

Figure 5-43.-Hose-and-reel CO2 installation with remote control pull boxes.

Figure 5-44.-CO2 flooding system.

remaining cylinders in the bank (if any) are provided with pressure-actuated discharge heads. These open automatically when pressure from the controlled cylinders enters the discharge head outlet.

The CO2 installations in naval ships are made by several manufacturers, and they differ in some minor details. For detailed information on a specific installation, consult the manufacturer's technical manual.

Before operating an installed CO2 system, be sure that all openings in the compartment are closed and that the ventilation system for the space is secured. These precautions are necessary to prevent the loss of CO2.