When bubbles appear around the valve stem and packing gland nut when a soap solution test is being made, the packing nut should be tightened or the gland packings should be replaced.

With the regulator hose disconnected, close the cylinder valve. When bubbles form at the regulator hose connection when a soap solution is applied, the valve seat is leaking. Open and close the valve quickly several times and allow pressure to blow through quickly. This procedure may clear the valve seat of dirt and correct the trouble. If the leak continues, the cylinder should be returned to the factory for test and repair.

Q27. A self-generating oxygen-breathing apparatus protects you from what type of atmospheres?

Q28. What is the last step in donning a facepiece?

Q29. Oxygen cylinders are hydrostatically tested how often?

WATER STORAGE FACILITIES

LEARNING OBJECTIVE: Identify different types of water storage facilities and their associated support equipment. Understand their operation, uses, and maintenance.

The operation of storage facilities in the distribution system is largely a matter of maintaining sufficient levels through adequate pumping and controlling water flow through appropriate valves.

Live storage, where water is constantly circulating from the supply into the distribution system, is preferred to noncirculating storage because the latter depletes the chlorine in the water and allows tastes and odors to develop. If dead storage is necessary, the operator must maintain a close watch on chlorine residuals and the development of odors and tastes, and report conditions regularly to higher authority.

TYPES OF STORAGE

Facilities for storage of water include open reservoirs, underground reservoirs, and elevated storage tanks. Ground storage reservoirs may be the same or similar to those shown in figure 8-12. Three types of elevated storage tanks, which you may find at naval activities, are pictured in figure 8-13. You may also see standpipes, like the one shown in figure 8-14, used at some activities. Standpipes are, in effect, ground level storage tanks. The distinguishing characteristic of a standpipe is its relatively small diameter and extra height to provide head pressure. Under no conditions should the amount of stored water be reduced to a point below that necessary for fire fighting. Daily records maintained by the operator help ensure against such a condition.

Pneumatic water tanks are usually found in use at smaller installations. They consist of a pressure vessel partly filled with water, and a compressor unit that supplies air pressure to produce the desired water pressure. Pneumatic tanks may be within buildings, on outside surface locations, or underground. While the operation of these units is usually automatic, the operator is responsible for the effective operating of pressure equipment. The manufacturer's instructions should be consulted for methods of starting, stopping, and operating this pressure equipment.

MAINTENANCE OF STORAGE FACILITIES

Here are the elements in the maintenance of storage facilities: the construction materials- concrete or steel; and the location of the tank-ground level, belowground, or elevated.

Foundations

All tanks have foundations of concrete, wood, or steel. Each material has its own maintenance procedures.

Concrete foundations should be inspected semiannually for settlement, cracks, spalling, and exposed reinforcing. When deterioration has set in, the foundation should be repaired with a mixture of 1 part cement to 1 part sand.

Wood foundations and pads should be inspected for split members, rot, termite infestation, and for direct soil contact of untreated wood. Any repairs necessary to remove the undesirable condition should be made.

Maintenance procedures for steel foundations are similar to those given later in this chapter for elevated storage tanks.

Concrete Storage Tanks

Concrete storage tanks may be either prestressed or nonstressed design. There is little difference in the maintenance procedures, which depend mainly on the location of the tank-aboveground or belowground.