83 mattresses of four lower bunks in the

83 mattresses of four lower bunks in the most convenient compartment provided with outboard ventilation when surfaced.

amount of heat evolved will be slight.

Consequently, when determining the warmth of the chemical by touch, care should be taken that the material is fully

b. Slit the mattress covers and spread the covers, single thickness, as smoothly and taut as possible over bunk springs. Lash the edges to the bunk spring, if necessary, to keep it taut. Remove the cover from one of the CO₂ absorbent containers and pour about one-fourth of the contents (approximately 3 1/2 pounds) on the cover. With a stick, spread the chemical as evenly as possible over the mattress covers. In pouring the chemical from the container and in spreading it on the mattress covers, care should be taken not to agitate it any more than necessary, as it is caustic and the dust will cause throat irritation. The irritation, however, is only temporary and while in many instances, coughing and sneezing may be induced, the effects are not harmful.

After working with the chemical, do not rub the eyes before the hands have been thoroughly washed. If it should get into the eyes, painful, but not dangerous, irrigation will result.

It may be relieved by washing the eyes with a solution of 1 part vinegar or lemon juice and 6 parts of water, or by careful washing with a quantity of fresh water. Do not spread the

chemical with the hands. Use a stick or other means. After spreading, stir it gently once each hour.

Under normal submerged operation conditions, the contents of one container when spread on four

mattress covers, as outline above, will absorb CO₂ for 144 man hours, or will absorb the CO₂ produced by a crew of 33 men for approximately 4 1/2 hours;

a crew of 43 men for approximately 3 1/2 hours; a crew of 87 men

spent before renewing it. If there is any doubt on this point, leave the material spread on the mattress cover and spread an additional charge on a split mattress cover in an additional bunk.

Because of the desirability of keeping the chemical from dusting as much as possible, the refilling of the mattress cover and the spreading of the chemical should not be resorted to any oftener than necessary. Accordingly, if

submergence of any particular vessel is to exceed the time of CO₂ protection afforded by the chemical in the initial container, the contents of the necessary additional container or containers should be spread out on additional mattress covers in the amount necessary to furnish the increased man hours of protection required, in the same or other convenient compartments, using

approximately 3 1/2 pounds of the chemical on each additional cover. The number of additional covers so used should depend upon the total number of men on board and the estimated total time for which protection from CO₂ must be afforded.

Higgins and Marriott carbon dioxide testing outfits are supplied for

determining the percentage of carbon dioxide in the air on submarines, and one of the outfits should be carried on each submarine. The test with this apparatus is extremely simple and sufficiently accurate for all practical purposes.

7B2. Oxygen system. Eleven oxygen standard containers are distributed throughout the compartments of the vessel, the total capacity being sufficient to supply 37 cubic feet per man of oxygen at normal temperature and

approximately 1 3/4 hours.

When this chemical absorbs CO2, it evolves heat and is warm to the touch.

The amount of heat evolved depends upon the amount of CO2 present in the air and the rate of its absorption. When the chemical no longer evolves heat in the presence of CO2, it has become saturated and should be renewed.

However, with small numbers of men in a compartment, the amount of CO2

generated will not be so great as that produced by a large number of men and the

atmospheric pressure. Two flasks are stowed in the forward torpedo room and two in the after torpedo room. Each of the other compartments, including the conning tower, has one flask. The flasks and regulator valves in the forward torpedo room, after torpedo room, and the conning tower are piped to form banks in each of the three compartments with a valve for the compartment and a manifold for escape arrangements.

84

Figure 7-5. Oxygen tank.

These manifolds, located in the forward escape trunk, conning tower, and just forward of the escape trunk in the after torpedo room, have four valves. Each valve is provided with a 6-foot length of rubber hose, fitting with a self-closing chuck of the Schrader type, for charging escape lungs.

The containers in the other rooms are fitted with the regulator valves for replacing the oxygen content of the air as desired.

The container or containers in one compartment are not connected with those in another compartment.

C. VALVES

7C1. Classifications. The ventilation system is provided with valves classified as follows:

1. Engine induction and ship's supply outboard valve. (Superstructure abaft conning tower.)

2. Engine induction hull valve.

(Forward engine room.)

3. Engine induction hull valve. (After engine room.)

4. Maneuvering room induction hull valve. (Maneuvering room.)

5. Ship's supply hull valve. (Forward engine room.)

6. Bulkhead flapper valves, supply and exhaust.

All of these valves are described separately in the following sections.

7C2. Engine induction and ship's supply outboard valve. The engine induction and ship's supply outboard valve is a 36-inch disc type valve (Figure 7-1), located in the air induction standpipe in the superstructure abaft the conning tower. (See FigureA-10.) When open, this valve permits air to enter the engine air induction and the hull ventilation supply lines; when shut, it

85

Figure 7-6 Engine induction hull valve.

86