HANDLING AND STOWING CYLINDERS

It must be remembered constantly that ALL compressed gases are hazardous. Many detailed precautions could be set down with regard to the handling and stowing of these gases. The more important ones are summarized in this section.

The term slowage as used in the following paragraphs refers to articles under the control of the supply officer in general stores. They maybe articles drawn on for the ship's own use, or cargo being transported. It does not refer to cylinders that have been removed from stores or from cargo and transferred to the shops or other locations for use.

The term ready service refers to cylinders or other articles which have been transferred from stores and are actually located in a shop or near a place where they are to be used. It is not necessary that the articles be in actual use, but they must be ready for use.

Handling Cylinders

Cylinders that contain flammable and/or explosive gases must be handled with extreme care. Every effort should be made to avoid dropping them or allowing them to strike too hard against each other or any other object. Take every precaution to prevent bumping or striking the discharge valves.

When cylinders are being handled, the cylinder valve outlet cap and the cylinder valve protecting cap must be in place. Unless ready-service cylinders are secured in special portable racks, regulators must be removed and caps replaced before the cylinders are moved to a new location. Even then, it is best to remove the regulators and replace the caps for safety.

Be very careful when loading or transferring cylinders, especially when using a crane or derrick. The cylinders must be secured in a cradle, suitable platform, rack, or special container such as a sandbag. Electromagnets must never be used. A cylinder moved by hand should be tilted slightly and rolled on its bottom edge, without dragging or sliding. Hooks or lines through the valve protection cap must not be used for hoisting cylinders. Cylinders frozen to the deck, or otherwise fixed, must not be pried loose with crowbars or similar tools.

When gas cylinders are transported on a hand truck, they must be held securely in position. The truck should be fastened to a bulkhead or stanchion as soon as the destination is reached. The truck should be constructed as follows:

1. Frame sufficiently rigid to permit handling with tackle.

2. Grips or handles ending in a vertical line with the aft side of the wheels. (This facilitates fastening to a bulkhead.)

3. Platform fitted with sides to prevent the cylinders from sliding off.

4. Metal strap clamps provided for retaining the tops of the cylinders in place. Chains are not to be used as retainers since they normally are a little slack; the cylinders can shift and cause an accident.

Stowage of Compressed Gases

In general, weather-deck stowage will be provided for flammable and explosive gases. However, in specific cases, below-deck stowage is approved; depending on the particular type,

mission, and arrangement of the ship. In such cases, these approved locations are shown on the ship's plans.

Compressed gases aboard all ships, except cargo ships, should be stowed only in compartments designated by NAVSEA, as shown in applicable plans for the ship. In such cases, the following precautions must be observed:

1. Necessary steps should be taken to keep the maximum temperature of the stowage compartment below 130F.

2. When provisions are made for mechanical ventilation, this ventilation should be operated in accordance with the damage control classification assigned. The classification for closures of this system are either "Z," "W," or m

3. The installation of portable electric wiring and equipment is not permitted in compartments designated for the stowage of flammable or explosive gases.

4. Flammable materials, especially grease and oil, must be kept out of the stowage space.

5. Each cylinder must be securely fastened individually, in the vertical position (valve end up), and by such means as metal collars. Other arrangements are approved for cargo ships fitted especially for cylinder transport.

6. Oxygen and chlorine must be stowed in compartments separate from flammable gases. Inert or nonflammable gases may be stowed in any compartment designated for compressed-gas stowage.

7. Compartments containing compressed gases must be ventilated for 15 minutes before entry in the event that ventilation has been closed down. A suitable sign to this effect should be posted on the outside of the access door.

When compressed gas is stowed on the weather deck, the following additional precautions must be observed:

1. Oxygen and chlorine cylinders must not be close to the fuel-gas cylinders. Normal practice is to stow gas cylinders on one side of the ship and to stow oxygen and chlorine cylinders on the other side.

2. Cylinders containing compressed gases should be stowed for the greatest possible protection. During the winter, cylinder valves must be protected against the accumulation of snow and ice. Warm water (not boiling) should be used to thaw ice accumulations in cylinder valve caps and outlets. Boiling water may melt the fusible plugs. During the summer, cylinders must be screened from the direct rays of the sun.

3. Make every effort to prevent corrosion of threaded connections of cylinders that are stowed for extended periods of time. The use of ^{grease, lubricants,} or flammable corrosion inhibitors on oxygen cylinders is NOT permitted. Oil or grease in the presence of oxygen under pressure will ignite violently.

4. The stowage area should be as far away as practical from navigation stations, fire control stations, and gun mounts.

Ready-Service Storage Rules

1. Cylinders in actual use, and those attached to welding, fire-fighting, medical, refrigeration, or similar apparatus, ready for use, are permitted below decks outside of the stowage compartment.

2. The following special precautions must be taken with oxygen and fuel-gas cylinders for welding:

a. The number of cylinders of gas needed to equip each authorized gas cutting and welding position may be installed in shops. The number of authorized positions will be determined from either a NAVSEA-approved plan or the machinery specifications for the shop concerned.

b. Cylinders must be securely fastened in a rack. The rack must be securely fastened to the bulkhead at the designated location.

c. Cylinders attached to NAVSEAapproved damage control equipment may be stowed below decks in repair lockers. Spare cylinders used for this purpose may be stowed in the same locations.

d. Welding units maybe removed from the designated stowage location in order to perform work at some remote location in the ship. These units must be returned to the designated stowage location immediately after you complete your work. The equipment must be attended at all times while it is away from its regular stowage location.

e. A card showing the following must be posted at the designated stowage location of each unit:

WARNING

THIS UNIT IS NOT SECURE WHILE PRESSURE SHOWS ON GAGES, OR WHEN CYLINDERS ARE NOT FIRMLY FASTENED TO RACK OR TO BULKHEAD, OR WHEN RACK IS NOT FIRMLY FASTENED TO BULKHEAD. IF REMOVED FROM THIS LOCATION, THIS UNIT IS TO BE CONSTANTLY ATTENDED UNTIL RETURNED AND SECURED.

f. A card showing the following must be attached to each unit:

RETURN TO (DESIGNATED LOCA-TION) IMMEDIATELY ON COMPLE-TION OF WORK.

UNIT SHALL NOT BE LEFT UN-ATTENDED WHILE AWAY FROM ABOVE LOCATION.

UNIT IS NOT SECURE WHILE PRES-SURE SHOWS ON GAGES, OR WHEN CYLINDERS ARE NOT FIRMLY FASTENED TO RACK OR BULK-HEAD, OR WHEN RACK IS NOT FIRMLY FASTENED TO BULKHEAD OR STANCHION.

See Naval Ships' Technical Manual, chapters 550 and 074, volume 3, for detailed precautions.

3. Fire extinguishers that use gases, fireextinguishing cylinders permanently connected to fixed fire-extinguishing systems, and chemical canisters for oxygen-breathing apparatus may be stowed in the vicinity in which they would be used.

Disposition of Empty Cylinders

Empty cylinders should be delivered to the nearest naval supply depot. Valves should be closed and under some positive pressure, except where the design of the valve does not permit closing, as is the case with fire extinguishers. The pressure is necessary to prevent condensation of atmospheric moisture on the internal walls. In the case of acetylene cylinders, the pressure prevents loss of the solvent (acetone) and/or entry of air, if the cylinders cool considerably below the temperature at which they were discharged.

Sometimes, cylinders used for aviator's breathing oxygen, dry nitrogen, argon, or dry air are found to have open valves and/or a positive internal pressure of less than 25 psi. These cylinders should be tagged with the explanation that they must be dried before they are refilled.