Polychlorinated biphenyls (PCBs) are toxic chemicals of the chlorinated hydrocarbon group. They range in form and appearance from oily liquids, to crystalline solids, to hard transparent resins. These chemicals exhibit many favorable physical and chemical properties, including high heat capacity, chemical stability, noncorrosivity to metals, low flammability, low vapor pressure, and low electrical conductivity. Therefore, they are used extensively as insulators and coolants in electrical equipment.

PCBs in use aboard ship typically function as insulating fluids or coolants in electrical equipment. (The chemicals might occasionally be found in totally enclosed hydraulic and heat transfer systems.)

Remember, these chemicals are toxic. That means they can be harmful to your health (perhaps deadly.) Their adverse effects can result from either brief or repeated exposure. The effects from short-term contact with high concentrations of PCB vapors or liquids include eye, nose, and throat irritation; headaches; and the skin rash chloracne. Repeated exposure can result in severe skin irritation, respiratory irritation, digestive tract damage, and liver damage. Systemic intoxication (an adverse effect to your entire bodily system) can result from severe overexposure. It is indicated by nausea, vomiting, weight loss, jaundice, and abdominal pain. It can be fatal.

To protect personnel, use the label shown in figure 4-4 to mark all equipment and cabinets containing in-service small and large PCB capacitors. You can find additional information on PCBs in the Shipboard Management Guide for Polychlorinated Biphenyls (PCBs), NAVSEA S9593-Al-MAN-010. We highly recommended that you study this publication.

BATTERIES

A battery is a group of cells that provide direct-current (dc) electrical power. Batteries are used in automobiles, boats, aircraft, ships, submarines, lighting equipment, and portable and stationary electrical and electronic equipment. They can be used as main power sources or as secondary or backup power sources. Some batteries are rechargeable.

Figure 4-4.-EPA-require labels for PCB hazards.

Batteries can be dangerous. If used or handled improperly, they can explode, release toxic gases, or leak hazardous chemicals.

The following section will give you the safety precautions for some of the more common types, such as carbon-zinc dry cell batteries, manganese-dioxide alkaline-zinc cell batteries, lithium cell batteries, and nickel-cadmium cell batteries.

Carbon-Zinc Dry Cell Battery

The carbon-zinc dry cell battery is a very common battery in the Navy. It has a zinc outer container, a carbon center electrode, and a chemical paste for the electrolyte. It is usually sealed in a cardboard or plastic casing.

When you use, store, or dispose of carbon-zinc batteries, always observe the following safety precautions:

NEVER store carbon-zinc batteries in electronic equipment for extended periods. The corrosive electrolyte could leak out of the battery and damage the equipment.

NEVER throw carbon-zinc batteries into afire or an incinerator. They could explode.

NEVER throw carbon-zinc batteries overboard while at sea; they contain metal pollutants. Store them on board (in a plastic-lined metal container) until you can properly dispose of them ashore. Seethe Environmental and Natural Resources Program Manual, OPNAVINST 5090.1 (Series) Appendix L.

Manganese-Dioxide Alkaline-Zinc Cell Battery

Commonly called an alkaline battery, the manganese-dioxide alkaline-zinc cell battery is similar to the carbon-zinc battery. The only difference is the type of electrolyte used. These batteries are used in portable electronic equipment. The safety precautions for alkaline batteries are identical to those for carbon-zinc batteries.

Lithium Cell Battery

The lithium cell battery is a high-energy, long lasting battery with a longer shelf life than most other batteries. It is often used in electronic equipment, such as computers, communications and cryptographic equipment, torpedoes, and missiles. Unfortunately, lithium batteries can be very dangerous. They can release toxic gases or explode. If you handle lithium batteries, observe the following safety precautions to prevent injuring yourself and damaging your equipment:

Use only lithium batteries that are approved for use in your equipment.

Store lithium batteries in cool, well-ventilated areas away from flammable items.

Always observe polarity when you install lithium batteries.

NEVER pierce, short-circuit, recharge, crush, cut, burn, drop, dismantle, modify, or otherwise carelessly handle lithium batteries.

NEVER leave lithium batteries in equipment that will not be used for long periods of time. NEVER throw lithium batteries in daily trash. Dispose of them properly. See the Environmental and Natural Resources Program Manual, OPNAVINST 5090.1, for more disposal information on lithium batteries. Nickel-Cadmium Cell Battery

Commonly known as a NICAD, the nickel-cadmium battery is used in most cordless, rechargeable equipment, such as flashlights, cordless drills, soldering irons, and portable stereos.

The following safety precautions for NICADs are relatively simple:

Charge NICADs in series, never in parallel.

Follow the manufacturer's instructions for charging NICADs.

NEVER expose NICADs to temperatures over 113 degrees Fahrenheit (45 degrees Celsius).

NEVER short-circuit NICADs.

NEVER store NICADs and lead-acid batteries in the same container or in the same area.

NEVER dispose of by throwing them overboard. Store exhausted cells temporarily in a plastic-lined steel container until you can dispose of them properly ashore. See the Environmental and Natural Resources Program Manual, OPNAVINST 5090.1 (Series) Appendix L.