rear area and intended to restore the equipment to its original clean condition. Decontamination of equipment contaminated
by NW agents should proceed with an understanding of the following basic facts:
Contamination with radioactive substances does not occur evenly. It attaches to rough and porous surfaces and those
surfaces subject to scaling or encrustation.
Some radioisotopes are more readily absorbed on surfaces than others are. Radiological contaminates (unlike chemical
or biological contaminants) cannot be inactivated, neutralized, or destroyed. No degree of heat, cold, or chemical
reaction can speed up or slow down the rate of decay. Time is the only factor that can destroy radioactivity.
Decontamination should always proceed using mild methods first and then proceed to harsher methods.
Before
proceeding with radioactive equipment decontamination, you need to establish the degree of contamination acceptable.
Often doing this is difficult because most of the contamination will be inside pipes or pumps. Positive radiation readings
outside the plumbing can be obtained only when the contaminating material is a gamma emitter. If the contaminating
material emits alpha or beta rays, the particles are often shielded by the equipment walls. In such cases, you will need to
instruct your personnel to open the equipment by loosening a union and removing a section of pipe. Then you will have
them insert a beta-gamma survey meter, such as IM-141/AN/VDR-2 radiacmeter, directly into the pipe as a probe.
During biological decontamination of a ROWPU, materials used for decontaminating the circuits of water purification
equipment contaminated with BW agents should be effective disinfectants, rapid in action, nonhazardous, noncorrosive, and
available in quantity. Although very few materials meet all these criteria, many are used in spite of certain disadvantages
such as the previously described use of calcium hypochlorite.
The basic materials used for chemical decontamination, STB and soap and water, are also effective against biological
Since most CW agents are water-soluble, the simplest and usually the most effective method of
decontaminating the water circuits of ROWPU equipment is rinsing with pure uncontaminated water. This method simply
dissolves the agent away. In addition, hydrolysis usually takes place. Soaps, detergents, and wetting agents may also be used
by way of their cleansing action. Chemical decontaminants can be used if more potent applications are needed.
Monitoring NBC Waste Disposal. Ensure that your personnel take great care in the disposal of NBC laden liquid wastes
generated by wash down of the equipment or by actual operation. These wastes can be a direct hazard to your water point
operators. This is where the three basic principles used by the commercial nuclear power industry can also be applied to the
disposal of BW and CW wastes. They are:
DI and DI - Dilute and Disperse
CO and CO - Concentrate and Confine
DE and DE - Delay and Decay
In applying these principles, you can consider one or more of the following procedures.
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