Decontamination methods

We do not attempt to discuss in depth decontamination methods for radiological wastes. A health physicist should be immediately available to assist with decontamination of radioactively contaminated personnel or equipment. 

Specific decontamination methods that will be used, including specific instruments such as brushes that will be used along with detergents or fluids for neutralization... 

Appropriate decontamination methods (high-pressure wash)... 

To prevent the further generation of mixed wastes, decontamination methods should be chosen carefully and implemented to be part of the overall solutions and not part of the cleanup [2]. 

Contractors at Sites C and H had acceptable programs for monitoring the effectiveness of PPE and decontamination procedures. The Site H contractor had established PPE and decontamination programs consistent with HAZWOPER requirements. The Site C contractor developed decontamination procedures that included specifications for periodically evaluating the effectiveness of decontamination methods... 

Delineation of these three zones should be based on sampling and monitoring results and on an evaluation of the potential routes and amount of contaminant dispersion in the event of a release. Movement of personnel and equipment among these zones should be minimized and restricted to specific access control points to prevent cross-contamination from contaminated areas to clean areas. A decision for evaluating health and safety aspects of decontamination methods is presented in Figure 16.22.105... 

Although decontamination is performed to protect health and safety, it can pose hazards under certain circumstances. Decontamination methods may have the following characteristics ... 

They may be incompatible with the hazardous substances being removed (i.e., a decontamination method may react with contaminants to produce an explosion, heat, or toxic products)... 

The chemical and physical compatibility of decontamination solutions or other decontamination materials must be determined before use. Any decontamination method that permeates, degrades, damages, or otherwise impairs the functioning of the personal protective equipment (PPE) is incompatible with such PPE and should not be used. If a decontamination method does pose a direct health hazard, measures must be taken to protect both decontamination personnel and the workers being decontaminated. Figure 16.22 presents a decision aid for the evaluation of health and safety aspects of decontamination methods. 

High hydrostatic pressure (HHP) and pulsed electric fields (PEFs) are rather novel technologies where relatively little research has been carried out. These methods have mostly been tested in combination with other decontamination methods and also mostly on either microorganisms in vitro or on foods of animal origin (e.g. milk, eggs and meat) (Raso and Barbosa-Canovas, 2003 Ross et al., 2003). More research is needed in order to find out if such methods are applicable to the fresh produce industry. 

Several decontamination methods exist, but the most versatile treatment among them is processing with ionizing radiation. Decontamination of food by ionizing radiation is a safe, efficient, environmentally clean, and energy-efficient process. Shelf-life... 

Personnel decontamination methods to be administered prior to medical treatment... 

Treatment — Patients should be decontaminated immediately prior to treatment using the decontamination method presented in Section 7.3.2. No antidotes are known. Treatment consists of symptomatic management of lesions. If a patient inhaled HD but does not display symptoms of an impacted airway, it may still be appropriate to intubate him because laryngeal spasms or edema may make it difficult or impossible later.2... 

Treatment—Patients should be decontaminated immediately prior to treatment using the chemical agent decontamination method presented in Section 7.3.2. No known antidote is available. 

Moving away from the site of the attack as quickly as possible will reduce the amount of exposure. Orderly retreat will reduce the risk of other accidents such as sprains or broken bones. An individual could receive additional exposure for every minute spent in the open near the attack site. If he has had direct contact with a hazardous substance, the time of exposure should be minimized. Hazardous substances on the skin, clothing, and hair should be removed as quickly as possible using specific decontamination methods outlined in Chapter 7. Special medical attention should be administered as soon as possible if an individual has ingested or inhaled a hazardous substance or if the hazardous substance entered the body through a wound. Consider the following example ... 

If personnel have been exposed to blood agents (AC, CK, and SA) or choking agents (chlorine, CG, or DP), the following decontamination method is recommended prior to treatment ... 

The Department of Defense memo may still have been too highly classified, leading to inadvertent violation of its rales. One example of a violation was the Top Hat program in which volunteers tested decontamination methods for various toxic substances. The authors observe that those operating under this protocol may have thought this study was not subject to the above policies. 

Lynntech, Inc. s (Lynntech s), electrokinetic remediation of contaminated soil technology is an in situ soil decontamination method that uses an electric current to transport soil contaminants. According to Lynntech, this technology uses both direct current (DC) and alternating current (AC) electrokinetic techniques (dielectrophoresis) to decontaminate soil containing heavy metals and organic contaminants. A non homogeneous electric field is applied between electrodes positioned in the soil. The field induces electrokinetic processes that cause the controlled, horizontal, and/or vertical removal of contaminants from soils of variable hydraulic permeabilities and moisture contents. 

According to the developer, antomation is the major advantage of the SGS, affording a higher degree of accuracy in comparison to mannal methods. Another advantage of the SGS is that it can be coupled as a pretreatment with secondary downstream decontamination methods to affect further volume reduction. 

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