Safety Decontamination

At 70—140°C, peroxide is vaporised. Peroxide vapor has been reported to rapidly inactivate pathogenic bacteria, yeast, and bacterial spores in very low concentrations (133). Experiments using peroxide vapor for space decontamination of rooms and biologic safety cabinets hold promise (134). The use of peroxide vapor and a plasma generated by radio frequency energy releasing free radicals, ions, excited atoms, and excited molecules in a sterilising chamber has been patented (135). 

Effective planning is again the key. We need to keep in mind that proper decontamination can be costly, but improper decontamination can be even more costly. One large but variable cost is the time it takes workers to decontaminate. The time that decontamination will take should be estimated and incorporated into the budget. In addition, contamination control and decontamination strategies and procedures should be outlined in the safety plan, communicated to workers, and implemented before any worker enters any area where there is a potential to become contaminated. 

The safety plan should specify the level of decontamination necessary for specific site activities. Appropriate procedures should be developed and implemented to help minimize contamination, to prevent the spread, and to decontaminate workers and equipment when they exit any contaminated area [1]. 

A JHA should be conducted and hazards associated with the decontamination process should be identified to determine the appropriate types of PPE for decontamination workers. This information should be incorporated in the safety plan. 

The hazardous waste standard requires employers to make certain that when showers are a necessary step in the decontamination process, their employees shower at the end of their work shift and when leaving the hazardous waste site. Sanitation-related showers (unlike decontamination showers) are understood to be voluntary. Decontamination and emergency showers should be located close to the worksite. Sanitary showers may be located at some distance from the worksite. A statement in the safety plan encouraging good personal hygiene and daily showers is a good idea. In addition, workers should be encouraged to shower daily even if no shower is available at the worksite. 

The contractor s SSAHP for Site C contained task- and operation-specific hazard analyses and safety and health procedures that covered general operations, but they were not specific enough for prescribing control methods and PPE for each job task. The plan identified some safety hazards for each operation but did not describe SOPs for protecting employees from these hazards. The SSAHP did, however, contain personnel and equipment decontamination procedures used at the site. 

The bench where decontamination took place was only a few feet from the thermal unit and was not isolated from exclusion zone activities employees moved freely between their work stations in the exclusion zone and the decontamination bench. In addition, the subcontractor did not conduct monitoring activities to support work zone designations. Neither Site K contractor used warning signs to delineate exclusion zones, as required by their respective health and safety plans. 

Clean up in such a way tliat the hazardous material is removed and does not produce a future danger. It may be necessary to pump out a hazardous liquid or to remove contaminated soil, etc. Decontamination procedures may be necessaiy. See EPA s Standard Operating Safety Guides for instructions for decontamination required following exposure to different danger levels of liazmds... 

Chemical Stability and Decontamination. The stability of the brevetoxins is of great interest from the standpoints of detection, metabolism, and safety. PbTx-2 and PbTx-3 have been investigated in our laboratories in order to design rational safety... 

Advisory Committee on Dangerous Pattiogens (ACDP) (1990) HIV—The Causative Agent of AIDS and Related Conditions. Second revision of guidelines. London Heallh and Safety Executive. Anon ( 99 ) Decontamination of Equipment, Linen or other Surfaces Contaminated with Hepatitis B and/or Human Immunodeficiency Viruses. Depaittnent of Healtti HC 33. 

Other applications of filters include sterilization of venting or displacement air in tissue and microbiological culture (carbon filters and hydrophobic membrane filters) decontamination of air in mechanical ventilators (glass fibre filters) treatment of exhausted air ftom microbiological safety cabinets (HEPA filters) and the clarification and sterilization of medical gases (glass wool depth filters and hydrophobic membrane filters). 

Broadly speaking, the most important factors in the safe use of economic poisons are adequate information and appropriate care by all persons having any contact whatsoever with the poisons. Safety may be promoted but not ensured by voluntary control, such as the self-discipline of industry by legal control, such as regulation of sale, labeling, and distribution and by economic control, such as the refusal of food processors to buy from farmers or dealers food containing excessive residues for which no adequate method of decontamination is known. 

REMEDIATION, DECONTAMINATION, AND SAFETY MANAGEMENT 16.9.1 Site Preparation and Work Zones... 

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 ... 

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. 

FIGURE 16.22 Decision aid for evaluating health and safety aspects of decontamination. 

The impact of the decontamination process and compounds on worker safety and health... 

A publication summarises all the then available technical evidence related to the Seveso accident, and recommends operational criteria to ensure safety in commercial processes to produce trichlorophenol [4], All the plant scale incidents were characterised [ 1 ] by the subsequent occurrence of chloracne arising from the extremely toxic and dermatitic compound 2,3,7,8-tetrachlorodibenzodioxin (structure IX, p. S-3), formed dining the thermal runaway reaction and dispersed in the ensuing explosion. It is also extremely resistant to normal chemical decontamination procedures, and after the 1968 explosion, further cases occurred after transient contact with plant... 

Beuchat, L.R. (1998) Surface Decontamination of Fruits and Vegetables Eaten Raw A review. WHO, Food Safety Unit. WHO/FSF/FaS/98-2. www.who.int/foodsafety/publications/fs management/surfac decon/en/... 

Betts, G. and Everis, L. (2005) Alternatives to hypochlorite washing systems for the decontamination of fresh fruit and vegetables , in Jongen, W. Improving the Safety of Fresh Fruit and Vegetables, Woodhead Publishing, Cambridge, 352-372. 

The Army terminology for destruction of obsolete weapons Is "demilitarization". This term encompasses all the steps required to disassemble and safely destroy or decontaminate the component materials of which the munition was constructed. National Academy of Sciences and Department of the Army Guidance for demilitarization of obsolete chemical weapons (t) requires absolute safety and security, assurance of total containment of agent during processing, maximum protection of operating personnel and Incontrovertible evidence verifying the destruction of the toxic wastes. 

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