Decontamination fabrics Surface

Effect of the Average Pore Size on the Adsorption Capacity and Off-Gassing Characteristics of Activated Carbon Fabrics for Decontamination of Surfaces... 

Most surface contamination is detected and removed by accepted decontamination practices. If a contaminant has permeated the PPE (i.e., the fabric of coveralls), it may be difficult to detect and remove. Wlien contaminants are allowed to remain in contact with materials for an extended period, those materials are prone to permeation or degradation [2]. 

Construction materials must be nonabsorbent and easily cleaned or decontaminated. Seamless flooring avoids cracks from which spilled chemicals can contribute a significant pollution burden to the laboratory air. Epoxy paint should be used for interior walls. Dropped ceilings should be made of nonabsorbent material such as enameled metal. Hoods and sinks should be fabricated of stainless steel. Wood or other porous surfaces must be avoided. 

Photocatalytic bactericidal activity experiments were performed using E. coli with untreated and TiO -coated fabric and aluminum foil (Fig. 1.6) and with or without UV-A irradiation. Photocatalytic bactericidal properties of TiO -coated fabric and foil were observed after 30 min. The most distinctive difference between coated and UV-irradiated materials was observed initially. This is a clear demonstration of the photocatalytic ability of TiO and accelerated surface decontamination. We observed complete bacteria killing only on aluminum foil coated with TiO, and partial killing on the coated fabric. These results suggest that TiO coated materials have bactericidal properties. 

For decontamination of fabric clothing or equipment, a 5% hypochlorite solution should be used. For decontamination of equipment, a contact time of 30 minutes prior to normal cleaning is required. Use of hypochlorite solution in this way is corrosive to most metals and injurious to most fabrics, so they should be rinsed thoroughly and metal surfaces should be oiled after completion. 

As compared to non-adsorbent fabrics that could also be used to remove hazardous liquids contaminants from solid surfaces, the adsorptive properties of the activated carbon fabrics mitigates off-gassing from used wipes. When the used wipes are repackaged in a sealable hermetic envelope, the adsorptive properties provide a redimdant means of agent isolation. The used wipes can thus be safely handled imtil they are destroyed, for example, by incineration, or decontaminated by standard means, such as immersion in bleach solution. 

For CEES loadings greater than the pore capacity for CEES, the level of CEES off-gassing from an activated carbon fabric, the level of CEES offgassing from the fabrics varies as a function of the CEES load per unit surface area of the fabric, for both microporous and mesoporous fabrics. At comparable CEES loadings, there is significantly less CEES off-gassing from activated carbon fabrics than from the M 100 powder used in the M 295 decontamination kit. This is a result of the much lower specific surface area of this powder. 

The development of materials that can withstand decontamination processes, or even selfdecontaminate (e.g., paint or fabric embedded with neutralizing additives), is needed for warfighting and support equipment. Such materials w ould survive, with full functionality, a standard low-cost decontamination process or would not need to be decontaminated at all. Resilience is especially important for high-value, sophisticated equipment such as electronics in aircrafts, or for porous materials, such as painted surfaces or seat cushions, that are quite difficult to effectively decontaminate. 

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