Protective garment permeation

Testing for the presence of permeated chemical contaminants requires that pieces (in the case of contaminated soil this would be typically those that visually indicate contamination) of the protective garments be sent to a laboratory for analysis. 

Permeation of Protective Garment Materials by Liquid Halogenated Ethanes and a Polychlorinated Biphenyl... 

C. Solvent Permeation Through Protective Garment Material... 

Experiments were performed to determine the rate at which the halogenated ethanes and the PCB used in this study permeated various protective garment materials. Discrete, rather than continuous, sampling was employed for these studies and because of the hazardous nature of the compounds employed, the experiments were performed in a chemical fume hood having a face velocity >125 linear ft./min. 

Figure 1. Permeation cell used to measure protective garment material breakthrough times...

Because of their widespread use in the American workplace, butyl rubber, nitrile latex, neoprene latex, poly(vinyl alcohol), surgical rubber latex, and Viton elastomer were chosen for the present studies. The composite/bonded substances of this study were not in all cases presently available as commercial material for protective garments, but rather were chosen to determine their potential for resistance to solvent permeation. Likewise, Teflon gloves were included in these studies simply because they are commercially available. 

Most of the homogeneous, nonbonded protective garment materials chosen for these studies were obtained from commercial sources and were thus representative of materials available to workers in the U.S. The composite materials were not generally used as glove materials, but rather were chosen as being representative of material available for use in coats or aprons or were experimental or prototype materials. In the present work, the results of these permeation studies are presented in three ways ... 

Protective Garment Materials Permeation by Halogenated Ethanes (1,2-Dichloroethane 1,1,1-Tricloroethane and 1.1,2-Trichloroethane). Tables IV, V, and VI present the protective garment breakthrough times for 1,2-dichloroethane 1,1,1-trichloro-ethane and 1,1,2-trichloroethane for both the homogeneous, non-bonded materials and for the coated/bonded composite materials. 

DICHLOROETHANE PERMEATION RATE PROPERTIES OF PROTECTIVE GARMENT MATERIALS... 

Glove Selection. The proper selection of gloves or other protective garments that act as a barrier against direct physical contact with the skin or other body surfaces is made difficult by the wide range of hazardous chemicals encountered in semiconductor processing. The prevalence of mixtures of chemicals and manufacturing specific formulations whose permeation characteristics are usually not scientifically tested or published, and based only on empirical data from actual use in the industry. 

Ihe asteridc denotes a warning flag shewing that the permeation rate, which is unknown, was not used in the expert decision module, so the Estimated Protection Time of the garment is possibly hi. ... 

Compatibility Charts Permeation and penetration data supplied by the manufacturers of protective clothing to indicate chemical resistance and breakthrough time of various garment materials as tested against a battery of chemicals. 

Of the remaining materials in Table IV, only Viton, neoprene rubber latex,poly(vinyl alcohol), butyl rubber, and butyl-coated nylon exhibited at least a 20-min breakthrough time forl,2 dichloro-ethane permeation to occur. The nitrile rubber latex, cement dipped nitrile rubber, polyethylene (medium density), and surgical rubber latex were all penetrated by 1,2-dichloroethane in less than 3 min and would be of little use in situations requiring the garment to be in constant contact with 1,2-dichloroethane. From the above, butyl rubber or Viton appear to be the best materials to protect the worker against 1,2-dichloroethane, but because of apparent lot-to-lot variations(20) in butyl properties, Viton appears to be the best suited material of these studies to protect the worker from this chemical. 

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