Suit material

Along with cotton blends, polyester blends with rayon or wool are also important. Wool—polyester blends are widely used in men s suiting materials. For these fabrics, PET staple or tow can be used with a linear density typically about 0.16—0.45 tex per filament (1.5—4 dpf) and a staple length of 50—75 mm (2—3 in.). 

Equipment Suite An equipment suite is the collection of equipment available for producing a group of products. Normally, this group of products is similar in certain respects. For example, they might all be manufactured from the same major raw materials. Within the equipment suite, material transfer and metering capabilities are available for these raw materials. The equipment suite contains all of the necessary types of processing equipment (reactors, separators, and so on) reqiiired to convert the raw materials into salable products. A plant may consist of only one suite of equipment, but large plants usually contain multiple equipment suites. 

The materizils in current use have limited resistance to the broad ranges of commonly spilled chemicetl solvents. In fact, no one suit material is known to resist attack by all chemicals. Rubber or polymeric materials eire all permeable to some degree but for some chemicals, there is no acceptable gairment available to provide adequate protection for the wearer. Consequently chemiczil response teams must rely on an inventory of suits constructed of different materials to provide adequate personnel protection. 

Several standards exist or are being established to specify test methods to mezisure suit material characteristics and performance. 

An evaluation of the CST (including its effluent gas treatment system) for treatment of wood dunnage and DPE suit material indicates successful treatment of both materials. Also, the test report noted that additional design and development for the solid materials handling and gaseous effluent systems were under way as this report was being prepared. 

Preventing the segregation of the carbon-carrier medium and shredded DPE suit material and wood dunnage in the solids feed to the CST to... 

Selection of materials of construction with satisfactory corrosion resistance for the auger and air preheater—the test report indicates that the auger corrosion appears related to the chlorine contained in shredded DPE suit material (Parsons, 2001). 

The GPCR process was able to achieve 5X decontamination of carbon, PCP-spiked wood, DPE suit material, firing tubes, and HD mortar casings. However, the first run with DPE suit material was stopped prematurely because the reactor input line plugged. 

DPE suits, and butyl rubber (NRC, 2001b). The levels were 0.0002 to 0.0008 ng/m3, three orders of magnitude below the EPA criterion of 0.2 ng/m3 for dioxin emissions from incinerators. In the test with neat GB, the product gas contained 0.01 to 0.06 percent phosphine. As noted previously in the section on methods development testing, phosphine can interfere with the measurement of GB. Based on results from the EPA s toxicity characteristic leachate procedure, stabilization would be necessary only for solid wastes derived from DPE suit material, because the cadmium and lead criteria were not met by the treated dunnage in some tests (NRC, 2001b). 

The tests on DPE suit material and wood addressed size-reduction and material-transport problems identified during the Demo I testing (NRC, 2000a). DPE suit and butyl rubber simulant materials were shredded in a dedicated granulator, cryogenically cooled in a cryo-cooler with an internal screw conveyor, and reduced in a cryocooled hammer mill. No materials contaminated with agent were tested. 

In spite of a few minor operating problems, the DSHS tests appeared to have been successful. All materials, pallets, carbon, and DPE suit material were reduced to the size specified for feeding to the SCWO system the metal removal devices appear to have performed well, and fugitive dust appears to have been controlled. The size reduction of the DPE suit material was of special interest because the technology for heavy polymeric composites is comparatively new. 

It is critical that the feed to the hydropulper be reduced to a fine powder in the slurry feed stream to the SCWO reactor. Micronization of DPE suit material was successful during the EDS II testing the desired particle sizes were produced in a single pass. The technology appears to have been validated. 

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. 

Nevertheless it was not before 1949 that the most suited materials in this respect, viz. ion-exchange resins comparable with the technical ones, were successfully used in the preparation of the selective membranes (61, 68, 184). 

PHOTO 20.2 Level A Side and rear view, notice that the entire self-contained breathing apparatus (SCBA) is contained within the vapor- and liquid-proof protective suit. The suit material, zippers, and seams are made of vapor-impermeable material and construction. Level A is the only level to maintain vapor-proof integrity. (Photos 20.1 and 20.2 are courtesy of the Center for Domestic Preparedness, Department of Homeland Security, Anniston, Alabama. These images are the work of an employee of the Center for Domestic Preparedness, taken or made during the course of official duties. As a work of the U.S. Federal Government, the images are in the public domain.)... 

Each suit was evaluated for the permeation of agents through suit material and the level of protection afforded by the suit ensemble against agent vapors. Breakthrough for the permeation test was set at 200 ng/cm2 for sulfur mustard and 800 ng/cm2 for sarin. 

Permeation is essentially the movement of chemicals at the molecular level through intact suit material. It is usually expressed as breakthrough times for a given chemical or chemical class. 

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