bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance Evaluation of Chain Saw Protective Leggings
Authors: Arteau J , Turcot D
Published: February 2009

The Standardization Office of Quebec mandated us to develop a test that could rate protective pads or leggings in terms of performance.

In the test, a chain saw was mounted on a horizontal axis about which it was allowed to rotate freely. A test consisted of letting the blade of this chain saw drop perpendicularly to the longitudinal axis of the legging that was mounted on a wood cylinder to simulate the leg of the worker. The legging was fixed on the specimen support in such a way that the textile threads could be pulled out by the chain so as to cause minimum interference with the protective mechanism of the textile. Wires on the legging and underneath the pad and an appropriate data acquisition system permitted measurement of the cut-through time and the chain saw speed.

The number of plies, the material thickness, and the chain saw speed were shown to change the cut-through time and stopping speed, which measures the maximum speed that the chain saw can run without actually cutting completely through the leggings.

For the first time, both performance criteria were measured with the same apparatus on the same type of leggings to confirm that these two different performance criteria were required to rate legging performance when no correction is made to the cut-through time for the free-fall time. The threshold stopping speed seems to be a preferable criterion.

The cut-through time was shown to be sensitive to the thickness of the material; the threshold stopping speed, to the strength of the assembly of fabric layers. Observations with a high-speed video camera (2000 frames/s) demonstrated the slowing of the chain by the fabrics, the stretching of the yarns up to the stitching on the perimeter of the pad, and the absence of bouncing during testing.
Dose Response of Skin Absorption in Young and Adult Rats
Authors: Hall LL , Fisher HL , Sumler MR , Monroe RJ , Chernoff N , Shah PV
Published: February 2009

The effect of skin dosage on percutaneous absorption was determined in young and adult rats using 14 pesticidal chemicals. Young (33-day old) and adult (82-day old) female Fischer 344 rats, with previously clipped mid-dorsal skin, were treated with three dosages of labeled pesticides in acetone and sacrificed 72 h following application. The treated area was 2.3% of the body surface area and was protected by a perforated plastic blister. Skin penetration was determined by dividing the radioactivity in the body plus excreta by the total radioactivity recovered. The dosages used were 0.02 to 0.35, 0.54, and 2.68 µmol/cm2 for the low, medium, and high dosage levels, respectively.

Skin penetration of the pesticides in young animals ranged from 2.9 to 81.5%, 2.0 to 84.4%, and 0.9 to 90.1% at the low, medium, and high dosage levels, respectively. In the adult, it ranged from 7.7 to 86.4%, 2.7 to 90.5%, and 1.0 to 93.3% at the low, medium, and high dosage levels, respectively.

Chlorpyrifos, dinoseb, mono- and disodium methanearsonate did not show a significant effect of dosage on dermal penetration. Dinoseb, mono- and disodium methanearsonate displayed constant fractional penetration in both young and adult animals over the dosage range examined. The other compounds showed dose-dependent dermal absorption although the total amount absorbed usually increased with dose. Dose-response curves for young and adult animals were not parallel in 8 of the 14 pesticides studied.

Eleven of the 14 pesticides showed significant age-dependent differences in skin penetration. Four of these eleven compounds had greater absorption in the young than adult at some dose. The highest and lowest significant young/adult penetration ratios were 1.53 and 0.19, respectively.

In summary, dermal absorption of the majority of the pesticides studied was found to be dependent on dose and age of the animal. With this heterogeneous group of chemicals, the correlation between skin penetration and octanol/water partition coefficients was marginal. Stratum corneum thickness did not appear to be a factor in the penetration differences between young and adult.
Permeation of Polymeric Materials by Chemicals: A Comparison of 25-mm and 51-mm ASTM Cells
Authors: Vahdat N
Published: February 2009

Chemical permeation measurements were made for six chemical/polymer systems using the 51-mm (2-in.) ASTM cell and the smaller version of the cell (25 mm [1 in.]), and the results were compared. An open loop system with gas flow rates of 1000 mL/min (33.8 fl oz/min) (ASTM cell) and 250 mL/min (8.45 fl oz/min) [25 mm (1 in.) cell] was used to determine the breakthrough times and steady-state permeation rates. For each material/chemical pair, at least four experiments were conducted in each cell. The 25-mm (1-in.) cell, compared with the ASTM cell, showed a longer breakthrough time and a lower permeation rate. However, statistical treatment of the results demonstrated that the variation of break-through times and permeation rates between the two cells was insignificant and that the two cells were equivalent.
Effect of Temperature, Material Thickness, and Experimental Apparatus on Permeation Measurement
Authors: Billing CB , Bentz AP
Published: February 2009

Despite the use of a standard test method, variations in experimental conditions make comparison of permeation results difficult. Studies which quantify the effect of several variables on chemical permeation and its measurement were conducted in order to improve the interpretation of permeation test results. The variables studied included temperature, material thickness, experimental setup (cell size, open versus closed loop), and detector sensitivity. Both theoretical and experimental approaches were taken. Fickian diffusion principles were used to characterize permeation mathematically and model the effect of the above variables. Permeation experiments were conducted for several material/chemical combinations using different-sized permeation cells and several cell temperatures. Also, permeation through several thicknesses of fluorinated ethylene-propylene [FEP (Teflon)] was measured. The 2.5-cm-diameter (1-in.) ASTM-type cell provided greater precision than the standard 5-cm (2-in.) cell, but with longer breakthrough times. Breakthrough times were seen to be profoundly affected by temperature, material thickness, and detector sensitivity.
Comparative Evaluation of a Smaller Version of the ASTM Permeation Test Cell Versus the Standard Cell
Authors: Henry NW
Published: February 2009

An evaluation of a smaller version of the ASTM permeation test cell used in ASTM Test Method For Resistance of Protective Clothing Materials to Permeation by Liquids and Gases (F 739–85) was conducted. The smaller test cell was tested using acetone as the challenge liquid chemical and milled neoprene as the test material. The tests were performed using both air (in open-loop mode) and water (in closed-loop mode) as collection media. Results of measurements of both breakthrough time and permeation rate were compared to those obtained using the larger ASTM permeation test cell. Based on statistical evaluation by two-way analysis of variance, the small test cell gave results that were not significantly different at the 5% level from the large ASTM cell.
Problems in Determining Permeation Cell Equivalency
Authors: Patton GL , Conoley M , Keith LH
Published: February 2009

Permeation tests were conducted to determine if an alternate 1-in. stainless steel cell was equivalent to the ASTM standard 2-in. glass cell. Permeation tests were conducted according to ASTM Test Method for Resistance of Protective Clothing Materials to Permeation by Liquids or Gases (F 739-85). Sheet stock neoprene (0.41 and 0.81 mm) and sheet stock nitrile (0.41 mm) were challenged with n-hexane (99%). Seven replicates of each chemical/material were tested for each cell.

Data sets of breakthrough time and permeation rate were compared using a proposed ASTM Cell Equivalency Method, Standard Practice for Determining Equivalency of Optional Chemical Permeation Test Cells to that of the ASTM Cell—Draft, 10 April 1985. This method first determines the equivalence of cells in terms of precision, via an F statistic. Equivalence in accuracy (bias relative to the ASTM cell), is then determined via a comparison of absolute percent difference and a calculated t statistic.

Analysis of ASTM and alternate cell data demonstrated standard deviations were dependent on mean breakthrough times and mean permeation rates. Therefore, the proposed ASTM procedure utilizing pooled standard deviations could not be used to determine cell equivalency. Further test results to characterize both cells are presented along with alternative statistical methods to evaluate data in cell validation tests.
An Analytical Technique for Permeation Testing of Compounds with Low Volatility and Water Solubility
Authors: Spence MW
Published: February 2009

One of the most challenging problems currently facing researchers in the field of chemical protective clothing (CPC) permeation testing is how to perform tests for compounds that have low volatility and low water solubility. Permeation testing with these compounds is difficult because an inert gas or water are currently the only permeant collection media that one can use with the assurance that the CPC material will be unaffected by the collection medium.

An approach to solving this problem using an automated sample concentrating technique in conjunction with gas chromatography is described. Such a technique allows determinations of breakthrough times and permeation rates while maintaining the permeant concentration in the collection medium at very low levels through the use of relatively high collection medium flow rates. By keeping the permeant concentration low enough to remain within the volatility limit of the compound being tested, the range of compounds that can be tested using air or nitrogen as the collection medium is greatly expanded.
Problems in Personal Protective Equipment Selection
Authors: Eiser DN
Published: February 2009

The development and validation of protective clothing test methods are very important to industrial hygiene practitioners. These methods will eventually help to ensure that protective clothing performance data are comparable, meaningful, and available to field personnel. However, field problems are typically very complex, with multiple challenges placed on protective clothing, as well as the users. The “perfect” protective clothing item is rarely, if ever, found in practice.

Protective clothing challenges can often include combinations of heat, tear, and cut hazards, rough surfaces, puncture hazards, and complex chemical mixtures. Fitting problems, differences in performance of similarly-described clothing from different manufacturers, and occasional poor quality control can cause additional complications for users. Training in the proper wearing of clothing, whether or not the equipment is considered disposable, worker acceptance, comfort, flexibility, compatibility with the work being done, and other more subtle issues also influence whether or not clothing is actually used. Dermatitis aggravated by personal protective equipment use, skin cleaners, and hand creams can also present problems to clothing users. In addition, practical guidelines for assessing toxic risks from dermal exposures to chemical agents are critical if we are to meaningfully apply protective clothing performance data.

This paper presents some of the factors that must be considered during personal protective equipment selection, and gives specific examples of typical selection problems. Engineering, job layout, and skills' training solutions are needed to minimize the need for personal protective equipment and to ensure effective use when it must be specified for protection.
Selected Protective Clothing for Semiconductor Manufacture
Authors: Gittelman DH
Published: February 2009

State-of-the-art technologies in the semiconductor industry require exotic processing techniques using unusual, hazardous chemicals. The very nature of some of these chamicals makes it necessary to very carefully select protective clothing to assure the protection of the worker.

Selection techniques are described for safety glasses, side shields, goggles, visitors' goggles, face shields; ear protection; respirators, in-line air breathing equipment, self-contained breathing apparatus; gloves—acid, solvent and heat-resistant as well as disposable types; oversleeves; aprons; head protection; footwear; and protective suits. Properties of materials—strength, permeability, durability, and impact resistance as well as chemical resistance—must be considered. Finally, recommendations for personal protective equipment to be used in the semiconductor industry are offered. Included will be an overall list of suggested equipment and possible suppliers.
Protective Clothing Materials: Chemical Contamination and Decontamination Concerns and Possible Solutions
Authors: Garland CE , Torrence AM
Published: February 2009

The theory that supports permeation testing indicates that contaminants will saturate a protective material given sufficient exposure. Once the challenge is removed, chemicals within the matrix diffuse out in both directions. The purpose of this study was to develop a method of measuring contamination of protective clothing materials and to investigate solutions to the problem of matrix contamination and release. Experimental procedures used provided the basis for the ASTM standard development in this area.

Experiments consisted of challenging neoprene, Viton, and butyl with nirobenzene. Percent contamination was measured as a percent by weight of the virgin material at several time intervals up to saturation. Up to 46% contamination was detected.

Three possible solutions to the problem of contamination were investigated: decontamination between wearings, materials with very long breakthrough times, and disposable protective clothing. Disposable protective clothing appears to be the most practical solution at the present time.

Decontamination using solvent flushing (Freon 113) was not effective even after two washes. The data generated also indicated that chemical exposure can alter the barrier properties of the material. Thermal decontamination proved effective with nitrobenzine and neoprene, but more research is needed to determine the extent to which it can be applied. Teflon-coated Nomex, which has a long breakthrough time, exhibited no detectable matrix contamination. As expected, contamination was found to be inversely related to breakthrough time. Where exposure times are very small fractions of breakthrough time, it may be possible to decontaminate by surface cleaning. Disposable protective clothing of laminated Tyvek offers excellent barrier properties to many chemicals. With disposable clothing worn by itself or over a reusable clothing, the contamination problem is discarded with the contaminated garment.
Skin Protection and Sensitizing Epoxy Compounds in Electron Microscopy Laboratories
Authors: Jolanki R , Estlander T , Henriks-Eckerman M-L , Kanerva L , Stjernvall T
Published: February 2009

A questionnaire survey was carried out among electron microscopy (EM) laboratory technicians in Finland. The questionnaire was returned by 18 out of the total of 45 to 50 EM workers, covering 13 laboratories. Epoxy resins, especially glycidyl ethers of glycerol, anhydride hardeners, amine accelerators, and propylene oxide, where used for embedding. On average, the technicians had been exposed to unpolymerized epoxy resins for 3 h a week over a 10-year period. Ten workers reported skin symptoms. Seventeen used protective gloves when working with unpolymerized resins.

In gas chromatography, the epoxy resins were found to contain many skin sensitizing compounds, that is, diglycidyl ether of bisphenol A (molecular weight 340) and epoxy reactive diluents. This potential allergenic capacity of the epoxy resins emphasizes the importance of preventing skin contact.

Selection of glove material for the handling of tissue specimens in electron microscopy laboratories was based on the results of permeation tests with propylene oxide, because the chemical construction of propylene oxide is similar to that of sensitizing epoxy compounds. Because it is a low viscosity compound, however, propylene oxide penetrates glove material more rapidly than the resin compounds.

Thin polyethylene gloves provide better protection against propylene oxide, and thus also against embedding resins, than disposable polyvinyl chloride (PVC) or natural rubber gloves.
Use of a Relational Data Base for Protective Clothing Research
Authors: Bentz AP , Billing CB , Hendrick MS
Published: February 2009

This paper describes the use of a relational data base for the selection of priority hazardous chemicals to give a reasonable starting point and a logical sequence for conducting development programs involving chemical pollutants. Chemicals considered were those most likely to be encountered in or near a marine environment. The strategy was to gather available information on spill incidence, hazard factors, and need for clothing protection associated with each chemical. The information was stored in a computer with commercially available data base management software. Selection criteria were established for toxicity hazard, spill history, and requirement for an encapsulated suit. Chemicals for testing were sorted using these criteria.
Simulation of the Effect of Moisture Content in Underwear and on the Skin Surface on Steam Burns of Fire Fighters
Authors: Mäkinen H , Smolander J , Vuorinen H
Published: February 2009

About 9% of the injuries to fire fighters in Finland are burns. The majority of the burns on the shoulders and upper arms were caused by a high condensation rate of steam on the skin. The moisture transport from the skin of the subjects to the outer layers of clothing, as well as the heat transfer through the same dry and wet garment layers were measured by fabric tests. The differences between types of underwear, that is, cotton knit, aramid knit, and wool knit fabrics, were sought by the simulation method. Humidity measurements were performed with Vaisala Humicap sensors. The sensor mechanic and computer control systems of the sensor were developed at the Institute of Occupational Health.

Four male firemen served as subjects at 30°C ambient temperature and at 30% humidity. Each exposure lasted for 70 min (20-min rest, 25-min walk, and 25-min rest). The humidity between the skin and the underwear of the back and on the shoulders and between two-garment layers were recorded. The skin temperature was recorded at nine sites. Core temperature, heart rate, and oxygen consumption were also measured. The same layers of clothing were moistened with different amounts of water, and their thermal behavior was evaluated by exposing the garments to a source of radiant heat, 20 kW/m2, according to the second draft of ISO 6942. The lowest moisture content between skin and underwear on the shoulders was measured when woolen underwear was worn, and the highest content when cotton underwear was worn. The moisture content of the garments was lowest in the aramid underwear. The differences were not significant, however, the moisture in clothing decreased the transmission factor, TF20, the time-to-pain, and second-degree burn time. The decrease was drastic when the moisture content rose from 20% to 30 to 40% in underwear.
Analysis of Standards and Testing for Firemen's Protective Clothing
Authors: Abraham CJ , Newman M , Bidanset JH
Published: February 2009

A study was made of standards published since 1970 for firemen's protective clothing. In addition, the state of the art in material science from the early 1960's through 1986, relating to protective clothing, was examined, including testing techniques and development of fire-resistant materials. Studies were performed in conjunction with the remains of protective clothing and equipment exposed to a flashover during residence fire.

The authors conclude that the standards set forth by the National Fire Protection Association, the American National Standards Institute, the American Society for Testing and Materials, and the Occupational Safety and Health Administration do not correlate with the foreseeable exposure temperatures in a burning structure. The materials currently used by fire fighters cannot withstand the extreme heat conditions generated by a flashover. Based upon the findings of the authors, it is necessary to continue to upgrade the preexisting minimum standards to incorporate the state of the art available for protective clothing and equipment.

Upgrading existing standards to reflect the level of available technology would lead to significant improvements in the design and construction of protective gear. In turn, this would result in greater safety for firemen caught in catastrophic fires by reducing foreseeable thermal exposure injury.
Fire Fighter Turnout Clothing: Physiological and Subjective Evaluation
Authors: Huck J , McCullough EA
Published: February 2009

This study collected physical, physiological, and subjective data for different turnout clothing and equipment systems commonly used by fire fighters in the United States. A 3 by 2 by 2 randomized block design was used to determine the effect of (1) garment design; (2) type of moisture barrier; and (3) use or nonuse of a self-contained breathing apparatus (SCBA) on the (1) resistance to dry and evaporative heat transfer provided by the clothing systems measured with a heated manikin, (2) the physiological responses of subjects (that is, rectal temperature, heat rate, weight loss, added energy expenditure, and unevaporated sweat) while performing exercise and wearing the clothing systems, and (3) the subjective responses of subjects after exercise (that is, thermal sensation and wearer acceptability of the clothing systems). Results indicated that the best type of clothing system for structural fire fighting would be either the traditional long turnout coat or the tailed coat worn over waist length pants, constructed with a polytetrafluoroethylene (PTFE) moisture barrier, and worn without a SCBA.
The Role of the U.S. Coast Guard Strike Team in Hazardous Chemical Responses
Authors: Gaines RB
Published: February 2009

This paper discusses the U.S. Coast Guard Atlantic Strike Team, covering the general organization, capabilities, and inventory of response equipment and instrumentation. Because the Atlantic Strike Team has become increasingly involved in federal hazardous waste site activities, the paper focuses on chemical response. In the course of such a response, team members must continually evaluate site hazards and thereby play an active role in the determination of adequate personnel protection equipment. The paper discusses procedures used at the Atlantic Strike Team for making these determinations, as well as identifying those resources available to assist in both level of protection and protective suit material selection decision logic.
An Improved Air-Supplied Plastic Suit for Protection Against Tritium
Authors: Wiernicki C
Published: February 2009

A new two-piece, air-supplied, plastic suit has been developed for use in atmospheres containing tritium oxide (HTO). The suit material is 9 mils thick and consists of two 4-mil pieces sandwiched around a polyester scrim for added strength. Each of the 4-mil sections is a laminate of vinylidene chloride (Saran), chlorinated polyethylene (CPE), and ethylene vinyl acetate. The Saran/CPE suit material and 12-mil polyvinyl chloride (PVC), the suit materials previously used in HTO atmospheres, were tested for tritium permeation by the Radian Company. Tritium permeation testing was done in accordance with the ASTM Test Method for Resistance of Protective Clothing Materials to Permeation by Liquids or Gases (F 739-85) using the Radian Microcell. Liquid scintillation counting techniques were used to measure the amount of HTO collected. The two plastic suit materials were challenged with the following: HTO/Duo Seal, 1 mCi/mL. Tritiated water (10 mCi/mL) permeated both materials; however, permeation was at least four times slower, and breakthrough six times longer, for Saran/CPE. HTO in Duo Seal penetrated the 12-mil PVC in 100 min, but did not penetrate the Saran/CPE during the entire 480-min test. No breakthrough was detected with either material when challenged with HTO (1 mCi/mL) in Freon TF or ethanol. The Saran/CPE suit material provides significantly better protection against tritium oxide than 12-mil PVC. In addition, the Saran/CPE plastic suit has an internal noise level of 73 dba, is self-extinguishing, and provides a protection factor of greater than 20 000 when tested against a polydispersed aerosol.
Evaluation of the Physiological Parameters Associated with the Propellant Handler's Ensemble
Authors: Doerr DF
Published: February 2009

Work involved during the preflight preparation of spacecraft involves the handling of materials that are very toxic to humans. These toxins attack the respiratory and skin systems and, therefore, impose the requirement for full suit enclosures. The weight, structure, and operating parameters of such a suit can be expected to have a significant effect upon the metabolic and thermal responses of the user, especially in high workload situations and ambient temperature extremes.

This paper describes the testing of the operational version of the Propellant Handler's Ensemble (PHE). In particular, parameters affecting the physiology of the user were measured during a work-rest regimen performed in three temperature environments: −7, 23, and 43°C (20, 74, and 110°F). Six subjects performed tests in these environments in two versions of the PHE, the autonomous backpack version and the hoseline supplied configuration. Measurements included heart rate, four skin temperatures, rectal temperature, oxygen and carbon dioxide in the helmet area, suit pressure, and interior suit temperature.

It was concluded that the weight and configuration of the suit significantly influenced the physiological stress on the user. The weight, at 29.5 kg (65 lb) for the PHE and backpack, proved to be a primary stressor, as indicated by elevated heart rates. The high workload portion of the protocol also taxed the limit of the environmental control unit because of the increased respiratory requirements. Oxygen levels dropped as much as 4% below resting levels and the carbon dioxide level increased by a similar amount. Finally, thermal stress is clearly evident, especially in the 43°C (110°F) tests.

State-of-the-art design techniques in whole body suits do not provide solutions to these problems. Therefore, it has been necessary to institute operational restrictions and impose medical and physical standards to avoid situations that could adversely affect the well-being of the worker.
Protective Clothing for Crop Consultants: Field Studies in Louisiana
Authors: Cloud RM , Boethel DJ , Buco SM
Published: February 2009

Factors affecting the level of foliar residue transfer of permethrin to the clothing of crop consultants working in aerially sprayed soybean fields were studied. Significant variation occurred by subject in the degree of exposure of specimens taken from specific locations on garments. Results indicated that ultra-low-volume oil spray techniques increase the level of residue transfer to clothing. Delayed entry is highly effective in reducing the degree of clothing contamination. Fiber content of fabrics worn into fields had some effect, but presence or absence of applied surface finishes had little or no effect.
Mechanisms of Clothing Exposure and Dermal Dosing during Spray Application
Authors: Popendorf W
Published: February 2009

This report focuses on the mechanisms underlying the various sources of exposure during two replicate exposure studies of two ground crews applying Difolatan 80 Sprills (80% captafol) in central Florida orange groves.

Aerosolized captafol concentrations averaged 56 µg/m3 for mixer-loaders and 34 µg/m3 for spray applicators but were not statistically different.

Dermal “exposures” (outside the coveralls) were consistent within participants but not within operations for reasons that are compatible with observed differences in work conditions. The density of exposure ranged roughly from 1 to 10 µg/h/cm2 to the hands, legs, and arms (but up through 20 when direct contact with captafol solutions was evident) to 0.1 to 1 µg/h/cm2 for other locations. Whole-body exposures had a mean of 40 mg/h and ranged from 15 to 116 mg/h, with the hands accounting for around 40% of these totals.

Dermal “doses” (inside the coveralls) were reduced and generally more uniform than either dermal exposures or aerosols. Penetration through the cotton-polyester coveralls differed from a mean of 2% for the spray applicators to 7% for the mixer-loaders, for reasons believed to be related to wet versus dry deposition, respectively. This protection reduced skin dosing densities under the coveralls to 0.01 to 0.1 µg/h/cm2 except to the largely horizontal upper legs and lower arms that ranged from 0.1 to 0.5 µg/h/cm2. Whole-body doses had a mean of 19 mg/h and ranged from 10 to 30 mg/h, with hands accounting for around 90% of these totals. Laboratory methods to predict the clothing penetration rates in similar field settings are needed.
Development and Validation of a Laboratory Spray System Designed to Contaminate Fabrics with Pesticide Solutions
Authors: Leonas KK , DeJonge JO , Duckett KE
Published: February 2009

A chamber designed to contaminate fabric samples by delivering controlled amounts of pesticide solution has been constructed. The pesticide solution is applied in spray from simulating droplets as found in actual field pesticide spraying of crops. This chamber provides a systematic method for evaluating barrier properties of fabrics under consideration for use in protective clothing for agricultural workers. The design and operation procedures are discussed in terms of its applicability as a standard test method for pesticide penetration of textiles and protective fabrics.
Dispersion Mechanism of a Pesticide Chemical in Woven Fabric Structures
Authors: Kim CJ , Kim J-O
Published: February 2009

The dispersion mechanism of a DDT solution in a variety of woven fabric structures is described. The dispersion is illustrated by scanning electron microscope (SEM) micrographs and related to fiber morphology, fabric geometry, weight, and finish. The kinetics of dispersion is related to the size and shape of the dispersion area and to the concentration of radioactive-labeled DDT. Findings show that final location of DDT within textile substrates is related to fiber content and morphology, fabric geometry, and finish. Fiber irregularities serve as deposit sinks for the chemical soil. The finish influences soil dispersion by making the fiber surface smoother. Fabric weight and geometry determine the size and shape of the dispersion area. The maximum concentration of DDT deposit is found to be at the outermost boundary of the dispersion area, not at the center.
Chlorpyrifos Residue Removal from Protective Apparel Through Solvent-Based Refurbishment Procedures
Authors: Ringenberg KP , Laughlin JM , Gold RE
Published: February 2009

Dry-cleaning solvent (tetrachloroethylene) and the dry-cleaning procedures were studied in the refurbishment of chlorpyrifos-contaminated clothing. Also evaluated were solvent-based pretreatments followed by laundering. Fabrics were a 100% cotton and a 50% cotton/50% polyester each either with a renewable, soil-repellent finish, or unfinished. Field strength chlorpyrifos (0.5% active ingredient), prepared from emulsifiable concentrate formulation, was pipetted onto specimens which were then dry-cleaned or laundered following solvent pretreatment. Transfer of pesticide from contaminated to uncontaminated fabric specimens was also studied.

Dry-cleaning treatments were most effective, with less than 1% chlorpyrifos residue remaining on fabric specimens. Mechanical agitation was an aid in chemical removal. Pesticide transfer to the uncontaminated fabrics was minimal, but did occur. Pretreatments, followed by laundering, were less effective than dry-cleaning procedures.
Effect of Formulation on Removal of Carbaryl and Chlorothalonil from Apparel Fabrics by Dry Cleaning, Aqueous Extraction, and Vaporization
Authors: Fleeker JR , Nelson C , Wazir MF , Olsen MM
Published: February 2009

Several methods were examined for efficacy in removal of carbaryl and chlorothalonil contamination from indigo-dyed cotton twill, undyed cotton twill, polyester/cotton broadcloth, and cotton weft knit terry. Fabrics were contaminated with commercial formulations of carbon-14 labeled carbaryl and chlorothalonil, as well as pure carbaryl and chlorothalonil. Vaporization of the pesticides over a 21-day period resulted in a loss of up to 35% of the carbon-14. A hydrocarbon-based dry cleaning solvent was ineffective in removing the pesticides, while a perchloroethylene-based solvent removed ≥76% of the pesticides. More of the pure form of the pesticides was extracted than the formulated form. Repeated extraction with warm water removed 80 to 98% of the pesticides except for pure chlorothalonil of which 40 to 60% was removed. The inert ingredients in the commercial formulation of chlorothalonil appear to increase the efficiency of aqueous extraction.
Use of Methylene Blue Dye to Predict Fabric Penetration by Malathion
Authors: Hobbs NE , Oakland BG
Published: February 2009

This study developed and verified a test method for the screening and selection of fabric finishes proposed for use in protective garments for agricultural workers exposed to pesticide sprays. Six nonwoven and four woven fabrics with and without barrier finishes were tested for aerosol spray penetration using 0.1% methylene blue dye as an indicator of pesticide penetration with three spray emulsions: (1) water; (2) water/surfactant (48:1); and (3) unrefined cottonseed oil/surfactant (4:1). The procedure was repeated using the following pesticide emulsions: (1) water/malathion (100:4) and (2) unrefined cottonseed oil/malathion (100:8).

Analysis of variance was used to compare the results of the water/malathion and the results of the cottonseed oil/malathion spray tests between categories of dye penetration. In each case, there was significant difference between group variation. Duncan's Multiple Range Test (p < 0.05) indicated that fabrics that did not allow penetration by the methylene blue dye had significantly lower levels of malathion present in the extracts. The spray tests indicated that aerosol spray penetration was reduced by the presence of fluorocarbon barrier finishes on the fabrics.
Impact of Labor Protection in the Registration Process of Pesticides in the Netherlands
Authors: Maas CL
Published: February 2009

Pesticide registration in the Netherlands is the responsibility of four governmental departments dealing with (1) agriculture, (2) public health, (3) environment, and (4) occupational health and safety. It is the responsibility of the Directorate-General of Labour (DGA) within the Ministry of Social Affairs and Employment to direct the evaluation of occupational toxicity and exposure data. Further, DGA maintains via the Labour Inspectorate standards of application technology; procedures for storage, mixing and loading; sound hazard communication; and the quality of protective measures. The ultimate goal is to achieve a quality of health and safety in agriculture comparable to other work places where toxic materials are used. Therefore, consistency with premanufacturing notification policy, for example, is obligatory.

As far as labor protection is concerned, the registration process of pesticides starts with toxicology. The relevant adverse effects determined in experimental animals are further evaluated if dose levels at which these effects occur indicate serious risk during or after occupational exposure via the dermal, inhalation, or secondary oral route. Quantitative exposure assessment is then carried out. Currently, a systematic approach for gaining exposure data is being developed in the Netherlands. This process is a multistep system consisting of (1) theoretical estimation of exposure, (2) using mathematical models and generic data, (3) personal dermal monitoring, (4) environmental (air) monitoring and personal air monitoring, and (5) biomonitoring.

Higher levels in the system are triggered if results at lower levels seem to have serious implications. In certain situations, a combination of elements from different levels within one study may have advantages. The exposure data then are challenged by an extrapolated human threshold dosage-level in order to rationally decide on registration. This approach of weighing possible risks is carried out for all relevant differential applications. Special attention is paid to indoor applications, like thermically isolated warehouses.

When the decision to register a pesticide has been made, different instruments may be used to control the actual exposure by defining the application technology and using warnings on the label, ergonomic packaging, and protective clothing. The Labour Inspectorate may add special protective measures to these demands for separate locations. During the registration, DGA may ask for further testing either in toxicology or exposure issues. The field data reported by the Labour Inspectorate provide feed-back on registration decisions. Efforts to answer questions concerning pesticide application and regulation are preferentially to be improved by a joint effort of the pesticide industry, the farmers, their organizations, and the registration authorities, all cooperating for better labor protection.
Pesticide Information and Attitudes Toward Chemical Protective Clothing Among Urban Pesticide Users
Authors: Rucker M , Grieshop J , Peters A , Hansen H , Frankie G
Published: February 2009

The objective of this project was to obtain data on the attitudes and practices of urban users of pesticides, especially as they related to protective clothing and use of pesticide labels for information on safety precautions. Results of a mail survey indicated that over one-fourth of the sample experienced health problems associated with pesticides and about 5% were serious enough to require professional help. The survey and followup interviews suggested that ‘many consumers are disinclined to use any protective gear for home use of pesticides or give special care to clothing worn when applying pesticides. Reasons for these attitudes included perceived protection by government, little danger in low dosages, and the expenses and possible social ridicule involved in use of special gear. Problems in using pesticide lables for safety information included the high volume of badly organized information, technical jargon including the signal words, and spillage obliterating the instructions.
A Review of the Requirements for Protective Clothing for Agricultural Workers in Hot Climates
Authors: Litchfield MH
Published: February 2009

The wearing of additional protective clothing has to be viewed in the overall context of recommendations for the safe and effective use of pesticides. In hot climates, the wearing of such protective clothing is more problematical than in temperate climates because of the heat and stress factors involved. Materials that make up protective clothing need to be comfortable to the wearer in a hot climate and also be protective to a variety of pesticide formulations. These materials should also be available at low cost for use in developing countries. The range of potentially acceptable materials, their availability, wearer acceptability, and performance in the field is reviewed in this paper.

Protective clothing should be designed according to the requirements of the situation, for example, for workers handling concentrated formulations or when spraying diluted solutions. More research into the problems in hot climates is needed, and the direction of this effort is discussed at the conclusion of this paper.
Protective Clothing and Equipment: Beliefs and Behavior of Pesticide Users in Ecuador
Authors: Grieshop JI
Published: February 2009

Although protective clothing and equipment are designed to provide protection to pesticide users, they are often not used by small farmers in developing countries such as Ecuador, South America. Protection is not used because of its high cost, inappropriateness, and the lack of availability to users who could be at great personal risk when using pesticides. Other important obstacles to their use are inaccurate “folk beliefs” about pesticides and pest management. These beliefs, although consistent with the Ecuadorean farmers' and nonfarmers' views that pesticide materials are not hazardous and that only weak individuals are at risk, are at odds with what is known about pesticides and the potential risks from misuse. Greater efforts must be made to understand pesticide users' beliefs and behaviors if pesticide safety education programs are to be effective and if users are going to be educated to use protective clothing and equipment.
Conductive Clothing and Materials
Authors: Davies J
Published: February 2009

In the last few decades, many challenges have had to be met in protecting the human in industry against a large variety of hazards. In a number of areas in the world, maintenance work is required to be carried out on and in the vicinity of very high-voltage electrical equipment and in particular on overhead transmission lines while they are still energized.

To protect workers under these and similar situations, suits made from conducting materials are required. The early suits were considered very inefficient due to their inferior design and construction and poor electrical properties.

The practical functions of a Conductive Clothing Assembly extend far wider than the provision of adequate conductivity, flame retardancy, wear resistance, electrical resistance, current carrying capability, screening efficiency, ease of cleaning and maintenance, together with wearer acceptance and comfort, all have to be met.

This paper describes the initial investigations and development of conductive composite textile materials for a protective clothing assembly to combat the pick up from the electrostatic field in the immediate vicinity of 400-kV substation equipment and overhead line transmission towers giving a work environment where inductance buildup of electrical energy could occur to workers and subsequent earthing could result in a discharge above the threshold of feeling.

A review of the requirements of the new International Electrotechnical Commission Standard 78-15 Specification for Conductive Clothing for Live Working is also included in the paper together with a survey of the current work being undertaken in furthering the development of conductive composite materials.
Kinetics of Vapor Sorption by Latex-Bonded Carbon Particles
Authors: Jones DW , Watts P
Published: February 2009

A study has been made of the sorption of isopropyl methylphosphonofluoridate vapor (IMPF) by an air-permeable protective material consisting of powdered activated carbon bonded to a fabric substrate. The interactions of IMPF with individual components of the system have been studied prior to examination of the composite material. The solubility and diffusivity coefficients of IMPF in films formed from two different acrylic latex binders have been determined by gravimetric sorption methods. Sorption of IMPF vapor by the activated carbon and the fabric substrate has been measured gravimetrically. Experimental materials employing different binders and carbon loadings have been prepared, and the uptake of IMPF vapor determined.

Vapor sorption by these materials has been studied under dynamic conditions of flow through the material, and breakthrough profiles have been obtained. A mathematical model of dynamic vapor sorption has been developed that accurately reproduces the experimentally observed results. This model divides the adsorbent into regions of different prevailing sorption kinetics. The major region has a sorption rate that is determined solely by mass transport of vapor. The remaining “slow” region shows sorption kinetics that are consistent with a slow surface deposition or displacement reaction as the rate determining step. Even though all of the carbon particles are coated with a film of binder, permeation through this film is not rate-controlling step. The “dynamic” sorption capacity of carbon incorporated into the material is largely uninfluenced by the presence of the latex binder.

The mathematical model is successful in predicting the performance of multiple-layer assemblies from the results observed on single layers, and this provides a verification of the approach to the analysis of the sorption kinetics. The model is useful in providing guidelines to show how the material performance may be improved, and indicating the research avenues that are most likely to lead to useful developments.
Evaluating a New Material for Use in Totally Encapsulating Chemical Protective Suits
Authors: Stull JO , Jamke RA , Steckel MG
Published: February 2009

A totally encapsulating suit has been developed by the U.S. Coast Guard to provide a high level of protection for response personnel during chemical spills. The suit is fabricated by Chemical Fabrics Corporation (CHEMFAB) using a new material, Challenge 5100. Challenge 5100 is CHEMFAB's aramid-reinforced fluoroelastoplastic composite that has demonstrated excellent chemical resistance against a variety of chemical solvents. Other components of the suit include a Teflon FEP visor, Teflon TFE film gloves, a pressure sealing zipper, and various liquid-proof seam constructions. The Coast Guard and Chemical Fabrics Corporation are extensively testing these materials and components against selected chemicals to determine suit capabilities and limitations. The results of the testing program will be used to make suit use recommendations, as well as support further optimization of suit materials and construction.
ESD Packaging and Handling Problems—the Government Perspective of Causes and Cures
Authors: McGill R
Published: February 2009

The packaging of items has seen a growing dependency on various forms of plastic products. This trend away from the simple wood and paper materials in earlier use has occurred during a time when microcircuit technology was giving the consumer smaller more portable electronic components. However, the increased susceptibility of these items to damage caused by electrostatic discharge (ESD) as their size decreases, is in stark contrast to the inherent vulnerability of plastic packaging materials to create static charges. The government, because of its complex distribution network, has a direct interest in solving these ESD protective packaging problems.

Through a series of key initiatives, the government has focused the attention of various industry associations that represent both ESD sensitive item and ESD protective packaging material suppliers to the needs of the military logistical environment. In so doing, the crucial development of reliable test standards, establishment of ESD protective control techniques, and the standardization of ESD sensitive item identification, marking and common handling procedures offer the promise of benefiting industry as much as the Government itself. A true cure for packaging and handling problems in Government will be dependent upon close coordination and communication among all elements to include production engineering and research and development oriented activities. Specific problems and their impact on day-to-day government operations are discussed as well as steps being taken to correct recognized deficiencies.