bluuebunny/crossref_metadata_2025 huggingface dataset:
Refinements to Pressure Vessel Steel Embrittlement Correlations
Authors: Byrne ST , Hardies RO
Published: March 2009

ASTM E 900-87, Standard Guide for Predicting Neutron Radiation Damage to Reactor Vessel Materials, provides methods for predicting the effects of fast neutron irradiation on the toughness of reactor pressure vessel materials. The prediction methodology is similar but separate for the steel base metal and weld metal. The methodology relies on a correlation between the chemical content of the steel and the fast neutron fluence. The prediction methodology is used to assess the margin of safety against fracture of the reactor vessel during normal operation and postulated transients.

The purpose of this paper is to describe the results of an effort to improve the accuracy of the predictions of transition temperature shift. Numerous issues have been identified which could influence the calculational approach. Those issues include: • the quality of the input data • the dependence on irradiation temperature • differences in irradiation response between unique subsets (e.g., between welds deposited by different fabrication process and consumables) • saturation of neutron damage at “end-of-life” neutron fluences • saturation of neutron damage above copper solid solubility limits (i.e., modification of the “chemistry factor” above 0.25 to 0.30 weight percent copper) • the significance of minor variations in copper or nickel content within the base metal or weld to the relative sensitivity to neutron damage

This evaluation was performed using a “scrubbed” data base of reactor vessel surveillance data coupled with best-estimate irradiation temperatures; the latter were based on the reactor vessel cold leg temperatures rather than the “go” / “no go” thermal monitor data. A term for dependence on irradiation temperature was derived and added to the correlation for irradiation induced shift of the transition temperature. The assumption used was that differences in irradiation temperature were a significant contributor to the scatter, or standard deviation. Once that scatter was reduced, the other more subtle factors identified above could be quantified. Factors considered in this evaluation were weld fabrication process and saturation at copper solubility limits.

The ultimate objective is to contribute to the development of an improved understanding of the empirical relationships which, when coupled with theoretical models of irradiation damage mechanisms, will result in more accurate correlations for inclusion in ASTM E 900. The data base improvements, addition of a temperature term, consideration of saturation effects (with neutron fluence or copper content) and separation by material subsets are intended to assure that the best estimate predictions and their uncertainty are as realistic as possible.
Development of Embrittlement Prediction Models for U.S. Power Reactors and The Impact of The Heat-Affected Zone to Thermal Annealing
Authors: Wang JA
Published: March 2009

The NRC Regulatory Guide 1.99 (R.G. 1.99) Revision 2 was based on 177 surveillance data points and the EPRI data base, where 76% of 177 data points and 60% of EPRI data base were from Westinghouse's data. Therefore, other vendors' radiation environment may not be properly characterized by R.G. 1.99's prediction. To minimize scatter from the influences of the irradiation temperature, neutron energy spectrum, displacement rate, and plant operation procedures on embrittlement models, improved embrittlement models based on group data that have similar radiation environments and reactor design and operation criteria are examined. A total of 653 shift data points from the current PR-EDB, including 397 Westinghouse data, 93 B&W data, 57 CE data, and 106 GE data, are used. A nonlinear-least-squares fitting FORTRAN program, incorporating a Monte Carlo procedure with 35% and 10% uncertainty assigned to the fluence and shift data, respectively, was written for this study. In order to have the same adjusted fluence value for the weld and plate material in the same capsule, the Monte Carlo least-squares fitting procedure has the ability to adjust the fluence values while running the weld and plate formula simultaneously. Six chemical components, namely, copper, nickel, phosphorous, sulfur, manganese, and molybdenum, were considered in the development of the new embrittlement models. The overall percentage of reduction of the 2-sigma margins per ▵RTNDT predicted by the new embrittlement models, compared to that of R.G. 1.99, for weld and base materials are 42% and 36%, respectively. Currently, the need for thermal annealing is seriously being considered for several A302B-type RPVs. From the macroscopic view point, even if base and weld materials were verified from mechanical tests to be fully recovered, the linking heat-affetcted zone (HAZ) material has not been properly characterized. Thus the final overall recovery will still be unknown. The great data scatter of the HAZ metals may be the result of the metallurgical heterogeneity that exists in the HAZ. The proposed data fitting procedure for the HAZ material is presented in the paper.
Changes in Electromagnetic Properties of a Low-Alloy Steel Caused by Neutron Irradiation
Authors: Goto T , Kamimura T , Kumano S , Takeuchi I , Maeda N , Yamaguchi A
Published: March 2009

In order to develop a method for the nondestructive evaluation of material deterioration in nuclear pressure vessels, changes in the electromagnetic properties of the low-alloy steel A533B, Class. 1 and its weld metal caused by neutron irradiation up to ∼3x1023 n/m2 of neutron fluence at 561K were measured. Electrical resistance, coercivity and Barkhausen noise were selected as the electromagnetic properties to measure. It was found that decreases of several % in the readings of electrical resistance and coercivity, and an increase of several % in the Barkhausen noise occurred due to neutron irradiation. Good correlations between the changes in the electromagnetic properties and those in the mechanical properties were confirmed. Furthermore, an equation using the results of the three tests was found to estimate well the transition temperature and yield strength. From this, the authors conclude that the electromagnetic tests have potential as methods for nondestructive evaluation of material deterioration in the reactor vessels of nuclear power plants.
The Modelling of Combined Radiation-Induced and Thermal Non-Equilibrium Segregation of Chromium in Neutron-Irradiated Austenitic Stainless Steels
Authors: Goodwin CC , Faulkner RG , Fisher SB
Published: March 2009

A model of the radiation-induced segregation (RIS) and thermal non- equilibrium segregation (TNES) at grain boundaries has been established within a phenomenological theory. This model indicates that the magnitude and extent of segregation is dependent upon the formation of solute-point defect complexes that migrate to grain boundaries. Theoretical predictions are made for the TNES and RIS of chromium in austenitic stainless steels for the first time. The results indicate that for TNES, chromium creates a positive binding energy in the complex, and is thus enriched at the grain boundary. For RIS, chromium produces a negative binding energy in the complex, and is thus depleted at the grain boundary. The combined effect of the two segregation mechanisms is discussed in relation to the evolution of the segregation profile exhibited by the grain boundary. The segregation profiles are shown to be illustrative of analytically measured profiles for similarly treated materials.
Radiation-Induced Instability of MnS Precipitates and its Possible Consequences on Irradiation-Induced Stress Corrosion Cracking of Austenitic Stainless Steels
Authors: Chung HM , Sanecki JE , Garner FA
Published: March 2009

Irradiation-assisted stress corrosion cracking (IASCC) is a significant materials issue for the light water reactor (LWR) industry and may also pose a problem for fusion power reactors that will use water as coolant. A new metallurgical process is proposed that involves the radiation-induced release into solution of minor impurity elements not usually thought to participate in IASCC. MnS-type precipitates, which contain most of the sulfur in stainless steels, are thought to be unstable under irradiation. First, Mn transmutes strongly to Fe in thermalized neutron spectra. Second, cascade-induced disordering and the inverse Kirkendall effect operating at the incoherent interfaces of MnS precipitates are thought to act as a pump to export Mn from the precipitate into the alloy matrix. Both of these processes will most likely allow S, which is known to exert a deleterious influence on intergranular cracking, to re-enter the matrix. To test this hypothesis, compositions of MnS-type precipitates contained in several unirradiated and irradiated heats of Type 304, 316, and 348 stainless steels (SSs) were analyzed by Auger electron spectroscopy. Evidence is presented that shows a progressive compositional modification of MnS precipitates as exposure to neutrons increases in boiling water reactors (BWRs). As the fluence increases, the Mn level in MnS decreases, whereas Fe level increases. MnS precipitates were also found to be a reservoir of F, an impurity implicated with cracking of F-contaminated shielded-metal- or submerged-arc welds such as BWR core shroud weld.
Temperature Dependence of the Deformation Behavior of Type 316 Stainless Steel after Low Temperature Neutron Irradiation
Authors: Robertson JP , Ioka I , Rowcliffe AF , Grossbeck ML , Jitsukawa S
Published: March 2009

The effects of low temperature neutron irradiation on the tensile behavior of type 316 stainless steel were investigated. A single heat of solution annealed type 316 stainless steel was irradiated to 7 and 18 dpa at 60, 200, 330, and 400°C. The tensile properties as a function of dose and as a function of temperature were examined. Large changes in yield strength, deformation mode, strain to necking, and strain hardening capacity were seen in this irradiation experiment. The magnitudes of the changes are dependent on both irradiation temperature and neutron dose. Irradiation can more than triple the yield strength over the unirradiated value and decrease the strain to necking (STN) to less than 0.5% under certain conditions. A maximum increase in yield strength and a minimum in the STN occur after irradiation at 330°C but the failure mode remains ductile.
Microstructural and Microchemical Characterisation of Ferritic Ex-Service Magnox Control Rod Sheath Material
Authors: Walmsley J , Fisher S , Spellward P
Published: March 2009

Microstructural characterisation has proven an essential part of a Post Irradiation examination (PIE) programme for ex-service Magnox Reactor Safety Control Rods material. Clad ductility of the component is a key parameter and this can be assessed microstructurally by Transmission Electron Microscope examination. After service, one specific control rod was found to have suffered damage to its outer ferritic steel sheath. Using an understanding of the mechanisms for copper precipitation and dislocation loop formation under reactor operating conditions, it was possible to make an estimate of the operating temperature of the component. This was calculated to be 285±15°C, considerably lower than the nominal operating temperature of ∼350°C. In support of this measurement, direct comparison with work on dislocation loop formation in ferrovac iron, irradiated to a comparable neutron dose over a range of temperatures, suggests an irradiation temperature of ∼280°C, derived from the comparison of mean dislocation loop size.
Tensile and Charpy Impact Properties of Irradiated Reduced Activation Ferritic Steels
Authors: Klueh RL , Alexander DJ
Published: March 2009

Tensile tests were conducted on eight reduced-activation Cr-W steels after irradiation to 15–17 and 26–29 dpa, and Charpy impact tests were conducted on the steels irradiated to 26–29 dpa. Irradiation was in the Fast Flux Test Facility at 365 °C on steels containing 2.25–12% Cr, varying amounts of W, V, and Ta, and 0.1%C. Previously, tensile specimens were irradiated to 6–8 dpa and Charpy specimens to 6–8, 15–17, and 20–24 dpa. Tensile and Charpy specimens were also thermally aged to 20000 h at 365°C. Thermal aging had little effect on the tensile behavior or the ductile-brittle transition temperature (DBTT), but several steels showed a slight increase in the upper-shelf energy (USE). After ≈7 dpa, the strength of the steels increased and then remained relatively unchanged through 26–29 dpa (i.e., the strength saturated with fluence). Post-irradiation Charpy impact tests after 26–29 dpa showed that the loss of impact toughness, as measured by an increase in DBTT and a decrease in the USE, remained relatively unchanged from the values after 20–24 dpa, which had been relatively unchanged from the earlier irradiations. As before, the two 9Cr steels were the most irradiation resistant.
Void Swelling of Copper and Copper Alloys Induced by Heavy Ion Irradiation
Authors: Muroga T , Matue T , Watanabe H , Yoshida N
Published: March 2009

Microstructures of Cu, Cu-5Ni and Cu-3.5Zn irradiated with heavy ions at 523 K to 773 K to a dose of 15 dpa were examined. The addition of nickel or zinc was shown to result in an upward shift of the peak void swelling temperature. Although the results are consistent with those of a previous fast neutron irradiation experiment taking difference in the damage rate into account, the microstructural processes seem not to be a simple shift of temperature.
The Neutron Irradiation Effect on the Mechanical Properties and Structure of Beryllium
Authors: Fabritsiev SA , Pokrovsky AS , Bagautdinov RM
Published: March 2009

The results of an investigation into the effects of neutron irradiation on the mechanical properties and structure of beryllium are presented. Irradiation was performed in the BOR-60 reactor up to doses of 0.7–1.1 × 1022 n/cm2 (E > 0.1 MeV) at irradiation temperatures of 350°C, 400°C, 520°C, 780°C. Two modifications of RF beryllium, i.e. DShG-200 and TShG-56, were chosen for investigation.

For irradiation at temperatures of 350 – 400°C Be hardening due to the accumulation of radiation defect complexes. Hardening is accompanied with a sharp drop in plasticity at Ttest ≤ 300°C. The fracture of samples is of brittle, mainly transcrystallite, type. High-temperature irradiation (Tirr = 780°C) gives rise to large helium pores over the grain boundaries and smaller pores in the grain body. Fracture is brittle and intercrystalline at Ttest ≥ 600°C. Helium embrittlement is also accompanied with a drop in the Be mechanical properties. The conclusion is made that the irradiation temperature range, where irradiated beryllium has a satisfactory level of properties, is rather narrow: 300°C ≤ T ≤500°C.
A New Test Method to Evaluate the Cut Resistance of Glove Materials
Authors: Lara J , Turcot D , Daigle R , Boutin J
Published: March 2009

A new method to evaluate the cut resistance of protective glove materials has been developed. The method consists of sliding a straight blade on a sample material and determining the horizontal blade displacement required to cut the material at a given load. A special arrangement allows a load applied on the sample material to be kept constant throughout the test. The effect on the cutting results of a) degradation in blade sharpness, b) blade speed, c) sample holder geometry (semi-circular or flat), and d) the load applied was characterized. The results demonstrated that a) the blade edge degraded even with soft materials such as neoprene; b) the blade speed had a negligible effect on the cutting results; c) the holder's geometry does not have a significant effect on the variability in the cutting results, but the use of a semi-circular holder is recommended; and d) the applied load is a function of the material's cut-resistance. It was found that the blade displacement increases non-linearly with the applied load. The cutting test conditions were set as follows: the blade is 70 mm long and its speed is 150 mm/min; the blade edge must be used only once. To evaluate the resistance of a material to cutting, tests must be performed with at least two different loads. The load required to cut a material to a standardized distance, namely 10 mm, is calculated by interpolating the experimental values. However, in the preferred method, the cut test is performed with three or four different loads and the load required to cut to 10 mm is calculated by a non-linear regression. Results are reproducible with a coefficient of variation (CV) lower than 16% with homogeneous materials. However, higher CV's are obtained with knitted materials such as Kevlar gloves, or steel reinforced materials.
Testing of Protective Clothing for Motorcyclists: Validation of Laboratory Tests by Accident Studies.
Authors: Woods RI
Published: March 2009

Four test methods have been developed for testing motorcycling clothing: a belt abrasion test, a pressure burst test, an impact cut test and the belt abrasion test with impact. These have been used on the same pieces of materials as were previously tested on a dummy in a simulated accident. The laboratory test methods allow the protective qualities of the materials to be correctly ranked. This was not true with methods used previously. The test methods can also distinguish between crash-damaged clothing that proved protective in a crash and that which did not. The methods can be used to devise specifications for motorcycling clothing, and to develop novel materials for such clothing.
A New Test Method to Measure Triboelectric Static Charge Generation on Protective Clothing Materials
Authors: Stull JO , Greimel TC
Published: March 2009

Different test methods for evaluating hazards resulting from static charge development and static charge decay on protective clothing materials have been developed. These test methods involve both the application of electrical charge and the measurement of surface resistivity by means of surface electrodes. Misleading information can be produced utilizing the electrode charge decay method when a material has low conductivity. When a material has low conductivity, it is possible that either no charge is developed, or anomalous readings of static charge occur when in actuality no charging or discharging of the material has taken place. In addition, these methods do not employ techniques which simulate the conditions of actual use of a material.

The triboelectric method developed by the National Aeronautics and Space Administration (NASA), can be utilized to circumvent some of the shortcomings of the electrode methods. With the triboelectric method, static charge is developed on the test material by means of rubbing friction, thus simulating the manner of actual use of the protective garment. Reproducible application of static charge can be accomplished by way of a polytetrafluoroethylene (PTFE) felt wheel which is rubbed against the test specimen for ten seconds. The peak voltage and charge decay rate for five seconds after cessation of rubbing are recorded. This paper gives a complete description of the test method, its development, applications, and provides results on a series of sample materials using this technique. Results of the triboelectric test method are also compared against other industry standards.
Evaluation of Health Care Workers' Apparel Using Microbiological Methods
Authors: Placencia AM , Peeler JT
Published: March 2009

Health Care Workers are exposed to numerous biological hazards in the work place. This can occur in hospitals, care centers, laundry facilities, laboratories and other units dealing with the various aspects of health care. Some of these biological hazards can lead to death and the economic and emotional impact can be costly. This burden falls not only on the health care worker and individuals receiving these services but also on industry and government.

There is a need to develop methods appropriate for evaluating protective wear against microbial as well as viral hazards. These hazards not only occur through fluid contamination like blood, serum but also through aerosol transmission.

A method has been developed to evaluate the biobarrier properties of materials using either a bacterial spore or a bacteriophage. The indicator organism was aerosolized in an acrylic chamber. Filtration cups containing the testing material were exposed to the indicator organism consisting of B. subtilis var. niger spores. The materials were ranked by comparing the number of organisms that penetrated the material to the initial number exposed.
A Novel Method for Quantification of Surgical Gown Permeability
Authors: Wick TM , Flaherty AF
Published: March 2009

Transmission of blood-borne pathogens between patients and health care professionals, including the AIDS virus and hepatitis B, is a significant concern of the medical community. Surgical gowns and drapes represent a major barrier for protection against possible transmission of blood and blood-borne pathogens. In order to predict the effectiveness of gown fabrics as transport barriers, we developed a laboratory apparatus to quantify the liquid permeability of five commercially available surgical gown fabrics challenged with blood under conditions mimicking those measured during pressing and leaning motions. This Pressing/Leaning Simulator represents a simple, inexpensive, and reproducible test to quantify the amount of blood transport across a fabric during surgery or other medical procedure. These data will assist gown users in selecting the appropriate gown and gown manufacturers in developing gowns that present an adequate moist transfer barrier for the duration of a gowns intended use.
Humidity Considerations for Protective Fabric Evaluation
Authors: Carr ME , Koals MA , Vandersall MT
Published: March 2009

An important consideration in the evaluation of personal protective equipment is the physical environment which the equipment will encounter during use. For many materials used in protective clothing, the effect of elevated humidity on protective capacity may be negligible. For protective clothing incorporating carbonaceous materials like activated charcoal, which protect by adsorbing hazardous vapors, however, humidity considerations may be extremely important. Various carbonaceous materials have been evaluated for protective capacity with industrially important, hazardous chemicals at elevated relative humidity. Significantly large differences are evidenced in the effect of humidity on adsorptive capacities of these materials. Standard protective fabric evaluation methods have been modified to allow elevation of relative humidity and monitoring of its effect on protective capacity. Protective capacity data for fabrics are similar to those obtained for the neat carbonaceous materials for at least one hazardous, industrial solvent, carbon tetrachloride.
Effects of Biaxial Tensile Strain on Hydrocarbon Permeability of Butyl Rubber Composite Barriers
Authors: Lee BL , Yang TW , Hassler KD , Wilusz E
Published: March 2009

A study has been initiated to assess hydrocarbon permeability of carbon black-reinforced butyl rubber composite barrier under planar biaxial tension. In simulation of externally applied physical strain during the usage of protective clothing, biaxially-stretched barrier specimens were exposed to the challenging agent of 1,5-dichloropentane. The results of permeation tests indicated that the decrease of breakthrough time under external strain stems exclusively from the reduction of barrier thickness. On the other hand, the steady-state permeation rate of butyl rubber composite was found to be dependent on the level of tensile strain as well as the reduction of barrier thickness. Thickness dependence of steady-state permeation rate became greater with higher extension ratios. The observed pure strain effect on the permeability was further analyzed by estimating the values of diffusion coefficient and solubility. The diffusion coefficient of composite barrier system was found to be independent of the level of strain applied. However, the solubility of the system was clearly increased by the external strain. The phenomenon could be attributed to two possible mechanisms. First, external strain can increase equilibrium swelling of butyl rubber matrix and thereby raise the solubility of the system. Additionally, the application of external strain can induce local debonding of carbon black reinforcement from the matrix of composite barrier system. The formation of local debonding sites is expected to accelerate the permeation process, since the vacuoles created are accessible to the solvent uptake.
Determination of Pesticide Levels as the Result of Cross-Contamination During Laundering
Authors: Milikin C , Oakland BG , Hurwitz MD
Published: March 2009

This study investigated the pesticide cross-contamination that occurs during laundering. The effects of pesticide, water temperature, and fabric combination were examined. Pesticide soiled fabric samples were individually laundered along with the same weight fabric that had not been exposed to pesticides in an Atlas Launder-Ometer in a method to represent one home laundry cycle. Samples were individually extracted and analyzed using gas Chromatographie techniques. An analysis of variance procedure was used to test for the main effects and interactions of the main effects. All main effects were significant at the 0.01 level. Further examination of all possible pair-wise comparisons of treatment means was carried out with a Duncan's multiple range post hoc procedure. Cross-contamination of pesticide residue was found to be dependent on pesticide with individual pesticides exhibiting different patterns of residue transfer. Laundry conditions and fabrics that allow for greater removal of pesticide residue provided an opportunity for more pesticide to be transferred to other fabrics.
Barrier Efficiency of Protective Clothing for Atrazine Production Workers
Authors: Oakland BG , Kim CJ , Schabacker DJ , Ross R
Published: March 2009

Protective suits made of two experimental nonwoven fabrics and a woven control fabric were worn by atrazine production workers to test barrier efficiency in a field situation. The nonwoven test suits were made of a spunbonded/meltblown/spunbonded polypropylene fabric with a liquid resistant finish and a wood pulp/polyester/spunlaced fabric with a fluorocarbon finish. A woven cotton suit was used as a control. Ten outside and ten inside cotton gauze patches were attached to the suit and analyzed for atrazine residues by a gas Chromatograph. The outside patches showed significantly higher residues than the corresponding inside patches in all three suits, suggesting that the protective clothing fabrics functioned as a barrier to the paniculate contaminants of atrazine. The residues extracted from the outside patches differed significantly by job functions for all three suits. The total barrier efficiency did not differ significantly among the three suits. It is suggested that fabrics designed to be resistant to particulates should be used in exposure to powdery contaminants.
Chlorpyrifos Decontamination Procedures for Clothing and Equipment
Authors: Perkins HM , Rigakis KB , Armour M-A , Crown EM , Kerr N
Published: March 2009

The safe clean-up of pesticide spills in the workplace and decontamination of equipment and clothing are important in minimizing pesticide exposure. The objectives of the research were: to develop a detoxification procedure for chlorpyrifos which would enable safe clean-up on the job site; to determine if a 3-hour chlorine bleach pretreatment of fabrics contaminated with dilute chlorpyrifos is as effective in pesticide removal from 65/35 polyester/cotton as from 100% cotton; and to determine whether the chlorine bleach pretreatment is effective for removal of concentrated chlorpyrifos residues. The researchers make specific recommendations for chlorine bleach detoxification of chlorpyrifos, and for use of a bleach/soak laundry protocol for removal of dilute chlorpyrifos from cotton and polyester/cotton. Concentrated chlorpyrifos cannot be effectively removed from either fabric by laundering.
Evaluation of Candidate Glove Liners for Reduction of Skin Maceration in Chemical Protective Gloves
Authors: Tremblay-Lutter JF , Lang JQ , Pichette D
Published: March 2009

After prolonged use of chemical protective gloves, excessive sweat build-up may lead to maceration of the skin. This study investigated various properties of glove liners that contribute to reduction of sweat accumulation. A test protocol was developed to evaluate the key properties of glove liners following a review of existing performance specifications and standard test methods. Eleven prototype gloves with various combinations of cotton, viscose, polyester microfibres and lycra were manufactured and evaluated to determine how glove liner properties could be optimized. Fabric mass and yarn density were also controlled to obtain a glove liner of approximately 1 mm in thickness with desirable moisture absorption, wicking, wettability and drying time. The viscose/polyester/lycra combination offered the optimum glove liner properties with a high moisture absorbency and short drying time. Lycra provided a better fitting liner without any significant detriment to the key properties.
Evaluating the Comfort Performance of Fabrics for Nuclear Protective Apparel
Authors: Barker RL , Scruggs BJ
Published: March 2009

The comfort properties of newly developed 100% nylon and 100% polyester fabrics are compared with materials that are currently used in nuclear protective apparel, including a 100% cotton and a polyester/cotton fabric. The Kawabata Evaluation System provided a highly sensitive measure of fabric mechanical and surface properties. A sweating skin model measured heat and moisture transfer properties under various conditions of heat and humidity. Laboratory screening tests were followed by extensive studies to determine actual human reactions to the comfort of the new nylon and control materials and garments. Results of controlled climate chamber wear trials confirmed the overwhelming importance of environmental and work levels on comfort ratings. Before sweat generating exercise and in a moderate environment (21°C, 65%RH), the comfort of nylon coveralls was clearly preferred over identically designed garments made with 100% polyester, and with heavier weight 100% cotton or polyester/cotton fabrics. The comfort rating of all test garments dropped dramatically as wearers were put through an exercise routine, and as test conditions were changed to produce a hot and humid environment (32°C, 90%RH). However, even under more stressful conditions, the comfort of the light weight nylon coverall was preferred over the controls in most cases. The higher absorption capacity of the cotton fabrics was beneficial in comfort comparisons made by the evaluators in a hot and humid environment.
Protective Textile Barrier Systems and Their Comfort
Authors: Shalev I , Barker RL , Hersh SP , Maini SM , Scruggs BJ , Sood VK , Tosti A , Tucker PA , Wu G
Published: March 2009

Protective and conventional fabrics are being investigated with emphasis on comfort as well as aerosol and chemical protection efficacy. Broad assault protection is assessed by measuring aerosol barrier efficiency using aerosolized polystyrene latex spheres and by measuring chemical protection using ASTM Standard Test Method for Resistance of Protective Clothing Materials to Penetration by Liquids (F-903) with acetone, methanol and sodium hydroxide solution. Comfort impact is assessed by the permeability index, im, which is the ratio of the thermal to evaporative resistance of the fabric normalized to the same ratio for still air. These data indicate that particulate penetration is a function of fabric structure and particle diameter. They verify the theoretically derived mechanisms by which fabrics trap particles in aerosols: larger particles are trapped by impact with fiber surfaces, while smaller particle penetration is governed by diffusion processes. Results of these tests define a “window of opportunity” where both barrier efficiency and permeability index might be jointly optimized for the benefit of the wearer.
Evaluating the Effectiveness of Different Laundering Approaches for Decontaminating Structural Fire Fighting Protective Clothing
Authors: Stull JO , Dodgen CR , Connor MB , McCarthy RT
Published: March 2009

Fire fighters are routinely exposed to thermal, chemical, biological, and physical hazards. Risk of exposure to thermal and physical hazards is limited to the fireground while the potential for exposure to chemical and biological hazards continues until contaminated clothing has been effectively decontaminated. This study characterized clothing contamination levels in retired fire fighter turnout gear and evaluated the effectiveness of current laundering practices in decontaminating this protective clothing.

Retired turnout coats, destructively evaluated using solvent extraction and gas chromatography with mass spectrometry, showed a variety of contaminants, some a significant concentrations. The relative effectiveness of six laundering techniques was determined against five materials using a technique to reproducibly contaminate and evaluate contaminant levels with six target chemicals. Dry cleaning was found to be the most efficient process for removing target contaminants while there was relatively little difference for most of the conventional laundering techniques. Force air circulation also provided effective in removing significant amounts of contamination. In addition, the effects of laundering procedures on clothing material performance were evaluated. The most significant changes was the reduction of water penetration resistance for a non-breathable moisture barrier material.
Injury Analysis: The Key to Improved Effectiveness of Protective Clothing
Authors: Laing RM , Wilson CA , Marshall SW
Published: March 2009

Selection of materials and clothing systems for protection of active firefighters in the workplace continues to focus on resistance to heat, flame, and chemicals. This is probably because these hazards are obvious and seem most likely to cause injury. However, examination of agents and events which actually result in injury is necessary if continued improvements to protective clothing systems are to be made. This rationale was explained in an earlier paper [1].

The present study sought to identify injury agents and types of injury sustained by New Zealand firefighters which resulted in hospital admission. Comprehensive national hospitalization files for a ten-year period 1980 – 1989 were examined. The World Health Organisation International Classification of Diseases E Codes were used to categorize injury events (agents) and included motor vehicles, water, poison, falls, fire and flame, suffocation and ‘other’. The International Classification of Diseases N Codes was used for injury diagnosis and included fractures, dislocation, sprains and strains, intra cranial, internal chest, open wounds, contusions, crushing, burns, nerves and spine, and toxic effects.

The highest injury rates per 1000 career employees occurred with fractures, toxic effects and open wounds, although no significant trends over time were observed. Falls and ‘other’ injury agents were the dominant cause of injury.

The rationale for current developments in protective clothing in New Zealand is explained, with reference to the diversity in the nature of work required of firefighters and to recent legislative changes.
CEN and ISO Standards for Protective Clothing Against Heat and Fire
Authors: Jung KP
Published: March 2009

The European Standardisation Committee (CEN) was commissioned by the European Community (EC) to elaborate a number of standards, among them standards for protective clothing against heat and fire. The EC-directive 89/686 stipulates only the basic requirements personal protective equipment has to satisfy. Harmonised standards defining technical safety requirements have to be set up at the European level to put these basic requirements into more concrete terms. The paper deals with the safety-relevant stipulations of European (EN) and International (ISO) standards for protective clothing against heat and fire; it provides information about the test methods used and about compliances between EN- and ISO-standards. The author compares safety requirements defined in EN-standards with those prescribed by the EC-directive and points out standardisation deficiencies.
Protective Clothing and Equipment Performance Requirements for Fire Service Urban Search and Rescue Teams
Authors: Stull JO , Connor MB , McCarthy RT
Published: March 2009

The protective clothing and equipment needs for emergency responders engaged in urban search and rescue activities were investigated. These activities involve areas of emergency rescue not undertaken as part of other traditionally defined response efforts such as fire fighting, hazardous materials response, and emergency medical services, and include, building collapses, trench cave-ins, flooding, and contaminated water diving. These incidents pose a variety of physical hazards, but also include fire contact, chemical exposure, prolonged exposure to adverse weather, contact with biological contaminants, and drowning. An Emergency Responder User Requirements Committee (ERURC) was formed to assist in the assessment of urban search and rescue protective clothing/equipment needs. The ERURC included representatives of the Fire Service and other groups experienced in urban search and rescue missions. Input from the ERURC, together with information obtained in industry surveys, was used to clearly define urban search and rescue missions, identify the needs of each mission, determine clothing and equipment to meet those needs, and propose generic performance requirements for clothing and equipment items. From these efforts, urban search and rescue protective ensembles were defined for three areas: (1) technical rescue, (2) swift water rescue, and (3) contaminated water diving. Similar protection needs and ensemble clothing/equipment needs were grouped. Specific design and performance requirements were defined for the clothing and equipment items in each ensemble.
Laboratory Equipment and Data Interpretation Method for Predicting Volatile Emissions During Solidification
Authors: Su HJJ , Jensen RH , Hinsenveld M
Published: March 2009

Volatilization is a valid concern in the solidification of wastes containing organics. In the presence of strongly adsorbing substances, however, even volatile compounds may not rule out solidification. In order to distinguish between wastes having negligible emissions and those from which emissions may be problematic, a definition of a “volatilization potential” and a method of determining this potential is needed. The assessment method can be based on the emission rate measured in a standardized laboratory setup.

This paper begins to develop a laboratory setup and a reference framework for the interpretation of the measured emissions from sludges. A “volatilization quality index” is derived, which can be used to evaluate and rank the potential of volatilization from sludges during mixing operations. This quality index is related to the measured emissions from an organic sludge taken from a waste site. The implications of the experimental results are related to practice.
Evaluation of Solidification/Stabilization for Treating Explosives Contaminated Soils
Authors: Cullinane MJ , Channell M
Published: March 2009

The success of solidification/stabilization (S/S) for treating explosives contaminated soils was evaluated using a variety of physical, chemical, and contaminant release testing methods. The analytes of concern included explosives and their degradation products (TNT, RDX, HMX, 2,4-Dinitrotoluene, 2,6-dinitrotoluene, 2,4,6-Trinitrotoluene, 2-Amino-4,6-Dinitrotoluene, 4-Amino-2,6-Dinitrobenzene, 2,4-Dinitrotoluene) and PAH's (Benzo(a)anthracene, Benzo(b)flouranthene, Benzo(k)flouranthene, Benzo(a)pyrene, Chrysene, Dibenz(a,h)anthracene, and Ideno(l,2,3-cd)pyrene). All Toxicity Characteristic Leaching Procedure (TCLP) leachate analytes, except 2-Am-4,6-DNT, were significantly reduced by S/S. All of the PAH compounds were reduced below detection limits. The release of 2,4,6-TNT was reduced approximately 97%. The release of 2,4-DNT was also significantly reduced. The results of the Sequential Batch Leach Test (SBLT) were mixed. The PAH compounds were not identified above detectable limits in the leachates from either the untreated soil or the treated soils. Release of 2,4,6-TNT was reduced to undetectable. However, other explosives related compounds (2-Am-4,6-DNT) were identified in the leachates from the treated soils that were not identified in the untreated soil. Organic transformations in the highly alkaline environment associated with S/S or sample heterogeneity are suspected to cause this phenomena.
Immobilization of Low Level Hazardous Organics Using Recycled Materials
Authors: Conner JR , Smith FG
Published: March 2009

Rust Remedial Services, Inc. (RRS) recently conducted a major study on the effectiveness of additives, both virgin and recycled, in the immobilization of low-level organics in soils. Using a clean soil spiked with a mixture of hazardous organic chemicals, twelve different stabilization formulations were comparatively tested using leaching (TCLP) and total analysis (TCA) methods. TCLP reduction levels illustrated the effectiveness of the stabilization treatment on a wide variety of low level organics in contaminated soil, with the proper selection of stabilization admixtures. A specially prepared, comminuted, rubber particulate was especially effective in reducing the apparent presence of certain semi-volatile organic compounds in soil, as measured by TCA methods. Most semi-volatile organic compounds were so strongly held by the rubber particles that they were not recovered in the analytical procedure.
The Effect of Graphite Venting on ISV Processing of Low Permeability Soils
Authors: Gardner BM , Farnsworth RK
Published: March 2009

In situ vitrification (ISV) is a promising technology for remediating buried waste and contaminated soil sites. Concerns exist, however, that low soil permeabilities may limit vapor transport away from the advancing ISV melt front, causing a melt expulsion that breaches ISV containment. A potential solution may be the use of a graphite rod placed vertically through the area being processed, which acts as a “preferred pathway” in venting generated vapors through the ISV melt. To evaluate this engineering solution, two ISV lab tests were conducted at the Idaho National Engineering Laboratory, using a low permeability clay material. One of the tests used the graphite rod concept, while the other did not. Test results found that the graphite rod is effective in preventing the buildup of pressures beneath the ISV melt. The graphite rod may also limit the amount of entrained particulate released to the offgas system during ISV processing.
Thermoplastic Encapsulation Treatability Study for a Mixed Waste Incinerator Off-Gas Scrubbing Solution
Authors: Kalb PD , Adams JW , Meyer ML , Burns HH
Published: March 2009

A bench-scale study was conducted to evaluate thermoplastic encapsulation as a treatment for an aqueous blowdown mixed waste to be generated at the Consolidated Incineration Facility (CIF) at the Savannah River Site. Non-radioactive CIF blowdown surrogate, dried in a stirred vacuum dryer, was stabilized at relatively high waste loadings (45 – 62 wt%) using modified sulfur cement, bitumen, and low-density polyethylene. All samples tested exceeded 3.45 MPa (500 psi) in compressive strength, and water immersion for 90 days did not produce any adverse impacts on waste form integrity. In each case, ignition temperature was well above the process temperature, and the materials self extinguished when cooled below the self ignition temperature. Leachability of toxic metals from simulated waste encapsulated in polyethylene was about 4 times lower than modified sulfur cement or bitumen test samples. Polyethylene waste forms containing up to 35 wt% pretreated waste easily passed EPA land disposal regulation limits.
Flow-Through Leach Testing Applied to Stabilized/Solidified Wastes
Authors: Butcher EJ , Cheeseman CR , Sollars CJ , Perry R
Published: March 2009

One of the fundamental requirements for assessing the suitability of cement-based Stabilization/Solidification as a method for the safe disposal of hazardous materials is the manner in which they will release contaminants over an extended period of time. In this paper the leaching of a synthetic Stabilized/Solidified waste, of composition similar to wastes produced from a commercial process in the United Kingdom are investigated under conditions in which leachant flows through the connected porosity of the sample. The leaching of Zn, Cd, Hg, Pb, Cu, Ni, Fe and Cr has been determined using a modified triaxial cell (flexible wall permeameter). Analysis of unleached solidified waste samples using XRD indicated retardation of conventional cement hydration reactions. The principal crystalline phases observed were ettringite and calcite. Leaching carried out using RO purified water used to simulate a mono-disposal situation, indicated that sufficient buffering capacity remained in the solidified materials to limit the release of all elements except Hg to less than 1% of the total. The leaching of mercury appeared to be related to that of calcium. In this experiment approximately 3600 sample volumes of RO water were passed through the solidified waste. In a second series of experiments (pH=2.88) acetic acid, designed to simulate co-disposal conditions was passed through samples. The acid buffering capacity was found to be insufficient to allow retention of metals after only 50 sample volumes. The order of leaching in this case was found to be Cd > Zn > Cu = Ni > Pb > Hg > Cr > Fe. From this possible retention mechanisms for specific elements are reviewed. In these experiments the total volume of leachate collected was approximately 600 sample volumes. It is believed that this technique has a significant potential for usage in the leach testing of monolithic Stabilized/Solidified waste samples.
Experimental and Theoretical Studies for Assessing the Retention Capacity of Cement Stabilized Materials for Land Disposal
Authors: Balzamo S , Castellano L , De Angelis G
Published: March 2009

An extensive study was carried out on the release of different contaminants from cement stabilized wastes. The goal of the work was to make a computer code, called RECOSTA (RElease of COntaminant from cement STAbilized wastes), to support (i) the comprehension of the chemical-physical phenomena which govern the leachability of various elements (to choose the best composition for the immobilization matrix) and (ii) the definition of the protocols for monitoring and controlling of the release of pollutants (which occurs when hazardous waste are disposed of in a landfill). To this end the following toxic elements, incorporated in different cement based systems, were leached according to ANSI/ANS 16.1: Cs(I), Cd(II), Co(II), Cu(II), Pb(II), Sr(II), Zn(II), Cr(III), Fe(III), Cr(VI).