Lead is a hazardous material and US congress has mandated the rapid reduction of all hazardous waste generation as a matter of national policy. With the large amount of plutonium handling in numerous projects including the development of MOX fuel, power source etc., hand glove protection for the emitted alpha-beta- and low energy photons is an important issue. Leaded gloves are the prime shields used for radiological hand protection. US Department of Energy laboratories require a substitute material for the lead oxide in the gloves, as a way to reduced mixed waste. To solve this problem, a new blend of non-hazardous materials that have the same radiological properties, approximately the same cost of production, and lastly not potentially fall under the Resource Conservation and Recovery Act (RCRA) regulation, to replace the lead oxide currently used in the gloves had been investigated. The investigations have produced alternative materials using calculations (deterministic and Monte Carlo, MCNP) and experiments. The selection of the constituent compounds for the new composite materials, were based on the k-absorption edge energy of the main constituent element(s) in the compound. The formulations of these composites were fashioned on the principle of blending neoprene rubber formulation with several constituent compounds. Calculations based on the Lambert-Beer attenuation law together with the mass attenuation coefficient values from the XCOM cross section database program were used to determine the transmission fractions of these proposed composite materials. Selected composite materials that compared favorably with the leaded-neoprene were fabricated. These fabricated composite materials were tested with attenuation experiments and the results were in excellent agreement with the calculations using the Lambert-Beer law. For the purpose of benchmarking the result of the calculations, Monte Carlo calculations were also made. The success of this research would mean that this new composite material could also replace the lead aprons currently in use, as shields against radiation like x-ray in most hospitals. Based on computational and experimental results, the recommended compositions of the composite materials for the glove are: (i) Erbium III Oxide (Er2O3)—40% and 40 Tungsten Boride (WB) blend with 20% Neoprene formulation, or with the reduced Er2O3, (ii) Erbium III Oxide (Er2O 3)—5% and 75% Tungsten Boride (WB) blend with 20% Neoprene formulation. (iii) Tungsten III Oxide (WO3)—80% blended with 20% Neoprene formulation. Toxicity Characteristic Leaching Procedure (TCLP) results show that, several heavy metals used in these new materials that would leach out were below the US EPA limit or are not on the list of regulated heavy metals. However, on the original gloves Lead leached out at a concentration of 5.2 mL/L, slightly above the regulatory limit.
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机译：铅是一种有害物质，美国国会已根据国家政策要求迅速减少所有危险废物的产生。随着许多项目中大量handling的处理，包括MOX燃料，电源等的开发，针对所发射的α-β-和低能光子的手手套保护是一个重要的问题。含铅手套是用于放射防护手部的主要防护罩。美国能源部实验室要求在手套中使用氧化铅的替代材料，以减少混合废物。为了解决这个问题，使用一种新的无害材料混合物来替代目前的氧化铅，这些混合物具有相同的放射线特性，大约相同的生产成本，并且最终不属于《资源保护和回收法》（RCRA）的规定。在手套中使用过的已经过调查。研究使用计算（确定性和蒙特卡洛，MCNP）和实验产生了替代材料。基于复合材料中主要组成元素的k吸收边能量来选择新复合材料的组成化合物。这些复合材料的配方是根据氯丁橡胶配方与几种成分的混合原理制成的。基于Lambert-Beer衰减定律的计算以及XCOM横截面数据库程序的质量衰减系数值被用于确定这些建议的复合材料的透射率。所制造的复合材料与铅-氯丁橡胶相比具有优势。这些合成的复合材料通过衰减实验进行了测试，其结果与使用朗伯-比尔定律进行的计算非常吻合。为了基准化计算结果，还进行了蒙特卡洛计算。这项研究的成功将意味着这种新的复合材料还可以替代目前使用的铅皮圈，作为大多数医院中防止X射线等辐射的屏蔽物。根据计算和实验结果，建议用于手套的复合材料的成分为：（i）III氧化Ox（Er 2 O 3 ）— 40％和40硼化钨（WB）与20％氯丁橡胶配方或还原的Er 2 O 3 掺混物，（ii）III氧化E（Er 2 O 3 ）-5％和75％的钨化钨（WB）与20％的氯丁橡胶配方混合。 （iii）III氧化钨（WO 3 ）-80％与20％氯丁橡胶配方混合。毒性特征浸出程序（TCLP）结果表明，这些新材料中使用的几种重金属会浸出，其含量低于美国EPA限值或不在受管制的重金属清单中。但是，在原始手套上，铅的浸出浓度为5.2 mL / L，略高于法规限值。
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