Improved Respirator Carbons for Ammonia Hazards

 描述（由申请人提供）：TDA Research，Inc. (TDA)建议开发新型活性炭，以保护70多万农业工人，根据疾病预防控制中心的说法，他们面临着接触有毒氨的风险。除了农业工人，消防队员，急救人员和化学工业人员也处于危险之中。OSHA将空气中300 ppmv的NH3列为对生命和健康有直接危险（IDLH）。150 ppmv的水平导致肺组织永久性疤痕，引起慢性呼吸道疾病。氨易溶于水，损害身体的潮湿组织，尤其是眼睛。最初的眼组织损伤和坏死引起的氨往往其次是结膜炎和继发性眼部感染。长期暴露在6 ppmv的浓度下也会导致眼睛损伤和暂时失明，高浓度则会导致永久失明。例如，在超过257，000个动物饲养操作（AFO）和超过15，500个集中动物饲养操作（CAFO）的通风不良的建筑物中，NH3水平通常超过50 ppmv，并且冬季通风率低，农业工人通常暴露于100-200 ppmv。公共卫生倡导者建议，在氨释放作业的顺风处，儿童不应暴露在超过300 ppbv的空气中。过去，工人们一直依赖于含有活性炭的制冷机，活性炭是从椰子壳的热解中产生的，这是一种为第一次世界大战防毒面具开发的技术。然而，其中最好的最近已经停产，使得氨净化器制造商争先恐后，迫切需要专门用于氨净化器的活性炭的新供应。大多数现成的活性炭，设计用于其他目的，是无效的， NH3吸收。TDA的员工在特种吸附剂的设计方面拥有20多年的经验，每年为全球客户提供100多吨。在初步研究中，TDA已经证明，与目前可用的活性炭相比，经处理的活性炭在NH3吸收方面表现得更好。在第一阶段，碳将被优化用于NH3吸收。在第二阶段，碳将扩大规模以实现商业化。

 DESCRIPTION (provided by applicant): TDA Research, Inc. (TDA), proposes to develop new types of activated carbons to protect the more than 700,000 agricultural workers, who according to the CDC are at risk from exposure to toxic levels of ammonia. In addition to agricultural workers, fire fighters, first responders and chemical industry personal are also at risk. OSHA rates 300 ppmv NH3 in air as Immediately Dangerous to Life and Health (IDLH). Levels of 150 ppmv have led to permanent scarring of lung tissue causing chronic respiratory illness. Ammonia readily dissolves in water and damages moist tissues of the body, and especially the eyes. Initial eye-tissue damage and necrosis caused by ammonia is often followed by conjunctivitis and secondary eye infection. Chronic exposure to even 6 ppmv has caused eye damage and temporary blindness, and high levels have caused permanent blindness. In poorly-ventilated buildings of the over 257,000 Animal Feeding Operations (AFO) and the over 15,500 Concentrated Animal Feeding Operations (CAFO), for example, NH3 levels routinely exceed 50 ppmv, and with low winter-ventilation rates, agricultural workers are often exposed to 100-200 ppmv. Advocates of public health are recommending that children down-wind of ammonia-releasing operations should not be exposed to more than 300 ppbv NH3 in air. Hitherto, workers have relied on respirators incorporating activated carbons produced from pyrolysis of coconut shell-a technology developed for World War I gas masks. However, the best of these has recently been discontinued, leaving manufacturers of ammonia respirators scrambling and with a critical need for new supplies of activated carbons that are specific for use in ammonia respirators. Most off-the-shelf activated carbons, designed for other purposes, are ineffective for NH3 uptake. Staff at TDA has over 20 years of experience in the design of specialty sorbents, supplying over 100 metric tons per year to customers, worldwide. In preliminary studies, TDA has demonstrated that a treated activated carbon performs significantly better for NH3 uptake compared to activated carbons now currently available. In Phase I, the carbons will be optimized for NH3 uptake. In Phase II, carbons will be scaled up for commercialization.