Lillo R S, Morris J W, Caldwell J M, Balk D M, Flynn E T
Naval Medical Research Institute, Diving Medicine Department, Bethesda, Maryland 20814-5055.
Undersea Biomed Res. 1990 Sep;17(5):437-51.
The Naval Medical Research Institute currently conducts hyperbaric research in a Man-Rated Chamber Complex (MRCC) originally installed in 1977. Significant engineering alterations to the MRCC and rusting of some of its interior sections necessitated repainting, which was completed in 1988. Great care was taken in selecting an appropriate paint (polyamide epoxy) and in ensuring correct application and curing procedures. Only very low levels of hydrocarbons were found in the MRCC atmosphere before initial pressurization after painting and curing. After pressurization, however, significant chemical contamination was found. The primary contaminants were aromatic hydrocarbons: xylenes (which were a major component of both the primer and topcoat paint) and ethyl benzene. The role that pressure played in stimulating off-gassing from the paint is not clear; the off-gassing rate was observed to be similar over a large range in chamber pressures from 1.6 to 31.0 atm abs. Scrubbing the chamber atmosphere with the chemical absorbent Purafil was effective in removing the contaminants. Contamination has been observed to slowly decline with chamber use and is expected to continue to improve with time. However, this contamination experience emphasizes the need for a high precision gas analysis program at any diving facility to ensure the safety of the breathing gas and chamber atmosphere.
海军医学研究所目前正在一个最初于1977年安装的载人舱室综合体（MRCC）中进行高压研究。MRCC进行了重大工程改造，其部分内部区域生锈，因此需要重新喷漆，这项工作于1988年完成。在选择合适的油漆（聚酰胺环氧树脂）以及确保正确的涂装和固化程序方面都格外小心。在喷漆和固化后首次加压前，在MRCC环境中仅检测到极低水平的碳氢化合物。然而，加压后发现了严重的化学污染。主要污染物是芳烃：二甲苯（底漆和面漆的主要成分）和乙苯。压力在促使油漆释放气体方面所起的作用尚不清楚；在舱内压力从1.6绝对大气压到31.0绝对大气压的较大范围内，观察到气体释放速率相似。用化学吸收剂Purafil洗涤舱内空气能有效去除污染物。随着舱室的使用，已观察到污染在缓慢下降，预计随着时间推移还会继续改善。然而，这次污染事件强调了任何潜水设施都需要一个高精度气体分析程序，以确保呼吸气体和舱内空气的安全。
