高效空气过滤器现场检漏方法测试精度比较研究

Comparative Studies of Test Precision of In-situ Leak Test Methods for High Efficiency Particle Air Filters

本文针对高等级生物安全实验室中绝大多数屏障隔离设施排风高效过滤器不能用扫描法检漏而只能采用低精度的全效率法检漏的现状,及其实际应用困难,采用实验方法对钠焰法、光度计法和计数法在检漏测试中的应用可行性、全效率检漏与扫描检漏测试精度差别及复杂现场条件对全效率检漏的影响进行了研究。研究结果表明：3种检测方法对有漏孔高效过滤器的测试结果基本相当,其中,局部透过率相对偏差大都在1.3%~13.3%之间,整体透过率相对偏差大都在4.5%~22.2%之间。全效率法与扫描法测试结果差异明显,同一漏孔滤器整体透过率仅为局部透过率的2.4%~6.1%,而过滤器下游弯头或风机的存在进一步导致整体透过率衰减为局部透过率的0.9%~4.6%。

In high-level biosafety Laboratories,most exhaust HEPA filters of the primary barrier facilities could not be accessible for scanning leak tests. The low-precision total penetration leak tests become the only choice for users. According to such situations and the applicable difficulties,this paper adopts experimental methods to study the feasibility of sodium flame method,aerosol photometer method and particle counting method in leak tests,and the difference of test precision between total penetration leak test method and scanning leak test method. The influence of complicated field conditions on total penetration leak test method is studied as well. The research results show that the three detection methods have similar test results for HEPA filters with leak holes. The local penetration ratio relative deviation among the three detection methods is between 1. 3% and 13. 3%,and the overall penetration ratio relative deviation is between 4. 5% and 22. 2%. Significant differences of test results are formed between total penetration leak test method and scanning leak test method. For the same leak point,the overall penetration ratio is only 2. 4% ~ 6. 1% of the local penetration ratio. Moreover,the presence of the elbow or fan at the downstream of the filter makes the overall penetration ratio drop to 0. 9% ~ 4. 6% of the local penetration ratio.