防放射性微粒呼吸器泄漏率测试装置

A DEVICE FOR MEASURING LEAKAGE RATE OF RESPIRATORS AGAINST RADIOACTIVE PARTICULATES

本文介绍了一套检定防放射性微粒呼吸器泄漏率的测试装置。它由空气干燥净化、试验尘发生和采样检测三部分组成。试验生选用粒径为0.3μm的单分散相聚苯乙烯粒子。本装置粒子发生浓度稳定、可调,与国外同类标准测试方法有一定的可比性,最小可测泄漏率为0.01％。文中还对非等速采样和粒子在采样管道内的沉积等因素所引起的粒子计数误差作了分析。

This paper describes a device, for measuring protection.performance of respirators against radioactive particulates.The device consists of three parts: air cleaning, test dust generatingand monitoring. Monodispersed polystyrene latex particleswere used in this measurement as standard artificial test dustParticles were generated by a ultrasonic atomizer and were dilutedwith clean air which was filtered with a high efficiency filterThe mean diameter of particles was 0.3μm, the geometric standarddeviation (σ_g) less than 1.1. The concentration and quantity ofthe test dust Were stable and controllable. The device has themaximum detectable protective efficiency of 99.99% or the minimumdetectable leakage rate of 0.01%. The protection performance tests,onrespirators and filter media showed the good stability and reproducibilityof the device. The factors resuled in counting errors are also analyzedin the paper, such as non-isokinetic sampling and deposition insampling conduits.