气溶胶态生物粒子检测下限和响应时间的实验测定

Experimental measurement of the detection limit and response time for a bio-aerosol detection instrument

气溶胶态生物粒子的检测下限和响应时间是生物气溶胶荧光检测设备的2项重要指标。介绍一种空气中生物气溶胶浓度的检测方法,利用纯净空气在缓冲瓶中稀释发生的模拟生物气溶胶粒子浓度,稀释后的气溶胶一路进入光学颗粒物粒径谱仪,测量结果作为标准计数,另一路进入气溶胶检测设备完成测定。结果表明,所设计生物气溶胶荧光检测设备对纯净空气和真实空气中浓度<1 000/L的生物气溶胶粒子均具有较高检测灵敏度,响应时间<1 min。这对于空气中生物气溶胶粒子或其他粒子的计数测量及仪器标定具有一定借鉴意义。

Detection limit and alarm response time of bio-aerosol particles are two important indicators for bio-aerosol real-time detection instrument based on intrinsic fluorescence measurement. A method for detecting the concentration of bioaerosols in the atmosphere is presented. Firstly, pure synthetic air was used to dilute the simulated bio-aerosol particles, and then, the diluted simulated bio-aerosol particles were discharged by two pipelines, one was inhaled into the optical particle sizer spectrometer（model TSI-3330） for standard count of bio-aerosol particles, and the other was inhaled into the bio-aerosol real-time detection instrument for testing its indicators. Testing results show that our bio-aerosol real-time detection instrument is sensitive to the bio-aerosol particles, at 1 000/L level, both in pure synthetic air and in the real atmosphere. In particular, its alarm response time is less than one minute. This is valid for the calibration of bio-aerosol real-time detection instrument, and may also be adopted for counting measurement of bio-aerosol or other particles.