Abstract: A wet-film particle impactor includes a housing, a nozzle, an impact surface and at least one water inlet. The housing defines a chamber therein and has an air outlet and a water outlet. The nozzle is disposed on the housing and has a plurality of through holes in communication with an air inlet and the chamber. The water inlet is formed on the impact surface for introducing water into the chamber. Whereby, the wet-film particle impactor is adapted to introduce the particle-containing air stream into the chamber sequentially via the air inlet and the through holes. The particles in the air stream are collected by the impact surface. The water introduced from the water inlet flushes the impact surface, carries the particles collected by the impact surface, and then exits the chamber via the water outlet.

Abstract: A portable nanoparticle sampler for collecting respirable particulate matters and nanoparticles is composed of a tangential flow cyclone, a multi-microorifice impactor and a filter cassette. The tangential flow cyclone can remove the microparticles with cutoff aerodynamic diameter (dpa) larger than 4 ?m and guide the airflow to the multi-microorifice impactor located below the cyclone. The multi-microorifice impactor includes a multi-orifice nozzle and a rotary impaction plate for enabling the microparticles with dpa from 100 nm to 4 ?m to be uniformly collected on a silicone-oil-coated impaction substrate. The remnant microparticles with dpa smaller than 100 nm are collected by the filter cassette. Therefore, compared with the prior art, the portable nanoparticle sampler is characterized by low pressure loss and accurate microparticle sizing to meet the requirement of nanoparticle sampling at workplaces.

Abstract: A portable nanoparticle sampler for collecting respirable particulate matters and nanoparticles is composed of a tangential flow cyclone, a multi-microorifice impactor and a filter cassette. The tangential flow cyclone can remove the microparticles with cutoff aerodynamic diameter (dpa) larger than 4 ?m and guide the airflow to the multi-microorifice impactor located below the cyclone. The multi-microorifice impactor includes a multi-orifice nozzle and a rotary impaction plate for enabling the microparticles with dpa from 100 nm to 4 ?m to be uniformly collected on a silicon-oil-coated impaction substrate. The remanent microparticles with dpa smaller than 100 nm are collected by the filter cassette. Therefore, compared with the prior art, the portable nanoparticle sampler is characterized by low pressure loss and accurate microparticle sizing to meet the requirement of nanoparticle sampling at workplaces.