Cascade-Impactor 30 LPM, TE-30-500
|
Cascade Impactor 5LPM, TE-05-500
|
Cascade Impactor, Viable Impactor and Microbial Sampler, TE-10-800
|
Cascade Impactor, TE-20-800
|
 |
Cascade Impactors
|
In conjunction with the Harvard School of Public Health, Tisch Environmental Inc. is now able to offer a unique series of cascade impactors. These instruments have the ability to fractionate aerosols by size and gather significant amounts of particles onto small, inert impaction substrates without the use of adhesives.
Consistent with the above, we are offering the 5 LPM version as well. This instrument still features the ability to fractionate aerosols by size and gather significant amounts of particles onto small, inert impaction substrates without the use of adhesives.
Our Viable Particle sampler consists of six aluminum stages assembled together by 3 spring clamps. Each stage is sealed with an "O" ring. In addition, each impactor stage has multiple precision orifices. When air is pulled by vacuum through the instrument, air is directed through a series of jets which direct airborne particles toward the surface of the agar collection surface of that specific stage. The dimension of the jet is constant within each stage and are progressively smaller in the next stage. The range of particle sizes collected is deteremined by the jet velocity and the cutoff of the previous stage. Particulate not collected on the first stage will continue to move through the air as it diverts around the rim of the Petri dish to the next stage.
This series of Cascade Impactors is designed for ambient air applications in the case where Non-Viable (Non-Biological) aerosols are collected and measured for concentration by aerodynamic particle size. This concentration is calculated by weighing the 81mm sample substrates both before and after. The substart is located below each Orifice Stage. As particulate progressively passes through smaller diameter orifices the samples experience acceleration. As the aerosol exits each of the orifices it will divert around the impaction substrate. The particles that have an aerodynamic diameter and addionally an inertia that can not stay in the sample air flow will break free from the stream of air and collect by impact onto the sample substrate. By making the orifice diameter smaller on each Stage of the Cascade Impactor, the particles will increase in speed and the aerodynamic separation of particles over a large range can be determined.Copyright (c) 2011 Cascade-Impactors.com. All rights reserved. |