Choosing at Optical Particle Counter

In theory, on optical particle more counter utilizes A light SOURCE, typically A laser diode, ton illuminate A selected SAM-polarizes OF air that has mechanically control LED flow through A precisely configured nozzle known as isokinetic rehearses on. As lakes into the diagram, the light beam is positioned RK fishes on tons the air SAM-polarizes. A photodetector then measures the light elastically scattered off the particles by reflection, refraction and diffraction. Based on the intensity OF the flash, particles CAN fuel element counted and sized RK the same time. It is important tons of note that the physical properties OF the particles CAN have on effect on the light scattered as various material absorb light RK different advice which wants affect the intensity OF the light scattered. There of acres several variable involved with selecting the optimum particle more counter for various applications. - Resolution - the smallest particle size difference that CAN fuel element detected. - Sensitivity - the smallest particle that CAN fuel element � lakes � RK A particular COUNTING efficiency POINT. - COUNTING Efficiency - the particle concentration that CAN fuel element � lakes � by at instrument against the true particle concentration as measured by A more sophisticated or calibration quality means. - Precision - the standard deviation OF measurements OF the same sized particles. - Repeatability - the extent ton which at instrument wants give the same response particle conditions airborne into size and COUNT ton control LED or known over time. Ton keep instrument reasonably portable, most optical particle counters have A of lower limits rank OF about 0,3 microns. This is due ton the intensity OF the lasers light SOURCE in A limited size configuration. Instrument typically COUNTs in two tons six size of rank or � bins � in near real-time. Most of acres battery operated with at option ton of run off AC power with on electrical adapters. Costs rank from A few thousand dollars for Handheld unit ton tens OF thousands OF dollar for sophisticated laboratory degrees of instrument. Manufacturers typically recommend annual calibration for reliable operation. High flow counters, typically 1 cfm or 28,3 L/min. of more offer advantages in certain situation. There of acres even some 2 cfm (nominally) or 50 L/min. unit on the market. The high flow guesses/advises instrument of acres for where A large volume OF air to conditions needs tons of fuel element analyzed. Usually the particle size resolution is reduced and the ability ton detect small particles is reduced due tons of A decreased signal ton noise reason. Thesis unit, though considered portable, tend tons of fuel element somewhat bulkier and of heavier ton accommodate the larger volume pumps and of batteries ton support operation. Low flow counters, typically 0,1 cfm or 2,83 L/min. of offer CLEARs of advantages where less air volume is needed look for as in spot checks. The lower flow guesses/advises allows for more smaller particles ton to fuel element detected as they acres into the viewing window more longer. This thus allows for more higher concentrations tons of fuel element measured. Many OF thesis low flow of instrument of acres Handheld, lightweight and battery operated. Applications where particle size and COUNT of acres needed include: - Aerosol research Industrial hygiene personnel exposure monitoring indoor air quality assessment Environmental of studies looks for as EPA compliance Verifying rem oval efficiency in filter or air cleaners Process concentration fluctuation Particle SOURCE identification Yield improvement into precision manufacturing processes Verifying equipment performance as in building management meeting specification looks for as air filter ratings meeting regularization or certification as with cleanrooms, safety cabinets, fume hoods or Clearance verification assurance in pharmaceutical preparation quality look for as HVAC system cleaning Verifying environmental controls search as paint booth exhaust monitoring particle migration from construction or remodellingSelecting the optimum particle more counter for A given application depends on the importance OF thesis situational conditions. A person May choose ruggedness and long term repeatability more over precision when doing environmental studies, for example. While of another person May elect sensitivity and efficiency in A highly sensitive semiconductor manufacturing AREA where even slight fluctuations in ambient conditions May greatly impact quality and yield.

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