Calibration and evaluation of a real-time cascade impactor

Journal Article · Sun Apr 01 04:00:00 EST 1984 · Am. Ind. Hyg. Assoc. J.; (United States)

DOI:https://doi.org/10.1080/15298668491399668· OSTI ID:5864809

Fairchild, C I; Wheat, L D

A 10-stage cascade impactor made by California Measurement Inc., can determine aerodynamic size distributions of dilute aerosols in a few minutes. Collection of impacted particles on greased, vibrating piezoelectric crystals produces changes in vibrational frequency proportional to the collected mass. Based on frequency changes and sampling time, a data reduction module calculates the mass collected on each stage. Calibration of the assembled impactor was performed with monodisperse polystyrene latex (PSL) and Eosin-Y (E-Y) aerosols for the lower stages (4-10), and PSL and pollen particles (ragweed and mulberry) for the upper stages (1-3). The stage experimental effective cutoff aerodynamic diameters (ECAD) were up to 22 percent different from theoretical ECADs with the exception of Stages 1 and 2 which were respectively 30 and 35 percent different from theoretical ECADs. The overall loss of particles > 3- and < 0.3-..mu..m was severe. Also, considerable scatter of particles was observed on the collection crystals of Stages 1 and 2. Although a majority of particles were in the impaction area, a large fraction was scattered over the outer portions of these crystals.

• Research Organization: Los Alamos National Lab., NM
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5864809
• Journal Information: Am. Ind. Hyg. Assoc. J.; (United States), Journal Name: Am. Ind. Hyg. Assoc. J.; (United States) Vol. 45:4; ISSN AIHAA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring &amp; Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOL MONITORING
AIR POLLUTION MONITORING
CALIBRATION
CASCADE IMPACTORS
CLASSIFICATION
DATA
ELECTRICITY
EVALUATION
EXPERIMENTAL DATA
INFORMATION
MASS
MONITORING
NUMERICAL DATA
PARTICLE SIZE
PARTICLES
PARTICULATES
PIEZOELECTRICITY
REAL TIME SYSTEMS
SIZE