The Sampling Efficiency of Personal Inhalable Aerosol Samplers in Low Air Movement Environments

A compact, low cost, and easy to operate experimental system was developed for evaluating personal samplers in a calm-air environment. The system can provide uniformly distributed monodisperse microspheres up to 69.7 µm in a quiescent environment for determining sampler efficiencies using a fluorescence method. The reference concentration was measured using one vertical and two horizontal sharp-edged probes. The vertical sampling probe met the criterion for greater than 90% sampling efficiency for upward facing cylindrical probes given by Agarwal and Liu, except at the particle size of 69.7 µm. In addition, the consistent agreement among all three reference sampling probes at all particle sizes tested implied that representative measurements of aerosol concentrations in the test section were achieved. In this study, the RespiCon (Model No. 8522, TSI Inc., St. Paul, MN, USA) and IOM (Cat. No. 225-70, SKC Inc., Eighty Four, PA, USA) personal aerosol samplers were evaluated in the system with air velocities in the sampling region below 1.5 cm/s. The sampling efficiency of the IOM was near 100% at all particle sizes, while the RespiCon matched the conventional respirable and thoracic convention curves but undersampled the inhalable fraction.

“…5. Since Kenny et al (1999) found similar results with and without a manikin present in the test chamber, valid tests can be performed without a manikin present.…”

Section: Introductionmentioning

confidence: 55%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Design and Use of a Settling Chamber for Sampler Evaluation Under Calm-Air Conditions

Feather

Chen

2003

“…For example, to name only a few, the following have done work in wind tunnels: Badzioch (1959), Belyaev and Levin (1972), Ogden and Birkett (1977), Mark and Vincent (1986), Okazaki et al (1987), Aizenberg et al 597 (2000a, b), and Li and Lundgren (2002). There have been fewer experiments conducted in calm-air chambers, including Davies (1968), Breslin and Stein (1975), Kenny et al (1999), and Feather and Chen (2003).…”

Section: Introductionmentioning

confidence: 99%

Use of Numerical Calculations to Simulate the Sampling Efficiency Performance of a Personal Aerosol Sampler

Bird

2005

Numerical calculations were conducted to simulate air and particle behavior near and into the inlet of an aerosol sampler in order to determine sampling efficiency performance. This was done with the pre-verified commercial computational fluid dynamics (CFD) software package, FLUENT (Fluent, Inc., Lebanon, NH, US). Air flow behavior was calculated for steady-state conditions approaching and flowing into 3D geometries of an aerosol sampler free in the air that was similar in dimension to two commercial samplers, namely the Gesamtstaubprobenahme sampler (GSP) and the conical inhalable sampler (CIS). Particle trajectories were calculated in a Lagrangian reference frame on the resulting velocity fields. Based on the particle trajectories, sampling efficiencies were calculated and compared to those reported in the literature for a CIS aerosol sampler. They were found to have similar overall trends for particle sizes up to 21 µm. Using a correction factor, agreement The findings and conclusions in this report are those of the author and do not necessarily represent the views of the Centers for Disease Control and Prevention or the National Institute for Occupational Safety and Health. Mention of a commercial product or trade name does not constitute endorsement by the Centers for Disease Control and Prevention or the National Institute for Occupational Safety and Health.Address correspondence to Aaron J. Bird, M/S 3030, Exposure Assessment Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, 1095 Willowdale Road, Morgantown, West Virginia 26505, USA. E-mail: ABird@cdc.gov was observed to be very good for smaller particles, but less so for larger particles.

“…As the role of personal monitors in assessing personal exposure to PM increases, it is important to evaluate these monitors' effectiveness and accuracy (Aizenberg et al 2000;Bradley et al 1994;Kenny et al 1997;Ramachandran et al 1998;Witschger et al 1998). The results reported here focus on the use of passive sampling nephelometers in various situations ranging from low-speed undisturbed ow to the recirculating ow region in a person's wake.…”

Section: Introductionmentioning

confidence: 99%

On the Impact of the Human (Child) Microclimate on Passive Aerosol Monitor Performance

Eisner¹,

Heist²,

Drake³

et al. 2002

Research into the wind microclimate and its effect on the accuracy and effectiveness of passive aerosol monitors is expanding as the importance of personal monitoring versus regional monitoring increases. The important phenomena for investigation include thermal and dynamic effects of the human body, contaminant dispersion around a human body and within a building complex, and the wind environment within a building (indoor/outdoor) complex. This paper demonstrates that the microclimate around the human body plays a critical role in contaminant transport near the body and thus can affect particle concentration measurements by personal samplers.