The Effect of Sampling Time on the Overall Performance of Portable Microbial Impactors

Figures & data

TABLE 1 Physical characteristics of tested portable microbial samplers

Sampler	Sampling flow rate, L/Min	Number of impaction nozzles	Experimental d 50, μ m	Agar volume, mL
BioStage	28.3	400	0.65	50
SMA	141.5	12	4.8	25
BioCulture	120	380	7.0	30
MAS-100	100	400	1.7	50
Microflow	120	378	8.8	25
SAS Super 180	180	401	2.1	40
Millipore Air Tester	140	1000	2.3	Plate supplied by manufacturer, ∼ 20 mL
RCS High Flow	100	N/A	1.2	Agar strip supplied by manufacturer

FIG. 1 Relative performance of portable impactors as a function of sampling time, t _S , when sampling bacteria indoors. The data represent averages and standard deviations from nine repeats.

FIG. 2 Relative performance of portable impactors as a function of sampling time, t _S , when sampling fungi indoors. The data represent averages and standard deviations from nine repeats.

FIG. 3 Relative performance of portable impactors as a function of sampling time, t _S , when sampling bacteria outdoors. The test samplers sampled outdoor air for t _COLL = 2 min and then sampled particle-free air for t _S −t _COLL , where t _S = 2, 5, 10, and 30 min. The data represent averages and standard deviations from nine repeats.

FIG. 4 Relative performance of portable impactors as a function of sampling time, t _S , when sampling fungi outdoors. The test samplers sampled outdoor air for t _COLL = 2 min and then sampled particle-free air for t _S −t _COLL , where t _S = 2, 5, 10, and 30 min. The data represent averages and standard deviations from nine repeats.

FIG. 5 Relative performance of portable impactors as a function of sampling time, t _S , when sampling bacteria outdoors. The test samplers sampled particle-free air for t _S − 2 min (t _S = 2, 5, 10, and 30 min) and then sampled outdoor air for t _COLL = 2 min. The data represent averages and standard deviations from nine repeats.

FIG. 6 Relative performance of portable impactors as a function of sampling time, t _S , when sampling fungi outdoors. The test samplers sampled particle-free air for t _S − 2 min (t _S = 2, 5, 10, and 30 min) and then sampled outdoor air for t _COLL = 2 min. The data represent averages and standard deviations from nine repeats.