An Inexpensive, Accurate Air Sampling Pump A recent note1 on ingenious uses of plastic pop bottles inspired us to develop a simple aspirator system that is versatile and w r n r a t e A K i n hnle i s drilled throoeh the center of the base of a 2-1 olastic bottle. A 0.25-ml disposable pipet tip is
.i #4
rubber stopper fitted with a short length of glass tubing. When the bottle is filled with water, the flaw ratecan be controlled over arange of 100-700 mllmin by suitably adjusting the Hoffman clamp. The volume of air sampled by this method is readily determined by measuring the volume of water collected. Sufficient vacuum is oroduced to null air easily through a fritted bubbler. Two bottles can be alternated as pump and receiver to conveniently handle the us&l10-20~1 sample klumes. This system is performing effectively in an institute-wide air sampling project being carried out by our chemistry and environmental science majors. Aronson, J.N., J. CHEM. EDUC.,56,476(1979) P a u l Friedman
P r s t t Institute Brooklyn, NY 11205
Volume 58
Number 2
February 1981
199
