In the Laboratory edited by
Cost-Effective Teacher
Harold H. Harris University of Missouri—St. Louis St. Louis, MO 63121
Sink Inserts for Flood Prevention Fraser F. Fleming,* Daniel J. Bodnar, and David L. Hardesty Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282-1530; *
[email protected] Organic chemistry experiments typically require large volumes of water for water aspirators and condenser cooling. The use of large volumes of water creates the potential for flooding that has stimulated the development of several devices for minimizing water consumption (1) and for shutting off the water supply with remotely operated solenoids (2). The opportunity for water overflow is exacerbated in labs where one water trough services multiple faucets, particularly when being used at full capacity, since even small items can sufficiently constrict the outlet flow with high water volumes to cause flooding. In an effort to overcome the notorious “paper towel syndrome” we have devised a simple, cost-effective insert that effectively prevents flooding in lab sinks. The insert is essentially a plastic pipe, 0.5-cm wall diameter, with vertical slots, 0.5-cm wide, strategically cut in the side to prevent small lab items from entering the drain (Figure 1). The pipe diameter is slightly larger than the inside diameter of the drain so that a slight compression ensures a snug fit in the sink drain with
the usual wire sink guard removed. Approximately 1 cm of the guard is pushed into the drain with the remaining portion exposed above the drain. Positioning the first slots in the end allows the insert to be compressed while leaving a sufficient opening for continuous water flow to the drain, preventing water from pooling in the base of the sink. The insert has provided uniformly excellent results. No flooding has yet been observed in any of the labs having the inserts and attempts to cause flooding with multiple paper towels have been fruitless (Figure 2). Typically high water flow causes paper towels to float on the surface around the insert with the water continuing to efficiently exit through the lower vertical slots. The insert is remarkably efficient, inexpensive, and dramatically diminishes the risk of flooding. Literature Cited 1. Fleming, F. F.; Iyer, P. S. J. Chem. Educ. 2001, 78, 946. 2. Conlon, D. R. J. Chem. Educ. 1966, 43, A589.
3.5 cm
2.5 cm
4.5 cm
6.0 cm
3.5 cm
Figure 2. Sink insert in use; a paper towel is surrounding the insert but does not prevent water from draining.
Figure 1. Sink insert.
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Journal of Chemical Education
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Vol. 81 No. 9 September 2004
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www.JCE.DivCHED.org
