September 2007, Vol. 19, No.9
Test Your Knowledge of Laboratry Practices
Multiple Choice Questions:
In a wastewater setting, the results of a biochemical oxygen demand test indicate which of the following factors?
A. A measure of the ability of the wastewater to neutralize acid.
B. A relative measure of the amount of food material available to the biological system, degree of stabilization of the wastewater, and prospective effect of the effluent on the receiving water.
C. A measure of how much oxygen a sample will consume.
D. A measure of the ability of an aqueous solution to carry an electrical current.
Which of the following factors must be added together to find total solids?
A. Settleable and dissolved solids.
B. Settleable and nonsettleable solids.
C. Dissolved solids and nonsettleable solids.
D. Settleable, nonsettleable, and dissolved solids.
Which of the following actions is NOT needed to prevent biological fouling or alteration of a sample when using an autosampler?
A. Clean the sampling equipment and containers before the sampling event.
B. Analyze blanks on automatic sampling equipment to determine whether or not the equipment is causing contamination.
C. Reset the sampling equipment power supply before beginning sampling.
D. Ensure that sample collection bottles have been acid-washed (when appropriate) and rinsed with distilled water and dried before sampling.
After calculating what volume of sample will be needed to perform the required tests, what volume of sample water should be collected?
A. A volume equal to the amount needed for the tests.
B. A volume equal to the amount needed for the tests, plus an additional 50%.
C. A volume equal to the amount needed for the tests, plus an additional 100%.
D. A volume equal to the amount needed for the tests, plus an additional 100%.
What is the maximum holding time for a properly preserved COD sample?
A. 5 days.
B. 13 days
C. 23 days.
D. 28 days.
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Questions were developed by Steve Spicer and reviewed by the Association of Boards of Certification (Ames, Iowa) Validation and Examination Committee.
Water Environment Federation (2006). Automation of Wastewater Treatment Facilities, Third edition; Manual of Practice No. 21. Alexandria, Va.: Water Environment Federation.
Water Environment Federation (1996). Operation of Municipal Wastewater Treatment Plants; Manual of Practice No. 11, Fifth Ed. Alexandria, Va.: Water Environment Federation.