Sample Laboratory Proficiency Exam Questions for Facility Operators
1. Determine the Total suspended solids from the following:
Weight of crucible 27.82l6 gr
Weight of crucible plus dry solids 28.0003 gr
Weight of crucible plus ash 27.9673 gr
Weight of crucible plus wet solids 32.6l05 gr
Sample Volume 50 ml
a) 660 mg/L
b) 2394 mg/L
c) 2914 mg/L
d) 3570 mg/L
2. If one of the samples for which you must determine B.O.D. is a chlorinated effluent, you must remember to add ___________ to the dilution water.
b) the four "buffers"
3. All of the following pieces of laboratory equipment are required to determine total suspended solids.
a) Balance, muffle furnace, oven
b) Oven, desiccator, muffle furnace
c) Balance, oven, desiccator
d) Desiccator, muffle furnace, balance
4. Fecal coliform counts should be reported as monthly
a) Arithmetic means
b) Geological averages
c) Geometric means
Hopefully you scored well. The answers are D, C, C, and C.