Questions and Answers 100% Verified
The only absolutely reliable method of backflow prevention is the use of - ANSWER-
Air Gap
The bubbles formed in a positive multiple tube fermentation test are - ANSWER-
Carbon Dioxide
The maximum rate of withdrawal of gas from a 150lb chlorine cylinder in 24-hours is
- ANSWER-40 lbs
If you encounter a liquid chlorine leak in a one tone container, what action should
you take first, to reduce the severity of the leak? - ANSWER-Rotate the container to
place the leak at the top
The most commonly used water disinfectant in the United States is - ANSWER-
Chlorine
When collecting a distribution system sample, the water should be allowed to run for
a period of time prior to sample collection. How long - ANSWER-As long as
necessary to permit cleaning of service line
Sample bottles wich are furnished by a certified laboratory for collection of
bacteriological samples - ANSWER-Are ready to use
The difference between water pressure upstream and downstream of a pump when
it is not in operations is know as the - ANSWER-Total static head
A device that automatically shuts off flow in an elevated storage tank when the water
level in the tank reache a preset level is termed a - ANSWER-Altitude valve
In an occupied trench requiring personal egress what is the maximum allowable
distance between a worker and an exit letter - ANSWER-25 feet
A water bearing formation in the soil is referred to as - ANSWER-An aquifer
The distance between the static water level and the pumping water level is termed
the - ANSWER-Drawdown
To prevent the entry of surface contamination into a well is the purpose of -
ANSWER-Sanitary seal