The only absolutely reliable method of backflow prevention is the use of correct answers Air
Gap
The bubbles formed in a positive multiple tube fermentation test are correct answers Carbon
Dioxide
The maximum rate of withdrawal of gas from a 150lb chlorine cylinder in 24-hours is correct
answers 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? correct answers Rotate the container to place the leak at the
top
The most commonly used water disinfectant in the United States is correct answers 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 correct answers As long as necessary to permit
cleaning of service line
Sample bottles wich are furnished by a certified laboratory for collection of bacteriological
samples correct answers 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 correct answers 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 correct answers Altitude valve
, In an occupied trench requiring personal egress what is the maximum allowable distance
between a worker and an exit letter correct answers 25 feet
A water bearing formation in the soil is referred to as correct answers An aquifer
The distance between the static water level and the pumping water level is termed the correct
answers Drawdown
To prevent the entry of surface contamination into a well is the purpose of correct answers
Sanitary seal
The presence of coliform bacteria in a distribution system correct answers Indicates that
pathogenic organisms may be present also
The most common valve type in water distribution system is the correct answers Gate valve
A Venturi is a device used to correct answers Measure water flow
Backspin is occurring after well shut down this indicates correct answers A faulty check valve
A ph reading of 6.0 units indicates the water sample is correct answers Slightly acidic
Chlorine gas correct answers Is heavier than air
The change in what're demand during the course of a day is called correct answers Diurnal
variation
Catholic protection is a system used for correct answers Metallic corrosion inhibition