The typical strength range of calcium hypochlorite
What is 65%?
100
This gas is detected by the smell of rotten eggs. It will cause acute poisoning and paralyze the respiratory system at 0.07%-0.1 % concentrations.
What is hydrogen sulfide?
100
There are this many gallons in 2,167 cubic feet.
What is 16,209 gal
100
Tube settlers are used in sedimentation to do this.
What is increase surface area or reduce the detention time needed?
100
The media in a dual media filter shall have a depth of no less than_________ inches.
What is 30 inches?
200
The two most important factors in effective chlorination.
What are concentration and contact time?
200
The safety procedure that requires that an energy source be turned off and locked, and that information describing why a system is shut down is displayed on a tag is called _____.
What is lock out/tag out ?
200
Convert 8.60 MGD into cubic feet per second.
What is 13.3 cfs ?
200
The primary reason for the use of a dry barrel fire hydrant.
What is to prevent freezing?
200
The secondary MCL for manganese in drinking water?
What is 0.05 mg/L?
300
The major disadvantage of using UV for disinfection in water treatment.
What is the lack of a residual?
300
When using ammonia to test for the presence of a chlorine leak, if a leak is present the reaction will create this.
What is white smoke?
300
The specific gravity for a solution that weighs 10.27 lb/gal.
What is 1.23?
300
The basic unit of electrical power is which of the following (the ohm, the watt, or the volt).
What is the watt?
300
Records of bacteriological analysis must be kept for this length of time.
What is 5 years?
400
The primary purpose of adding fluoride to drinking water.
What is to prevent dental cavities in children?
400
The location for exhaust fans in a chlorine room.
What is near the floor?
400
If the chlorine dose is 4.25 mg/L and the chlorine residual is 1.20 mg/L, This is the chlorine demand in mg/L.
What is 3.05 mg/L?
400
Which of the following valve types is the most suitable for a throttling application (butterfly valve, check valve, gate valve).
What is a butterfly valve?
400
A Tier 1 violation is a situation with the potential to have adverse effects on human health as a result of short term exposure. The length of time you have to provide Tier 1 public notice is __.
What is ASAP but within 24 hours?
500
The point at which the chlorine dose has met the demand and additional chlorine will result in a free residual.
What is the breakpoint?
500
The odor detection lomit for chlorine gas.
What is 0.3 ppm?
500
A channel is 7 ft wide has water flowing to a depth of 3 ft and a velocity of 2.8 fps. The flow through the channel in cfs is ___.
What is 59 cfs.
500
A mechanical device consisting of 2 independently operating, spring loaded check valves with a reduced pressure zone between checks designed to protect against both backpressure and backsipohnage.
What is a reduced pressure backflow preventer (RPBP)?
500
A water system has been notified that they have a positive total coliform sample. The system must take a set of repeat samples within ______ hours.