NHIE/TREC Plumbing Questions with Detailed Verified Answers

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NHIE/TREC Plumbing Questions with
Detailed Verified Answers


Question: 1. A copper - to - steel connection undergoes a / an ?
a . Chemical reaction
b . Electrolytic reaction
c . Nuclear reaction
d . Thermal reaction


Ans: b . Electrolytic reaction


Question: 2. What causes water hammer ?
a . Loose pipes
b . Instantaneously closing valves
C. Hydrostatic shock
d . All of the above


Ans: d . All of the above


Question: 3. Name three common locations of cross connections in a
plumbing system .
a . Bidet , garden hose , and boiler connection
b . Toilet , sink , and bidet
c . Garden hose , laundry tubs , toilet d . Boiler connection , toilet , and lawn
sprinklers

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Ans: a . Bidet , garden hose , and boiler connection


Question: 4. Name two locations to install a check valve in a house with
combination sewers to reduce the risk of backup into the basement
a . Floor drains and main drain line
b . Basement sink and toilets
c . Hose bibs and pool self - fill mechanisms
d . None of the above


Ans: a . Floor drains and main drain line


Question: 5. The recommended slope for waste plumbing is typically ?
a . ¼ inch per foot
b . ½ inch per foot
c .3/4inch per foot
d . 1 inch per foot trap


Ans: a . ¼ inch per foot


Question: 6. What type of trap is no longer used in residential construction ?
a . S - trap
b . P - trap
c . Q - trappers
d . V - trap


Ans: a . S - trap


Question: 7. Describe the function of a trap primer .