Why does a plumbing fixture trap need a water seal?
Correct Answer
C) To block sewer gas from entering the occupied space
The trap seal blocks sewer gas from passing through the fixture drain into the occupied space. Other choices are unrelated to trap function.
Why This Is the Correct Answer
The trap seal blocks sewer gas from passing through the fixture drain into the occupied space. Other choices are unrelated to trap function.
Why the Other Options Are Wrong
Option A: Use trap seal to increase hot-water temperature
Choice A gives To increase hot-water temperature. Its specific error: it answers the Trap seal prompt with the wrong practical move.
Option B: Use trap seal to support the fixture weight
Choice B (To support the fixture weight) is rejected because it leaves out the controlling Trap seal result: To block sewer gas from entering the occupied space.
Option D: Use trap seal to reduce duct noise
The trap in D is To reduce duct noise. That selection is wrong because the option does not produce the required Trap seal outcome, To block sewer gas from entering the occupied space.
Memory Technique
Make trap seal a purpose cue; if the choice changes the purpose, it cannot be To block sewer gas from entering the occupied space.
Reference Hint
Open Pipe and Excavation Contracting, 2011; use the index entry or section for "Fixture trap function" to confirm that The trap seal blocks sewer gas from passing through the fixture drain into the occupied space.
More NASCLA Questions
Bid instructions require bid security with each sealed bid. Which purpose should the estimator associate with that requirement?
A wood deck surface has 320 sf of coverage. Boards have a 5-1/2 in. actual face width, and the order includes an 8 percent cutting allowance. What linear footage is closest?
Using the dimensions shown for the stabilized construction entrance, what is the plan area?
A reroof area requires 14,720 sf of rigid insulation. Boards are 4 ft by 8 ft, and the order includes 5 percent waste. How many boards are needed?
Two addenda revise the drawings before bid day. What must a responsive bidder normally do with those addenda?
A utility trench is 180 ft long, 3 ft wide, and 7 ft deep with vertical sides inside a trench shield. What excavation volume is required?
A 120 ft long Type C trench is cut with a 4 ft bottom width and a 6 ft depth. If side slopes are 1-1/2 horizontal to 1 vertical, what excavation volume is closest?
A storm pipe run needs 240 ft of bedding, 4 ft wide and 6 in. thick. Including a 10 percent ordering allowance, how many cubic yards of bedding aggregate are needed?
A mass excavation produces 1,180 loose cubic yards of material for off-site disposal. End-dump trucks can haul 18 loose cubic yards per trip. What truck count is required?
An asphalt-shingle roof has a slope of 3:12. Under the IBC low-slope asphalt-shingle provisions, what underlayment arrangement is required?
People Also Study
Business & Financial Management
120 questions · 70% to pass
Contract Administration
60 questions · 70% to pass
Project Management
60 questions · 70% to pass