Pipefitting and Plumbing Flashcards
6 cards from real Other Skilled Trades practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Pipefitting and Plumbing flashcards as text
What is the purpose of an air gap in a plumbing installation?
Answer: To provide a physical break preventing backflow from contaminating the potable water supply
An air gap is a physical space between the water supply outlet and the flood rim of a fixture, ensuring backflow of contaminated water into the potable supply is impossible.
What does CPVC stand for and what distinguishes it from PVC in plumbing?
Answer: Chlorinated Polyvinyl Chloride — rated for hot water up to 200°F vs PVC's 140°F limit
CPVC (Chlorinated Polyvinyl Chloride) is further chlorinated, giving it a higher temperature rating (up to 200°F) compared to standard PVC, making it suitable for hot water supply lines.
In pipefitting, what is the difference between a 'long radius' and 'short radius' elbow?
Answer: Long radius has a centerline radius of 1.5x the pipe diameter; short radius has 1x the pipe diameter
A long radius elbow has a centerline bend radius of 1.5 times the nominal pipe diameter, causing less pressure drop and turbulence than a short radius elbow with a 1x diameter radius.
What is the required burial depth (cover) for water service lines in a frost-prone area of the northern US?
Answer: At or below the local frost depth
Water service lines must be buried below the local frost depth (which varies by region) to prevent the water in the line from freezing and potentially rupturing the pipe.
What is the maximum temperature rating for CPVC used in residential hot water supply lines per most US plumbing codes?
Answer: 200°F
CPVC is rated for continuous service at up to 200°F, which is why it is approved for hot water supply applications where standard PVC would fail.
Which fitting is required where a horizontal drain branch connects to a vertical stack in a DWV system?
Answer: A sanitary tee or wye fitting
Sanitary tee or wye fittings are required at horizontal-to-vertical drain connections because their swept design promotes flow in one direction and resists siphoning, unlike standard tees.