Water Supply Systems Flashcards
6 cards from real 306A practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Water Supply Systems flashcards as text
What is the minimum burial depth for a water service pipe in most Canadian jurisdictions?
Answer: At or below the local frost depth
The water service pipe must be buried at or below the local frost depth to prevent freezing. In Canada, this depth varies significantly by region, from about 1.2 m in southern areas to over 2.4 m in northern regions.
What type of copper tubing is required for above-ground water distribution within a building?
Answer: Type L or Type M
Type L or Type M copper tubing is used for above-ground water distribution. Type L is more common due to its heavier wall thickness providing better durability, while Type M is acceptable for lower-pressure residential applications.
What is the main advantage of PEX tubing over copper for water supply distribution?
Answer: Resistance to freezing damage and flexibility for routing
PEX tubing is flexible, allowing it to bend around obstacles without fittings, and it can expand slightly without bursting if water freezes inside, making it more resistant to freeze damage than rigid copper.
When connecting dissimilar metals in a water supply system (e.g., copper to steel), what must be used to prevent galvanic corrosion?
Answer: A dielectric union or dielectric fitting
A dielectric union separates the two dissimilar metals with an insulating material to prevent galvanic corrosion, which occurs when different metals are in direct contact in the presence of an electrolyte (water).
What is the minimum hot water storage temperature required to prevent Legionella bacteria growth?
Answer: 60°C
Hot water must be stored at a minimum of 60°C (140°F) to kill Legionella bacteria, which thrive between 20°C and 45°C. A mixing valve then tempers the water to a safe delivery temperature.
What device is required on a water supply system to prevent municipal water from being contaminated by building plumbing?
Answer: Backflow prevention device at the service entrance
A backflow prevention device at the water service entrance prevents contaminated water from the building's plumbing system from flowing back into the municipal water supply, protecting public health.