What is backflow in a plumbing system?
Correct Answer
B) Undesired reversal of flow that can contaminate the potable water supply
Backflow is an undesired reversal of flow that can draw or push contaminants into potable water. Other choices describe drainage, HVAC air movement, or pressure shock.
Why This Is the Correct Answer
Backflow is an undesired reversal of flow that can draw or push contaminants into potable water. Other choices describe drainage, HVAC air movement, or pressure shock.
More NASCLA Questions
Bid instructions require bid security with each sealed bid. Which purpose should the estimator associate with that requirement?
Two addenda revise the drawings before bid day. What must a responsive bidder normally do with those addenda?
An asphalt-shingle roof has a slope of 3:12. Under the IBC low-slope asphalt-shingle provisions, what underlayment arrangement is required?
A rooftop unit schedule lists capacity in tons of cooling. In HVAC estimating, one ton of cooling equals what heat-transfer rate?
The bid form asks for a base bid and three alternates. How should the contractor submit alternate pricing?
A specification includes a $40,000 hardware allowance because final selections are pending. How is the allowance treated in the bid?
The earthwork section requires unit prices for unsuitable-soil removal. What is the contract-administration use of those unit prices?
Before the first progress payment, the owner requests a schedule of values. What is its main contract-payment function?
A signed change order is issued for added lobby millwork. Which contract effect should it state?
On the finish plan, locate room R358; then use the finish schedule. What remarks is listed?
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