BACKFLOW PREVENTION EXAM PREP
STUDY GUIDE QUESTIONS ANSWERS
COMPLETE SOLUTION BUNDLE
●● What are the two main causes of backflow?
Answer: Back-pressure and back-siphonage.
●● What is back-pressure?
Answer: Back-pressure is caused when downstream pressure becomes
greater than upstream pressure.
●● Give two possible causes of back-pressure.
Answer: Pump operation and hot water expansion.
●● What can happen if upstream pressure is unexpectedly lost?
Answer: It can contribute to back-pressure and cause reverse flow.
●● What is back-siphonage?
Answer: Back-siphonage is caused by negative pressure creating a
vacuum effect in the mains supply.
, ●● What happens if a submerged outlet is flowing when mains pressure
is lost?
Answer: Contaminated water can be drawn back into the wholesome
supply.
●● Which cause of backflow is associated with a vacuum in the mains?
Answer: Back-siphonage.
●● What is the purpose of backflow prevention?
Answer: To protect the wholesome water supply from contamination.
●● What are the two main types of backflow prevention arrangements?
Answer: Non-mechanical and mechanical.
●● Which type of backflow prevention usually gives the highest level of
protection?
Answer: Non-mechanical air gap protection.
●● What is meant by whole-site protection?
Answer: Protection installed at the point of entry to keep the
undertaker's main free from contamination risk.
●● Where is whole-site protection generally required?
STUDY GUIDE QUESTIONS ANSWERS
COMPLETE SOLUTION BUNDLE
●● What are the two main causes of backflow?
Answer: Back-pressure and back-siphonage.
●● What is back-pressure?
Answer: Back-pressure is caused when downstream pressure becomes
greater than upstream pressure.
●● Give two possible causes of back-pressure.
Answer: Pump operation and hot water expansion.
●● What can happen if upstream pressure is unexpectedly lost?
Answer: It can contribute to back-pressure and cause reverse flow.
●● What is back-siphonage?
Answer: Back-siphonage is caused by negative pressure creating a
vacuum effect in the mains supply.
, ●● What happens if a submerged outlet is flowing when mains pressure
is lost?
Answer: Contaminated water can be drawn back into the wholesome
supply.
●● Which cause of backflow is associated with a vacuum in the mains?
Answer: Back-siphonage.
●● What is the purpose of backflow prevention?
Answer: To protect the wholesome water supply from contamination.
●● What are the two main types of backflow prevention arrangements?
Answer: Non-mechanical and mechanical.
●● Which type of backflow prevention usually gives the highest level of
protection?
Answer: Non-mechanical air gap protection.
●● What is meant by whole-site protection?
Answer: Protection installed at the point of entry to keep the
undertaker's main free from contamination risk.
●● Where is whole-site protection generally required?