NFPA 24 TEST KEY CONCEPTS AND
REVISION NOTES
◉ What is a hydrant isolation valve?
Answer: A valve that allows a hydrant to be isolated for service or
repair.
◉ What is hydrant drainage?
Answer: Drainage provisions for the hydrant barrel where
permitted and appropriate.
◉ What does FDC stand for?
Answer: Fire Department Connection; allows fire department
pumping into a water-based fire protection system.
◉ What is a backflow preventer?
Answer: An assembly that prevents reverse flow into the
supplying water system and can cause pressure loss.
◉ What is a check valve?
Answer: Permits flow in one direction and prevents reverse flow.
◉ What is a water supply in this context?
Answer: The source of water serving the private fire service main.
, ◉ What is bedding?
Answer: Suitable material/preparation supporting and protecting
underground pipe.
◉ What is backfill?
Answer: Material placed around and above underground piping
after installation.
◉ What is suitable backfill?
Answer: Material that supports and protects pipe without
damaging point loads, corrosion, or harmful settlement.
◉ What is unsuitable backfill?
Answer: Frozen earth, refuse, corrosive material, ashes, cinders,
organic matter, or other damaging material.
◉ What is a soft trench bottom?
Answer: Provide suitable bedding or another means of adequate
pipe support.
◉ What should be checked during pipe inspection before
installation?
Answer: Check pipe and fittings for cracks, damage, defects, and
contamination.
REVISION NOTES
◉ What is a hydrant isolation valve?
Answer: A valve that allows a hydrant to be isolated for service or
repair.
◉ What is hydrant drainage?
Answer: Drainage provisions for the hydrant barrel where
permitted and appropriate.
◉ What does FDC stand for?
Answer: Fire Department Connection; allows fire department
pumping into a water-based fire protection system.
◉ What is a backflow preventer?
Answer: An assembly that prevents reverse flow into the
supplying water system and can cause pressure loss.
◉ What is a check valve?
Answer: Permits flow in one direction and prevents reverse flow.
◉ What is a water supply in this context?
Answer: The source of water serving the private fire service main.
, ◉ What is bedding?
Answer: Suitable material/preparation supporting and protecting
underground pipe.
◉ What is backfill?
Answer: Material placed around and above underground piping
after installation.
◉ What is suitable backfill?
Answer: Material that supports and protects pipe without
damaging point loads, corrosion, or harmful settlement.
◉ What is unsuitable backfill?
Answer: Frozen earth, refuse, corrosive material, ashes, cinders,
organic matter, or other damaging material.
◉ What is a soft trench bottom?
Answer: Provide suitable bedding or another means of adequate
pipe support.
◉ What should be checked during pipe inspection before
installation?
Answer: Check pipe and fittings for cracks, damage, defects, and
contamination.
