Plumbing Fixtures, Faucets, and Fixture Fittings
Approved fixtures and installation rules
Fixtures must be of an approved, listed type with smooth, nonabsorbent surfaces, installed level, securely fastened, and accessible for cleaning. Water closets, urinals, lavatories, sinks, showers, and drinking fountains each carry efficiency limits set by federal and state law; the adopted Arkansas code may be stricter than the federal maximum, so verify before answering an efficiency question. Every fixture that discharges to the drainage system needs a trap - either integral to the fixture or installed immediately below it - and the fixture outlet to the trap must be short (commonly not over 24 inches developed length).
Fittings and connections
Slip-joint tubular fittings are used above the floor for lavatory and sink waste; they must be accessible. Escutcheons close wall and floor penetrations. Floor drains need trap primers or another means of maintaining the trap seal. Drinking fountains, coffee makers, and hose connections need backflow protection.
Traps the exam sets
- Confusing the fixture-outlet length limit with the trap-arm length limit.
- Forgetting that a fixture with an integral trap still needs a vented drain.
- Shower and tub-shower valves must be pressure-balancing or thermostatic, with a scald limit at the outlet.
- Accessible fixtures require knee and toe clearance and a maximum rim height.
- Setting a water closet on a damaged flange or reusing a worn wax ring.
Rule of thumb: if a fixture connects to the potable supply and can be submerged or connected to nonpotable equipment, assume it needs backflow protection until the code table proves otherwise.