77 Ill. Adm. Code 890.660
Urinals
Section 890
Section 890.660 Urinals
a) Automatic Flushing Tank.
1) Flushing tanks shall be used for washout urinals only. Tanks
flushing more than one (1) urinal shall be automatic, shall provide a
sufficient volume of water to flush all urinals simultaneously, and shall flush
at least four (4) times per hour. One automatic flushing tank may serve no more
than three (3) washout urinals.
2) Float Valves. Float valves or ball cocks, if provided for
flushing tanks, shall be of the anti-siphon type and of sufficient capacity to
refill the trap.
b) Urinal Flush Valves. No valve shall be used to flush more
than one (1) blow-out, siphon-jet or pedestal urinal. One (1) properly sized
automatic flush valve may serve more than one (1), but not more than a battery
of three (3) washout urinals, and shall flush at least four (4) times per hour.
The water supply line to each urinal flush valve shall be as required by the
manufacturer, but not less than three-fourths (3/4) inch. Protection against
backflow shall be provided by an approved vacuum breaker. (See Sections
890.1130(a), (b), (c) and 890.1140.)
c) Trough urinals are prohibited.