DEMAND FLOW RATE INCREASE
Number of Inlets
41 and above
The demand usage factor is normally 100 percent.
Verify the specific
usage factor with the User and the Design Agent.
Separator Tank. The separator/collector tanks shall be
sized according to Table 9-11.
SEPARATOR TANK SIZING
Minimum Size L (Gal)
Number of DTR's
31 and above
10.5 (2.75) per DTR
An alternative separator tank-sizing factor is 10.45 liters (2.75
gallons) per DTR. The use of multiple tanks can be considered for the
lower number of DTR's if continuous operation is necessary. Tank
drainage piping shall slope from the tank discharge point down to the
discharge point at the floor drain or standpipe receptor.
Equipment Location. The DLV equipment shall be located on or
below the DTR floor level. The separator tank location shall be near the
pump at the same level or directly above or below whenever feasible.
When space constraints are unavoidable, after coordination with the
Design Agent and using Service, or other circumstances dictate, vacuum
pumps may be located above and remote from the separator tank. The pipe
shall then be sized to maintain system pressure loss within the maximum
limit. The tank drain valve discharge shall be a minimum 150 millimeter
(0.5 foot) above the floor to accommodate the pipe slope, drain line turn
down and the indirect connection air gap to the sanitary drainage system
receptor. The sanitary waste centerline of pipe shall be a minimum 0.34
meter (1 foot) below the floor to accommodate the floor drain trap. The
equipment room shall be located as near the DTR's as possible to minimize
distribution piping bends and pipe length. Equipment placement in the
mechanical room shall be arranged to provide the most direct connection
to the distribution piping, the sanitary waste line, and the exhaust
discharge point, in that order.
Piping Distribution. The piping run from the dental utility
center, located on or recessed into the floor, should continuously slope
back to the vacuum source equipment with limited rise, to facilitate
transportation of fluids and particulate. Minimum required slope is 0.65
centimeter per 3.0 meter (1/4 inch per 10 feet). Vacuum shall be
increased from the level specified in 188.8.131.52 at the rate of 1 in-Hg for
every 1.1 foot of rise. Distribution system piping encased in the slab
or buried below the slab shall be a minimum 50 millimeter (2 inch) in