A fixture unit shall mean a unit of measure representing the sewage load-producing effects on the sewer system of different kinds of plumbing fixtures based upon the trap size required (Table 1 of this section) or the rated discharge capacity expressed in gallons per minute (Table 2 of this section).
(a)
Table 1:
Type of Fixture | Trap Size | Fixture Units |
|---|---|---|
Bath Tub | 1-1/2" | 2 |
Dental Cuspidor | 1-1/2" | 1 |
Drinking Fountain | 1-1/4" | 1 |
Dump Stations, Recreational Vehicle | 4" | 8 |
Floor Drain | 2" | 2 |
Floor Drain | 3" | 3 |
Floor Drain | 4" | 4 |
Interceptor: Grease, Oil and Solids (Grease Trap) | 2" | 3 |
Interceptor: Sand, Auto Wash (sand trap) | 3" | 6 |
Interceptor: Sand, Auto Wash (sand trap) | 4" | 8 |
Laundry Tub or Clothes Washer (Residential) | 1-1/2" | 2 |
Laundry Tub or Clothes Washer (Self-service Laundry) | 1-1/2" (per unit) | 2 (per unit) |
Receptor (Floor sink, refrigerators, coffee urns, water stations) | 1-1/2" | 1 |
Receptor (Commercial sinks, dishwashers, air washers) | 2" | 3 |
Shower (Single stall) | 2" | 2 |
Shower (Gang) | 2" | 2 (per head) |
Sink (Residential Bar) | 1-1/2" | 1 |
Sink (Commercial Bar) | 1-1/2" | 2 |
Sink (Industrial, commercial, schools, including dishwashers, wash-up locations and wash fountains) | 1-1/2" | 3 |
Sink (Flushing rim clinic) | 3" | 6 |
Sink or Dishwasher (Residential) | 1-1/2" | 2 |
Sink (Service) | 2" | 3 |
Trailer Park Trap | 3" | 6 (per trailer) |
Urinal | 1-1/2" | 2 |
Urinal Trough | 1-1/2" | 2 (per 2 feet) |
Wash Basin (Residential lavatory) | 1-1/4" | 1 |
Wash Basin (Commercial lavatory) | 1-1/4" | 2 |
Water Closet (Residential) | 3" | 6 |
Water Closet (Commercial) | 3" | 8 |
(1)
Trap size is measured in inches in diameter.
(2)
The trap size and fixture unit rating of each waste receptor and interceptor is only a minimum and shall be based on the total rated discharge capacity of all fixtures, equipment or appliances discharging therein.
(3)
A receptor is an approved plumbing fixture or device of such material, shape, and capacity as to adequately receive the discharge from indirect waste pipes, so constructed and located as to be readily cleaned.
(b)
If a particular type of fixture is not reflected in Table 1, or a particular trap size is larger than that reflected in Table 1; or greater loading is evident, the fixture unit(s) shall be based upon the rated discharge capacity, expressed in gallons per minute, reflected in Table 2, shown below.
(1)
Table 2.
Rated Discharge Capacity (measured in gallons per minute) | Trap Size | Fixture Units |
|---|---|---|
0-7-1/2 | 1-1/4" | 1 |
8-15 | 1-1/2" | 3 |
16-30 | 2" | 4 |
31-50 | 3" | 6 |
Over 50 | --- | Determined by Director |
(1018-CS, Added, 02/12/2004, Renumbered to 6-4-1401)