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                                                                           4.5 Demand and Drainage Loads of Buildings  141
                                         Table 4.15  Fixture Rates
                                                                                                            3
                                                                                    Rates of Supply and Discharge, ft /min
                                         Type of Fixture and Supply (1)             Private             Public and
                                         and Discharge (2)                          Buildings         Office Buildings
                                         Wash basin, faucet—(1) and (2)                1                   2
                                         Water closet, (2) only                        6                    8
                                           flush tank, (1) only                        3                   5
                                           flush valve, (1) only                       6                   10
                                         Urinal
                                           (stall or wall), flush tank (1) only       . . .                 3
                                           (stall or wall), flush valve               . . .                 5
                                           (pedestal), flush valve                    . . .                10
                                         Bathtub or shower, faucet or mixing valve     2                   4
                                         Bathroom group (2) only                       8                  . . .
                                           flush tank for closet, (1) only             6                  . . .
                                           flush valve for closet, (1) only            8                  . . .
                                           separate shower head, (1) only              2                  . . .
                                           separate shower stall, (2) only            10                  . . .
                                         Kitchen sink, faucet 2                        2                   4
                                         Laundry trays (1 to 3), faucet                3                  . . .
                                         Combination fixture, faucet                   3                  . . .
                                         Service sink, faucet (hotel or restaurant)   . . .                 3
                                         Sill cock                                     2 3                 2 3

                                                                              3
                                                        3
                                         Conversion factor: 1 ft /min   28.32 L/min   0.02832 m /min.
                                             3. Fixtures supplied with both hot and cold water exert reduced demands on main
                                                hot-water and cold-water branches (not fixture branches). An allowance of three-
                                                fourths of the demand shown in Table 4.15 for individual fixtures is suggested.



                                                                                      3
                    Figure 4.5 Demand Load on                       Total fixture demand, ft /min
                    Water Piping. Conversion        300 280 260  240  220  200 180 160 140 120 100 80  60  40  20  0
                           3
                    factor: 1 ft /min             400                                                    100
                                                 Probable demand load on water piping, gpm  200  Systems with flush valves (primarily)  60 Probable demand load on piping, gpm
                                    3
                    7.48 gpm   0.0283 m /min.
                    1 gpm   3.785 L/min.          300                                 Bottom and left scales  80




                                                                                     Top and right scales
                                                                                                         40
                                                                               Top and right scales
                                                  100




                                                                                                         0
                                                        200  400  600  800  1,000  1,200  1,400  1,600  1,800  2,000  2,200  2,400  2,600  2,800  3,000
                                                    0            Systems with flush tanks (primarily)    20
                                                                                           3
                                                               Total fixture demand, fixture units, ft /min
   174   175   176   177   178   179   180   181   182   183   184