Illinois Administrative Code (Last Updated: February 21, 2024) |
TITLE77. PUBLIC HEALTH |
PART890. ILLINOIS PLUMBING CODE |
SUBPARTM. INSPECTIONS, TESTS, MAINTENANCE AND ADMINISTRATION |
Section890.APPENDIX A. Plumbing Materials, Equipment, Use Restrictions and Applicable Standards |
§890.TABLE O. Water Supply Fixture Units (WSFU) for a Supply System with Flushometer Water Closets
-
WSFU
Demand (GPM)
Pipe Size (Inches)
Pressure Loss (PSI/100'
of Pipe)
Velocity (Ft./Sec.)
Meter Size (Inches)
10
27
1¼"
8.3
6.8
¾"
12
28.6
1¼"
9.2
7.2
¾"
14
30.2
1¼"
10
7.9
¾"
16
31.8
1¼"
11
8.0
¾"
20
35
1½"
6.0
6.4
¾"
25
38
1½"
7.0
6.9
1"
30
41
1½"
8.0
7.4
1"
35
43.8
1½"
8.8
8.0
1"
40
46.5
2"
2.5
4.7
1"
45
49
2"
2.7
5.1
1"
50
51.5
2"
2.9
5.4
1½"
60
55
2"
3.4
5.8
1½"
70
58.5
2"
3.7
6.0
1½"
80
62
2"
4.0
6.2
1½"
90
64.8
2"
4.6
6.5
1½"
100
67.5
2"
5.0
6.8
1½"
120
72.5
2"
5.6
7.2
2"
140
77.5
2"
6.3
8.0
2"
160
82.5
2½"
2.7
5.7
2"
180
87
2½"
3.0
6.1
2"
200
91.5
2½"
3.4
6.4
2"
225
97
2½"
3.7
6.8
2"
250
101
2½"
4.0
7.1
3"
275
106
2½"
4.2
7.3
3"
300
110
2½"
4.6
7.6
3"
350
119
3"
2.1
5.5
3"
400
126
3"
2.3
5.9
3"
450
138
3"
2.7
6.3
3"
500
145
3"
3.0
6.8
3"
600
160
3"
3.6
7.4
4"
750
178
4"
1.1
4.7
4"
1000
208
4"
1.5
5.6
4"
1250
240
4"
1.9
6.4
4"
1500
267
4"
2.3
7.0
4"
1750
294
4"
2.8
7.8
4"
2000
321
6"
0.4
3.7
6"
Agency Notes:
Where a unit of local government or the community public water supply does not require separate water service lines for irrigation or similar systems that are likely to impose continuous demands (e.g., lawn sprinkler or air conditioning systems), the following rule applies: estimate the continuous demand (in gallons per minute) for outlets/systems separately from the intermittent demand from the above fixtures, and add this amount to the demand of the fixtures (in gallons per minute).
Meter and meter yoke sizes shown in this table shall apply only to those jurisdictions or governmental units where local ordinances or community public water supply requirements do not prescribe specific sizes of meters or meter yokes. Where local ordinances or community public water supply requirements cover such sizing, those requirements shall be followed.
(Source: Amended at 38 Ill. Reg. 9940, effective April 24, 2014)