Table 703.2

Question 1

Maximum Units
Drainage Piping
Vertical
Horizontal

Pipe size - 1 1/4

Answer 1

Vertical 1
Horizontal 1

Question 2

Maximum Units
Drainage Piping
Vertical
Horizontal

Pipe size - 1 1/2

Answer 2

Vertical: 2
Horizontal: 1

Question 3

Maximum Units
Drainage Piping
Vertical
Horizontal

Pipe size - 2

Answer 3

Vertical: 16
Horizontal: 8

Question 4

Maximum Units
Drainage Piping
Vertical
Horizontal

Pipe size - 3

Answer 4

Vertical: 48
Horizontal: 35

Question 5

Maximum Units
Drainage Piping
Vertical
Horizontal

Pipe size - 4

Answer 5

Vertical: 256
Horizontal: 216

Question 6

Maximum Length
Drainage Piping
Vertical (feet)
Horizontal (unlimited)

Pipe size - 1 1/4

Answer 6

45

Question 7

Maximum Length
Drainage Piping
Vertical (feet)
Horizontal (unlimited)

Pipe size - 1 1/2

Answer 7

65

Question 8

Maximum Length
Drainage Piping
Vertical (feet)
Horizontal (unlimited)

Pipe size - 2

Answer 8

85

Question 9

Maximum Length
Drainage Piping
Vertical (feet)
Horizontal (unlimited)

Pipe size - 3

Answer 9

212

Question 10

Maximum Length
Drainage Piping
Vertical (feet)
Horizontal (unlimited)

Pipe size - 4

Answer 10

300

Question 11

Vent Piping
Horizontal and Vertical
Maximum Units
Maximum Lengths (feet)

Pipe size - 1 1/4

Answer 11

Maximum Units: 1
Maximum Lengths: 45’

Question 12

Vent Piping
Horizontal and Vertical
Maximum Units
Maximum Lengths (feet)

Pipe size - 1 1/2

Answer 12

Maximum Units: 8
Maximum Lengths: 60’

Question 13

Vent Piping
Horizontal and Vertical
Maximum Units
Maximum Lengths (feet)

Pipe size - 2

Answer 13

Maximum Units: 24
Maximum Lengths: 120’

Question 14

Vent Piping
Horizontal and Vertical
Maximum Units
Maximum Lengths (feet)

Pipe size - 3

Answer 14

Maximum Units: 84
Maximum Lengths: 212’

Question 15

Vent Piping
Horizontal and Vertical
Maximum Units
Maximum Lengths (feet)

Pipe size - 4

Answer 15

Maximum Units: 256
Maximum Lengths: 300’

Question 16

Exception 2 is what?
And what does it apply to?

Answer 16

Exception 2: except sinks, urinals, and dishwashers - exceeding 1 fixture unit

Applies to:
Drainage piping Vertical 1 1/2

Question 17

Exception 3 is what?
And what does it apply to?

Answer 17

Exception 3: Except six-unit traps or water closets

Applies to:
Maximum Units: Drainage Piping Vertical and Horizontal 2”
Vent Piping: Maximum Units for 1 1/2”

Question 18

Exception 4 is what?
And what does it apply to?

Answer 18

Exception 4: only four water closers or six-traps allowed on a vertical pipe or stack; and not to exceed three water closets or six-unit traps on a horizontal branch or drain

Applies to:
Maximum Units: vertical and horizontal for 3”

Question 19

Exception 5 is what?
And what does it apply to?

Answer 19

Exception 5: based on 1/4 inch per foot (20.8 mm/m) slope. For 1/8 if an inch per foot (10.4 mm/m) slope, multiply horizontal fixture units by a factor of 0.8

Applies to:
Maximum Units: drainage piping - horizontal 4”

Question 20

Exception 6 is what?
And what does it apply to?

Answer 20

Exception 6: the diameter of an individual vent shall be not less than 1 1/4 inches(32mm) nor less than one-half the diameter of the drain to which it is connected. Fixture unit load values for drainage and vent piping shall be computed from table 702.1 and Table 702.2(2). Not to exceed one-third of the total permitted length of a vent shall be permitted to be installed in a horizontal position. Where vents are increased one pipe size for their entire length, the maximum length limitations specified in this table do not apply.

Question 21

Exception 1 is what?
And what does it apply to?

Answer 21

Exception 1: excluding trap arm

Applies to:
Maximum Units: Drainage Piping