Answer Key: Self-Test D-1.8

1. Figure 2P-28

Table 1 Answers
Letter Name Hydraulic Load (FU) Length Size
A Fixture drain 4 N/A 3 in.
B Branch 12 N/A 4 in.
C Branch 16 N/A 4 in.
D Fixture drain — Sized as a wet vent — Acting as a relief vent 1 N/A 2 in.
E Branch 25 N/A 4 in.
F Circuit vent 20 11 m 1.5 in.
G Continuous vent — Acting as a relief vent 5 3 m 1.5 in.
H Branch vent 25 11 m 2 in.

2. Figure 2P-29

Table 2 Answers
Letter Name Hydraulic Load (FU) Length Size
A Branch 18 N/A 4 in.
B Branch 42 N/A 4 in.
C Branch 66 N/A 4 in.
D Fixture drain — Acting as a wet vent 1 N/A 2 in.
E Branch 73 N/A 4 in.
F Circuit vent 66 16 m 3 in.
G Additional circuit vent N/A N/A 2 in.
H Branch vent 66 16 m 3 in.
I Relief vent N/A N/A 2 in.
J Continuous vent 7 4 m 1.5 in.
K Branch vent 73 16 m 3 in.

3. Figure 2P-30

Table 3 Answers
Letter Name Hydraulic Load (FU) Length Size
A Trap arm — Fixture drain 4 N/A 3 in.
B Branch 10 N/A 3 in.
C Branch 20 N/A 4 in.
D Branch — Acting as a relief vent 2 N/A 1.5 in.
E Branch 26 N/A 4 in.
F Circuit vent 24 13 m 2 in.
G Dual and continuous vent —  Acting as a relief vent N/A N/A 1.5 in.
H Branch vent 26 13 m 2 in.

4. Figure 2P-31

Table 4 Answers
Letter Name Hydraulic Load (FU) Length Size
A Trap arm — Fixture drain 6 N/A 3 in.
B Branch 18 N/A 4 in.
C Fixture drain — Sized as a wet vent — Acting as an additional circuit vent 1 N/A 3 in.
D Branch 30 N/A 4 in.
E Branch 43 N/A 4 in.
F Branch 67 N/A 4 in.
G Branch 67 N/A 4 in.
H Circuit vent 67 23 m 3 in.
I Additional circuit vent N/A  N/A 2 in.
J Branch vent 67 23 m 3 in.
K Relief vent N/A N/A 2 in.
L Branch vent 67 23 m 3 in.

5. Figure 2P-32

Table 5 Answers
Letter Name Hydraulic Load (FU) Length Size
A Trap arm — Fixture drain 6 N/A 3 in.
B Branch 18 N/A 4 in.
C Branch 42 N/A 4 in.
D Branch 54 N/A 4 in.
E Fixture drain — Acting as a wet vent 1 N/A 2 in.
F Branch 62 N/A 4 in.
G Fixture drain — Acting as a relief vent 1 N/A 1.5 in.
H Individual and continuous vent — Acting as a relief vent N/A N/A 1.5 in.
I Circuit vent 54 13 m 2 in.
J Branch vent 55 21 m 3 in.
K Continuous vent 7 7 m 1.5 in.
L Branch vent 62 21 m 3 in.

6. Figure 2P-33

Table 6 Answers
Letter Name Hydraulic Load (FU) Length Size
A Trap arm — Fixture drain 4 N/A 3 in.
B Branch 12 N/A 4 in.
C Branch 28 N/A 4 in.
D Branch 36 N/A 4 in.
E Branch 44 N/A 4 in.
F Stack 169 N/A 4 in.
G Circuit vent 44 30 m 3 in.
H Additional circuit vent N/A N/A 2 in.
I Branch vent 44 30 m 3 in.
J Relief vent N/A N/A 2 in.
K Branch vent 44 30 m 3 in.

7. Figure 2P-34

Table 7 Answers
Letter Name Hydraulic Load (FU) Length Size
A Fixture drain 4 N/A 3 in.
B Branch 28 N/A 4 in.
C Branch 40 N/A 4 in.
D Branch 76 N/A 4 in.
E Branch 88 N/A 4 in.
F Stack 123 N/A 4 in.
G Stack 35 N/A 4 in.
H Circuit vent 88 31 m 3 in.
I Additional circuit vent N/A  N/A 2 in.
J Branch vent 88 31 m 3 in.
K Additional circuit vent N/A N/A 2 in.
L Relief vent N/A N/A 2 in.
M Branch vent 88 31 m 3 in.

8. Figure 2P-35

Table 8 Answers
Letter Name Hydraulic Load (FU) Length Size
A Branch 8 N/A 3 in.
B Branch sized as a wet vent acting as a circuit vent (2 – wv) 69 N/A 3 in.
C Branch 20 N/A 4 in.
D Branch sized as a wet vent acting as an additional relief vent 1 N/A 2 in.
E Trap arm fixture drain 0.5 N/A 1.25 in.
F Branch 45 N/A 4 in.
G Branch 69 N/A 4 in.
H Branch acting as a relief vent 8 N/A 2.5 in.
I Branch 77 N/A 4 in.
J Dual and continuous vent acting as an additional circuit vent N/A N/A 2 in.
K Circuit vent 69 13 m 3 in.
L Branch vent 69 16 m 3 in.
M Dual and continuous vent acting as a relief vent N/A N/A 2 in.
N Branch vent 77 16 m 3 in.

9. Figure 2P-36

Table 9 Answers
Letter Name Hydraulic Load (FU) Length Size
A Fixture drain 4 N/A 3 in.
B Branch 8 N/A 3 in.
C Branch 12 N/A 4 in.
D Branch 20 N/A 4 in.
E Branch 39 N/A 4 in.
F Stack 39 N/A 4 in.
G Stack 19 N/A 3 in.
H Fixture drain 3 N/A 3 in.
I Branch 15 N/A 3 in.
J Stack 4 N/A 2 in.
K Branch 1 N/A 2 in.
L Branch 3 N/A 2 in.
M Circuit vent 20 33 m 2 in.
N Relief vent N/A N/A 1.5 in.
O Circuit vent 15 26 mm 2 in.
P Branch vent 20 33 m 2 in.
Q Branch vent 35 33 m 3 in.
R Circuit vent 4 10 m 1.5 in.
S Branch vent 39 33 m 3 in.

10. Figure 2P-37

Table 10 Answers
Letter Name Hydraulic Load (FU) Length Size
A Fixture drain 4 N/A 3 in.
B Branch 12 N/A 4 in.
C Trap arm — Fixture drain 2 N/A 2 in.
D Fixture drain 2 N/A 3 in.
E Branch 18 N/A 4 in.
F Trap arm — Fixture drain 1 N/A 1.25 in.
G Fixture drain 1 N/A 2 in.
H Branch 3 N/A 2 in.
I Branch 21 N/A 4 in.
J Trap arm — Fixture drain 1.5 N/A 1.5 in.
K Branch 3 N/A 2 in.
L Branch 25.5 N/A 4 in.
M Stack 107 N/A 4 in.
N Sanitary building drain 132.5 N/A 4 in.
O Relief vent N/A N/A 1.25 in.
P Circuit vent 4.5 30 m 1.5v
Q Branch vent 4.5 31 m 2 in.
R Branch vent 10.5 31 m 2 in.
S Circuit vent 6 22 m 1.5 in.
T Combined relief vent N/A N/A 1.5 in.
U Circuit vent 12 21 m 2 in.
V Branch bent 22.5 31 m 3 in.
W Branch vent 25.5 31 m 3 in.
X Branch vent 3 24 m 1.5 in.
Y Relief vent N/A N/A 1.25 in.
Z Circuit vent 3 24 m 1.5 in.

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