Chapter 9 Table 4 — Conduit Dimensions

Dimensions and Percent Area of Conduit and Tubing

Trade Size Nominal Internal Diameter Total Area
100%
60% 1 Wire
53%
2 Wires
31%
Over 2 Wires
40%
mm in. mm2 in.2 mm2 in.2 mm2 in.2 mm2 in.2 mm2 in.2
½13.40.5261410.217850.130750.115440.067560.087
¾18.30.7222630.4091580.2451390.217820.1271050.164
123.80.9364450.6882670.4132360.3651380.2131780.275
31.91.2557991.2374790.7424230.6562480.3833200.495
37.51.47611041.7116621.0275850.9073420.5304420.684
248.61.91318552.87411131.7249831.5235750.8917421.150
58.22.29026604.11915962.47114102.1838251.27710641.648
372.72.86441516.44224913.86522003.41412871.99716602.577
84.53.32656088.68833655.21329724.60517382.69322433.475
496.23.786726811.25843616.75538525.96722533.49029074.503
5121.14.7681151817.855691110.71361059.46335715.53546077.142
6145.05.7091651325.598990815.359875213.56751197.935660510.239

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DISCLAIMER: All tables on this site are based on the 2020 National Electric Code. The law under your local jurisdiction may be different than what is presented here. Check your local jurisdiction's laws before attempting to do electrical work.

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