10/20/2026
β‘ CODE QUIZ ANSWER β‘
The correct answer is B) 40%!
Per CEC Table 8, the maximum allowable percentage fill by internal cross-sectional area is 53% for one conductor, 31% for two conductors, and 40% for three or more conductors.
The two-conductor figure is the one that surprises people. It's the tightest of the three, because two round conductors nested in a round raceway leave more unusable space than three do.
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