The maximum number of conductors permitted in any surface raceway shall be _____.
a) no more than 30% of the inside diameter
b) no greater than the number for which it was designed
c) no more than 75% of the cross-sectional area
d) that which is permitted in Table 312.6(A)
See answer and applicable Code reference
The correct answer is: b) no greater than the number for which it was designed
Article 386 covers the use, installation, and construction specifications for surface metal raceways and associated fittings. As noted in the first sentence of Sec. 386.22, "The number of conductors or cables installed in surface metal raceway shall not be greater than the number for which the raceway is designed."