The maximum number of conductors permitted in any surface nonmetallic 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 388 presents the rules for surface nonmetallic raceway. As noted in 388.22, "The number of conductors or cables installed in surface nonmetallic raceway shall not be greater than the number for which the raceway is designed."