Corrected Ampacity = Table 310.16 Ampacity × Ambient Temperature Correction Factor. For a dry location, use the 90°C column for THHN. Ambient Temperature Correction Factor for 100°F = 0.91 for THHN.

Where four or more current-carrying conductors are in a raceway or cable, the conductor ampacities in Table 310.16 in the 90°C column must be adjusted per Table 310.15(C)(1). Where cables are bundled ...