Table 310(15)(B)(3)A

[624]

If I have my jboxes less then 24 inches apart let’s say jbox-conduit-jbox-conduit-jbox-conduit, conduit is less then 24 inches apart between jboxes I’m thinking I would not have to do any derating

 

[augie47]

As far as de-rating for conduit fill I would agree, not required.

 

[infinity]

No derating required and you can fill each section of raceway to 60% if there are 3 or more conductors.