An electrician plans to hang a small luminaire directly from a run of rigid nonmetallic conduit in a covered outdoor walkway. How does the Code treat that plan?
- AIt is acceptable wherever the conduit is trade size 1 or larger and is securely strapped on both sides
Trade size and strapping are not a permission. A larger plastic raceway still creeps under sustained load and still softens at elevated temperature, whatever the support spacing.
- BIt is acceptable wherever the luminaire and its lamp together weigh less than 6 pounds
There is no weight threshold in this rule. Even a light fixture applies a continuous load and a lever arm at the fitting, and the conduit is not listed to take it.
- It is prohibited unless the conduit is listed for the support of luminaires or other equipment
- DIt is acceptable in any outdoor location as long as the conduit is schedule 80 PVC
Schedule 80 has a thicker wall for physical damage, which is a separate topic. Wall thickness does not turn the conduit into a listed support for luminaires or other equipment.
Why C is correct
The prohibition is written against the material, not against a weight. Thermoplastic conduit deflects under a steady load and softens in heat, and a luminaire is a steady load hanging in the sun. The Code closes the question by requiring that the conduit itself be listed for supporting equipment before it can carry any.
What this question is testing
This item tests whether you can find a prohibition in the uses-not-permitted section of a raceway article and resist distractors that invent thresholds based on size, weight, or wall schedule.
On the job
Canopies, parking structures, and outdoor equipment yards are where crews are tempted to strap a fixture, a small box, or a photocell to the plastic run that is already there. Over a couple of summers that run bows visibly between supports, and in the worst cases the fitting separates and the conductors take the weight. The correct fix is a strut or a bracket back to the structure, which also gives the fixture a rigid mounting for aiming.
Memory technique
Plastic carries wire, not weight.
Exam tip
For plastic conduit, remember what it cannot do: support equipment, live in hazardous locations, or exceed its listed temperature.
Where to look it up
The rigid nonmetallic conduit article follows the standard layout, with uses not permitted in the .12 section.