Combustible material adjacent to luminaires cannot be subjected to temperatures exceeding which value?

• A. 90°C
• B. 60°C
• C. 75°C
• D. 110°C

Answer: (A)

The main idea is to limit the heat that nearby combustible materials can be exposed to in order to prevent ignition from a luminaire. Standards specify a maximum of 90°C for materials adjacent to luminaires, so even under worst‑case heat from the fixture, nearby combustibles like wood, paper, or insulation won’t reach temperatures that could start a fire. Values like 60°C or 75°C aren’t the required limit, and 110°C would allow more heat than is considered safe for surrounding materials. If a installation could experience higher surface temperatures, you’d need a fixture with a higher temperature rating or additional clearance/shielding.