What is the maximum weight a ceiling box listed for fixture support can support when using ENT?

A ceiling box that is specifically listed for fixture support has a designated maximum load capacity that is determined during its testing and certification process to ensure safety and reliability. In general, when using Electrical Nonmetallic Tubing (ENT), the maximum weight that a fixture support ceiling box can safely support is 20 pounds. This means that any light fixture or similar device installed on the ceiling should not exceed this weight to comply with safety standards.

The guidelines for weight limits ensure that the installation can withstand the load without risk of failure, which is crucial for preventing accidents and ensuring the long-term durability of the installation. This specification is critical, especially when considering the potential vibrations and stress that could be exerted on the box over time.