Seismic Applications for Lighting Fixtures

[vidividi12]

Hi,

I have searched about seismic applications for lighting fixtures and I found the text below. Can I use this table for conventional ceilings or do these requirements apply only to suspended acoustical ceilings? Should I use four seismic cables for each luminaire (even for circular luminaires weighing 0.8 kg)?

 

[tom baker]

This is a building code issue, but there be some who are familar with the requirements and may reply.

 

[RD35]

It has always been my understanding that any fixture which is primarily supported by the ceiling grid on a lay-in style acoustical ceiling system is subject to being dropped on a building occupants head in a seismic event because the ceiling grids usually fall apart thereby allowing the fixtures to fall. Grid tiles and support members are so small and light weight they are not considered a hazard. But light fixtures are definitely a hazard in an earthquake. Hence the requirements for this secondary suspension system. I have seen video footage of an earthquake from a surveillance camera in a large office with a suspended ceiling. After the earthquake the ceiling tiles and most of the grid was laying on the floor. The light fixtures stayed put hanging on their seismic wires. After seeing that video I was totally sold on the idea.

 

[electrofelon]

It has always been my understanding that any fixture which is primarily supported by the ceiling grid on a lay-in style acoustical ceiling system is subject to being dropped on a building occupants head in a seismic event because the ceiling grids usually fall apart thereby allowing the fixtures to fall. Grid tiles and support members are so small and light weight they are not considered a hazard. But light fixtures are definitely a hazard in an earthquake. Hence the requirements for this secondary suspension system. I have seen video footage of an earthquake from a surveillance camera in a large office with a suspended ceiling. After the earthquake the ceiling tiles and most of the grid was laying on the floor. The light fixtures stayed put hanging on their seismic wires. After seeing that video I was totally sold on the idea.

Except now with LED fixtures, and ceiling tiles made from drywall, the tiles are heavier than the fixtures so it doesn't make much sense to me.