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Seismic Applications for Lighting Fixtures

John Buchmann

Registered User
Mar 15, 2020

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)?

I cannot see the table. You did not indicate the source of the table.

The IRC does not contemplate suspended ceilings thus you should look to the IBC.

While suspended acoustical ceilings are generally more of a problem all suspended ceilings should be braced.

Besides preventing lighting fixtures from falling the concern with suspended light fixtures is that they will sway enough to bang against something else, including other light fixtures, thus causing something to fall. If the swaying light fixture cannot hit up against something else then the need for sway bracing may not be needed. There does not appear to be a hard rule but if each suspended item can sway 45 degrees from the vertical and not hit anything I do not see a problem.