Basic electrical Information & Safety Issues - LEDs

By Alan Tannous
LEED AP and Safety Trainer
Alan Tannous publishes a monthly to Schneider Electric employees touching on electrical basics and safety. The following is his Issue 19-3 from Sparky's Corner.

Well we certainly support the use of LEDs for improving lighting efficiency and energy savings, but what I am asking is do we need to literally physically support these fixtures, specifically in a suspended ceiling? We often replace old florescent lay-in fixtures with new LED lay-ins. Many existing installations were installed prior to recent code requirements or were installed incorrectly not complying with Code requirements. So, when we install new fixtures we need to install them in a Code compliant manner. Are there NEC Code requirements for the support of Luminaires (fixtures) in suspended ceilings or can we just set them into the ceiling grid and light um up?

Well, of course you know the answer is yes, we do have to comply with Code requirements or I wouldn’t be writing this newsletter, right? So here goes:

Thanks to Mike Holt, I just recently read his article in EC&M magazine specifically addressing this issue and Mike has agreed to allow me to reproduce his illustration and some Italicized excerpts from his article. Thanks Mike, much appreciated and saved me a lot of time putting this together. Please refer to 2017 NFPA 70 Article 300.11 Securing and Supporting (B) Wiring Systems Installed Above Suspended Ceilings. Also refer to Article 410, Part IV for proper support of Luminaires and Chapter 700 for various Articles on support for Fire Alarm and Fiber Optic Cables. Chapter 8 for requirements for Com Cables.

Of course, existing suspended ceilings need to be securely attached together and secured to the building structure at the appropriate spacing to comply with building codes. Faulty grid systems or loose supports need to be addressed to ensure proper ceiling support before we install new fixtures.

Luminaires (Code speak for fixtures) must be attached to the suspended ceiling framing members with screws, bolts, rivets or clips that are listed and identified for such use (Sec. 410.36 (B)) see above.

A sticking point in many discussions is whether the fixtures must have independent support wires for these luminaires or is being securely attached to the grid enough? Well, to comply with NEC Code, they do not require independent support wires, if the ceilings are not fire rated. But Building codes that cover earthquake zones do require independent support wires attached to grid mounted fixtures. Why is this you may ask. During an earthquake they may come loose from the grid, but If independently supported will most likely remain in the air hanging from the support wires attached to the structure and directly to the fixture. So, the extreme shaking ceilings do not release lay-in fixture missiles to further terrorize and endanger occupants. It is a great safety feature. The Building Department in the community where the work is being performed, will be able to let you know the requirements for that installation location.

Additionally, we do run into applications where the entire ceiling is removed due to updated finishes or other considerations. In these cases, we must be very diligent to assess our liability to re-support all existing open wiring and conduits in old ceilings that may (read most likely) have used the ceiling support wires for supporting all manner of installations. We will most assuredly be expected to temporarily support and then update new supports to comply with current codes for all systems to remain, when the new ceiling goes in. See some of the NEC Articles referenced above for details for different systems. These systems may be Fire Alarm wiring, Data and Com wiring, security system wiring, PA system wiring and all manner of branch circuit conduits that are currently using the ceiling support wires for support. Using ceiling grid support wires for other system supports used to be legal in times past, but no longer is allowed due to load limits and deflection of the ceiling from using tension type clips to support stuff. You now need to put colored, tagged or otherwise effectively distinguished independent support wires for everything not part of the ceiling assembly including the ceiling support wires. Please see Article 300.11(B)(1) and (B)(2) for Fire-rated and non-Fire rated ceiling assemblies.

In closing, when we approach a new project, we need to analyze and clarify new fixture support and above ceiling conditions, existing systems and supports, so we don’t open a can of worms or at least we can charge for the cost of wrangling those worms once the can is opened.

I may follow this up with a newsletter covering colored LEDs and the ever-present topic of Human Centric Lighting. Bet you can’t wait … right?

Alan W. Tannous
Construction Service Manager
LEED AP - National SME Electrical Estimator
Master Electrician/Sr Estimator/Safety Trainer

Alan has been with Schneider Electric for almost 11 years as a Mechanical/Electrical Estimator and National SME for Electrical Projects including Microgrids and other large Distribution System Replacements and Upgrades. He holds a Masters License and is a licensed Electrical Contractor.