Lay-i Light Fixtures in a ceiling used for return air

[mikederuby]

We have a project where the ceiling space above a lay-in ceiling is used for return air to the roof top air conditioners. The fixtures used are an LSI direct/indirect 2x4 and 2x2 lay-in static troffer. The inspector is claiming that the fixtures used are not UL listed to be installed in a return air space of the ceiling. Is the inspector correct? I have never run across this in the last 30-years. Is there some new code requirement I am missing?

 

[bigjohn67]

Re: Lay-i Light Fixtures in a ceiling used for return air

"Pleneum rated fixtures" have louvers on the outer edges. A Standard lay in fixtures is not rated for this purpose when used as such.
Have the GC install open grills for the return and you should be fine.

If there is no GC or "open grills" in the ceiling, looks like you should go shopping for the correct fixture.

Maybe cheaper for you to purchase a few "open grills" and install them yourself to provide the proper airflow.

This has been around for many years and nothing new about it.

[ May 05, 2005, 11:00 PM: Message edited by: bigjohn67 ]

 

[mikederuby]

Re: Lay-i Light Fixtures in a ceiling used for return air

The ceiling has open return air grills. The fixtures are not intended as the return air path.

 

[mikederuby]

Re: Lay-i Light Fixtures in a ceiling used for return air

I am specifically referencing NEC article 300-22(c)as it applies to the installation of lay-in fixtures.

 

[infinity]

Re: Lay-i Light Fixtures in a ceiling used for return air

Did he cite a specific code section or just say it was not listed for that use?

 

[mikederuby]

Re: Lay-i Light Fixtures in a ceiling used for return air

No, he has not cited any code. He wants us to prove that the fixtures are listed for installation in the lay-in ceiling. We have contacted the manufacturer and have gotten a letter from their director of engineering stating the fixtures are listed for the intended use. The project engineer is confused also. The manufacturer is just as confused.

 

[steve66]

Re: Lay-i Light Fixtures in a ceiling used for return air

300.22 (C)(2):

I think it reads like this:

Electrical equipment with a metal enclosure....shall be permitted....

There is no requirement that the fixture be listed if it has a metal enclosure.

If the fixtures have a non-metallic enclosure, then that enclosure has to be listed for use in an air handling space.

[ May 06, 2005, 02:12 PM: Message edited by: steve66 ]

 

[tshea]

Re: Lay-i Light Fixtures in a ceiling used for return air

Ask the inspector what his problem is and to cite a specific code violation.
If you have letters from mfg and they state you comply with installation, I don't see the problem.

Once had an inspector hold up a job for a week because he thought my grounding was done wrong. I asked him several times what was wrong. His reply was "don't you take the code classes?" "Yeah I do." "Do you?"
He could not cite a violation and finally released the job after I threatened him and the municipality with a law suit.
If I'm wrong I admit it and fix it and eat humble pie!

 

[ryan_618]

Re: Lay-i Light Fixtures in a ceiling used for return air

The IMC (International Mechanical Code) would be a better code to address this than the NEC. Section 605 provides a flame spread and smoke developed index that items used in "other space for enviromental air". A typical lay-in troffer should meet these values without any problem whatsoever.

 

[john m. caloggero]

Re: Lay-i Light Fixtures in a ceiling used for return air

As an ex inspector, I don't believe the inspector is doing his/her job if they don't cite you the Code section you are violating! Secondly, the space above a dropped or suspended ceiling with lift-tiles is not a plenum, it is "Other Space Used for Environmental Air" and comes under 300.22(C). "Electrical equipment with a metal enclosure such as drop-in fluorescent lighting fixtures (luminaires) are allowed in the other space used for environmental air. Lighting fixtures, motors, transformers, and junction boxes that have metal enclosures are permitted in the other space for environmental air. However, NONMETALLIC ENCLOSURES MUST BE LISTED FOR USE IN THAT SPECIFIC SPACE.