I am involved in a production that will have confetti (tissue paper) falling from a snow bag above the 1st LX, so far no one has mentioned soaking the paper in fire retardant...since the lighting fixtures will certainly be in the line of fall? should I be concerned?
Yes, Confetti will get into everything. If there is even a remote chance of the confetti getting into the fixture have it flame treated, alternatively move the effect below the first electric or away from the electrics.
If your doing it all from line sets I would put the holes for bag on the opposite side of the electric, and fly it in even or just below the electric right before the effect happens. You could also fly in the border in front of everything a little more to help with masking the bag while it's down.
Most commercial confetti is already colorfast and flame resistant, and if it's not, buy from someone else. I know that our confetti line (www.ultimateconfetti.com) is, and we do regular batch testing to ensure that it will not hold a flame. That's not to say that it won't scorch and burn away or that a large amount in high temperatures might not be a problem as most everything is flammable under the right circumstances.
I would definitely not recommend it above electrics because it can and will find its way in to all kinds of places. Larger confetti (1.75x.75) is less likely, but it can still slip in to lighting fixtures and other types of gear. Keep in mind also that Mylar (metallic) confetti is known to be electrically conductive, so be aware of that.
If directly above an electric, I'd say you're in for bad juju. If you can get a foot upstage or downstage of the electric, and have the holes of the snow bag directed away from the electric, you're in better shape.
Be aware you'll be finding confetti all over the place for awhile. I recommend when the event is done to take an air hose to your lights and circuit distribution strip and other nearby rigging and blasting any remaining confetti away, If you don't make a diligent effort to clean up remaining confetti, you'll find it falling down during shows for months to come. Sometimes the pieces will fall a week later. I've seen confetti fall from above months after an event used it.
Or 20 years later...
Ok, plastic snow, but same difference.
I second being sure to blow out everything extremely well after the event - not just to avoid it falling later, but also to make sure that nothing will melt or smoke or any of that good stuff later down the line.
Keep in mind flame retardant means if flame is introduced, the piece could burn but if the source is removed it should stop burning. If your sitting the stuff on (or inside) a lighting fixture it will burn. It will smolder. It could produce flame. That flame could jump. Don't do this.