ECN Forum Forums General Topics of the Trade General Discussion Area exit signs

Would that happen to be the Bella Terra Cinemas?

I did the audio racks and rough installs for that cinema.

I have an LED exit sign over the front door in my apt. It has a battery backup built in too. Nifty.

That is an interesting idea with the diodes. I want to try that with one or two of the fixtures in my house to see how that works out.

I have a large, antique sign that says "fire escape" hanging over one of the windows in my house as a joke. (1st floor, right next to a door) I pulled it out of a building that was going to be completely renovated. It has 2 lampholders, which were wired in series. on top of that, the fixture was wired for 120 volts but had 240 volt bulbs in it. It barely glowed at all. It looked cool, though, and the original bulbs are still (sorta) glowing strong.

using 240v lamps was the trick we used to get more life out of a bulb change, we used them in stairwells and exit signs and in some places to shine on the fire extinguishers
line voltage just burned out too fast between annual re-lamping cycles.

I still have a few that I use as night lights on my garage and barn

Yeah, ok, but 240V bulbs in series wired to 120V? That means each bulb only gets 60V... now that'll make for a long life

Zapped:



The Nuclear Exit Signs (or "Self-Luminous" Exit Signs) are typically the "Radioluminescent" types, which use the Radioactive Element "Tritium" inside the sign's tubes.

Some may be, or could have been, "Phosphorescent", which uses the same materials as "Glow-In-The-Dark" stuff does, and may be in conjunction with some type of "Photoluminescent" material - a material which absorbs light, then slowly re emits it.

I am more familiar with the Radioluminescent" types, and more specifically, using Tritium instead of Radium + Copper-Zinc Sulfide Paints.

.........HOW IT WORKS...........

The light is produced by the "Bombardment" of ionizing radiation (beta particles, for example).
When the Tritium decays, it produces light.

The half life of Tritium is something like 12 years, so on average a Nuclear Exit Sign using Tritium will last over 20 years.

*** A little Tritium Trivia ***

Tritium ( symbol = T or ³H ) is a radioactive isotope of Hydrogen.
Tritium decays into helium-3 in a single reaction, where the original ³H becomes ³He and releases one electron and one antineutrino.

Tritium cannot penetrate human skin, so the only way to absorb it is by inhailation or ingesting it.

Tritium occurs naturally - from cosmic rays interacting with gases in the atmosphere (Nitrogen, for example); and it is produced in Nuclear Reactors.
It is occasionally a direct product of nuclear fission, and is also produced in reactors moderated with "Heavy Water" (Deuterium).
When the deuterium moderator captures a neutron, a small amount of Tritium is produced.

Tritium is also used with Nuclear Weapons, as the "Fission Primary" (kind of like a Nuclear "Booster" or Blasting Cap), to aid in the detonation of a Plutonium or Uranium weapon.

I have only basic knowledge on this subject - and this information was stored away in my archives, from many years past!
Nonetheless, I might do some research on Tritium + Radiolumenescent materials soon, and post more data later.

Scott

p.s. please pardon any spelling errors!

Thanks for the wealth of info Scott. I think they were definately radioluminescent that I dealt with, as rumor had it that a government agency (nuclear commision?)showed up once when a bunch of the new signs went missing from a storage container on a new build. They interviewed all the company heads and security staff, as I recall.

mxslick - actually, the theaters I was building at the time were Edwards Cinemas. They have since been bought out, I believe by Regal. At the time (around '97 to '00), they were on a building spree, including CA, ID, and Texas. They dumped a ton of money into some very nice theaters, and it's probably what unfortunately buried them. It was certainly fun, however, to get shipped around the country and work with some very cool ECs in different states. We did a lot of the specialized lighting, IMAX, and general finish work. It was a cool gig while it lasted.

Texas Ranger,

it was written that his were wired in series, from my experiences the exit signs were fed with 120v and in Chicago, were ALL fed from a fused panel. but the lampholders were not series'd if that were the case ordinary lamps would have worked just fine for longevity

it was their Code through the late 70s and may still be a requirement

my apologies for adding my own brand of confusing Hoosier gibberish....

It's 2008...and it's still required in Chicago (unless you can get a variance to use breakers).

Yep, but napervillesoundtech definitely had two 240V bulbs series wired to 120V. Pretty dim I guess.

I think the non-electric exit signs I've seen here are photolumiscent rather than radioactive. They're basically flat sheets of some kind of plastic stuck to the wall.

A friend of mine had radioluminiscent paint dating back to WWII in his basement until very recently... now that was cool! Only white walls as long as the lights were on, but in the dark you'd suddenly see a glowing green horizontal line maybe 5 feet from the floor and the word "Ausgang" (Exit) in some script writing painted next to the door.

I saw paint like that on a U.S. Navy ship a few years ago.

A part of the bulkhead was painted with paint that glowed in the dark; and the numbers telling you where you were had been painted in black letters on it.

When the lights went out, you could see the tags easily on the glowing background and knew just where you were in the ship (and how to get where you really wanted to be).