Welcome to the new Film-Tech Forums!
The forum you are looking at is entirely new software. Because there was no good way to import all of the old archived data from the last 20 years on the old software, everyone will need to register for a new account to participate.
To access the original forums from 1999-2019 which are now a "read only" status, click on the "FORUM ARCHIVE" link above.
Please remember registering with your first and last REAL name is mandatory. This forum is for professionals and fake names are not permitted. To get to the registration page click here.
Once the registration has been approved, you will be able to login via the link in the upper right corner of this page.
Also, please remember while it is highly encouraged to upload an avatar image to your profile, is not a requirement. If you choose to upload an avatar image, please remember that it IS a requirement that the image must be a clear photo of your face.
Thank you!
I found this old photo of me in my "Xenon Suit" a couple of days ago. I don't recall exactly
when it was taken, but the old flip-phone on my hip means it was taken some time ago. XenonSuit_JP.jpg
Also, on the earlier topic in this thread about saving carbon dirippings- - Yes, when I was working an arc
booth in New York in the late 1960's thru mid 70's, we always saved the copper drippings, usually in
old coffee cans (back then ground coffee or whole coffee beans were mostly sold vacuum packed in
metal cans) and once a year or so, one of the business reps from The Union would come & take the
'drip cans' with him when he made a booth visit/inspection. I was always told that the money from
the recycled copper went to support The WIll Rogers Hospital in upstate NY, a charity which most
of the I.A. entertainment unions supported in some way or other at that time. (The other charity oten
supported by various entertainment union donations or fund raisers was Variety Clubs International)
This is probably bad, but I just do the face shield. I also wouldn't change a lamp without wearing a long-sleeve shirt (or jacket with long sleeves).
Note that I've mostly dealt with 2k and 3k xenons, not the really big ones. I'd wear something more substantial for changing 4k and 5k lamps.
I've never had a problem when changing xenons, but I did have a 2k blow up during a show once. That one had about 1500 hours on it. It sounded like a giant plate-glass window breaking and made a mess. After that, the theatre stopped buying LTI xenons.
Sony used to provide a training video, showing the impact a dropped xenon lamp had on the dummy. Not something to live up to. So they recommended a full cover suit, that looked more or less like an Nasa astronaut thing, than a technicians clothing. And I seem to remember, it had an order number on that. So it was in the catalog around 2010, when xenon projectors were sold.
Small lamps are as dangerous as larger ones, the ratio of pressure to glass is similar, so do not underestimate 2 kW bulbs.
According to Dr. Kugler, lamp developer at Osram many years ago, most damage occurred to lamps carelessly laying on a desktop, thereby scratching the glass surface, making it prone to breakage along the scratch. I assume, this was from personal experience of a factory guy.
I have always assumed that the damage an exploding xenon lamp can do is related to the gas laws.
The Ideal Gas Law being: PV=nRT.
P = pressure
V = volume
n = amount of substance in moles.
R = the Gas Constant
T = temperature in kelvins.
If all other things remain the same, increasing the temperature (approx. 20 C to 250 C or approx. 290 K to 520 K) increases the pressure proportionally. In this case, the pressure multiplies by a factor of approx. 1.8.
If you have approx. 10 atmospheres of gas pressure when the lamp is cold (room temp.) you will end up with 18 atm. when the lamp gets hot. So, if your lamp starts at approx. 147 psi. (1 atm @ 14.7 psi. X 10 atm. = 147 psi.) when cold it will have a pressure of approx. 265 psi. when hot.
Therefore, a 1-inch piece of flying glass would be propelled with 265 lb. of force when the lamp breaks. That's nothing to trifle with!
A smaller lamp would have a different amount of gas and a different volume, compared to a larger one but the amount of force would likely be similar. The amount of "stuff" that gets propelled outward might be less in a smaller lamp but the force it gets propelled at might be greater.
Overall, I'd guess that the amount of damage that a small lamp can do would be similar to a larger lamp, all things being equal.
I think it would be like the old conundrum: "Would you rather be struck by a ping pong ball traveling at 1,000 mph. or a bowling ball traveling at 1 mph?"
I wouldn't want to be struck by either one!
Neither would I care whether its a small lamp or a large lamp. I wouldn't want to be near either one if they explode!
A person would be likely to be hurt just as badly, no matter the size of the lamp.
Sony used to provide a training video, showing the impact a dropped xenon lamp had on the dummy. Not something to live up to. So they recommended a full cover suit, that looked more or less like an Nasa astronaut thing, than a technicians clothing. And I seem to remember, it had an order number on that. So it was in the catalog around 2010, when xenon projectors were sold.
Small lamps are as dangerous as larger ones, the ratio of pressure to glass is similar, so do not underestimate 2 kW bulbs.
According to Dr. Kugler, lamp developer at Osram many years ago, most damage occurred to lamps carelessly laying on a desktop, thereby scratching the glass surface, making it prone to breakage along the scratch. I assume, this was from personal experience of a factory guy.
I will clean out a booth now and again to get bulbs out of harms way and have a bulb popping session in a safe spot in my yard. Invariably, the D cinema bulbs are louder and more explosive. Eye protection is critical of course and our eyes are definitely most vulnerable. What take any risks? Any respectable hardware store has face shields in stock.
Seeing it, it is actually quite scary, and reminded me of the fact, that digital bulbs, for reason of better arc stability and efficiency run on 2.5 times the internal pressure, theatre bulbs had. Therefore a different hazard class.
Seeing it, it is actually quite scary, and reminded me of the fact, that digital bulbs, for reason of better arc stability and efficiency run on 2.5 times the internal pressure, theatre bulbs had. Therefore a different hazard class.
That is the best thing that I have seen in ages!!! Thank you for the laughs.
That is the best thing that I have seen in ages!!! Thank you for the laughs.
So Japanese. I was happy to recover it on the old machine, within the training seminar stuff from that time.
Maybe its worth archiving in the warehouse...
They couldn't tell me where to buy that fancy astronaut gear to perform the lamp change.
If you have other employees changing lamps having the safety outfit is good insurance. I never used one in 42 years of changing lamps, just wore my glasses. Never had any issues either.
I recall seeing a pretty scary bulb explosion video somewhere several years ago which started out with a shot of a xenon bulb and some platter-jockey projection kid showing what a Xenon projection bulb looked like. There was a close-up of the bulb sitting on a table, as a voice described the bulb and how it worked. At some point a hand came into the picture and he started to pick the bulb up- - perhaps so the camera could get a closer shot of it, and I'm not sure what happened next, but as he started to pick up the bulb, it exploded. The video ended shortly after that, but not before you saw a bloodied hand enter the picture as the camera was shut off. I must admit, that prior to seeing that video, I sometimes would take some safety shortcuts when changing a bulb. But after seeing the force of that bulb explosion, and realizing how easily a flying shard of glass could puncture a major blood vein or eyeball, I NEVER changed another xenon bulb without full protection. Once, I found myself needing to do an emergency bulb change at a theater which had a face mask, but couldn't find their protective vest or gloves. I didn't have time to pull one from another theater, so I ran home & borrowed a heavy pair of welding gloves from a neighbor, and I brought two heavy winter jackets back with me, & put both of them on backwards to protect my chest & arms. I figured it was better than nothing- - and after seeing that video I didn't want to take any chances 'unprotected'.
> I don't recall exactly where I saw that video. It may have been on You-Tube, but I've tried searching for it with no luck. Maybe it's no longer there, or I need to try different search terms.
When one of the theaters I worked for downgraded from film to digital projection a decade ago, I was asked to dispose of awholebuncha old xenon bulbs that were up in the booth. Almost all of them were in their original cardboard boxes. Some had the protective shield around them, some did not. For multiple reasons, I knew I didn't want to just toss them in the trash, so my trick to get rid of them was to drop them from the 2nd story balcony fire escape exit into the alley below. . (The alley was closed off from the street by a one-way iron emergency exit gate, so I didn't have to worry about the bulbs landing on anyone below) Some of the bulbs exploded with enough power to even poke a hole or two in their protective coverings.
If you have other employees changing lamps having the safety outfit is good insurance.
Don’t forget that it is the employer’s responsibility to provide PPE where it is needed and employees are required to use it.
So says Federal labor regulations and most if not all State laws, too.
If YOU don’t wear PPE when changing xenons, that’s YOUR business but, as an employee, it would be your requirement to do so. You could be written up or fired for disobeying. If there is an accident where you are injured and it can be shown that you are guilty of willful misconduct, gross negligence or insubordination, your Worker’s Compensation and/or Unemployment Compensation benefits could be jeopardized.
Wearing a flack jacket, gloves and face protection is not THAT difficult or inconvenient. It’s nothing like the “moon suit” that I often had to wear in the plating shop.
There is no good reason not to wear PPE when changing xenon lamps.
The proper gear is also not expensive. I made sure each of our booths had enough gear for two people so we can train new projectionists, with jackets and gloves in two sizes.
These are from a series of video Osram shot at the Boston Light And Sound warehouse a couple of years ago showing how to handle and troubleshoot XBO projection lamps!
Tweet
)
Comment