Carbon Arc MSDS

Does anyone out there by chance have an MSDS form for Carbon Arc rods?

Even the manufactures don't seem to have them anymore. I'm mostly interested in the chemical makeup of the smoke. Thanks in advance

Erik Messerschmidt
DP • Gaffer
Los Angeles, CA

Erik Messerschmidt writes:

>Does anyone out there by chance have an MSDS form for Carbon Arc >rods?

Arc Carbons pre-date MSDS requirements. Air-carbon arc gouging is still extensively used in welding so a welding supply house should have the MSDS for those carbons, but these are pure carbon/graphite.

Another source of data sheets might be Cinema Carbons in Sidney, New York.

These follow spot and projector carbons are also very close to pure carbon and graphite with some trace chemical additives like boron for color.

The negative carbons are copper jacketed, but most of that melts away before it reaches the arc point with a minimum of fuming.

If you're concerned about breathing the smoke, it's probably a good idea to avoid it, but it's not inherently unsafe. Air-carbon arc gouging produces some carbon dioxide, a little carbon monoxide, ozone and nitrogen dioxide.

Brian Heller
IA 600 DP

Hi,

>If you're concerned about breathing the smoke, it's probably a good >idea to avoid it, but it's not inherently unsafe. Air-carbon arc gouging >produces some carbon dioxide, a little carbon monoxide

I was once told, by a crusty old projectionist, that carbon arc smoke was lethal due to the high concentration of CO. It's hearsay, but I'd be very cautious.

Phil Rhodes
Video camera/edit
London

Phil Rhodes writes :

>I was once told, by a crusty old projectionist, that carbon arc smoke was >lethal due to the high concentration of CO. It's hearsay, but I'd be very >cautious.

If it were so lethal, how did he get to be an old projectionist?

I'll bet he smoked, too.

Brian Heller
IA 600 DP

Hi,

> If it were so lethal, how did he get to be an old projectionist?

Because all carbon arc projector systems (and most Xenon ones, for the heat issues) are ducted outside for this very reason. It would quickly become impossible to see across the room otherwise!

Phil Rhodes
Video camera/edit
London

>I was once told, by a crusty old projectionist, that carbon arc smoke was >lethal due to the high concentration of CO. It's hearsay, but I'd be very >cautious.

True enough, but obviously much more lethal in a small projection booth than in an arena or a large stage or outside. A badly tuned kerosene heater or a pile of charcoal briquettes in an enclosed space can be lethal too.

Mark Weingartner
LA based

Mark Weingartner writes :

>True enough, but obviously much more lethal in a small projection >booth than in an arena or a large stage or outside. A badly tuned >kerosene heater or a pile of charcoal briquettes in an enclosed space >can be lethal too.

If you could get a badly tuned kerosene heater or a pile of charcoal briquettes to produce as much light as a carbon arc, you could rest assured that the heater or the briquettes were operating at a level of efficiency that would negate any worries about carbon monoxide.

Air-Carbon arc welding processes, which have been thoroughly analysed as to safety, and are very similar to carbon arcs, produce negligible amounts of CO. The considerable amounts of electric current involved in both, vaporize the carbons. It is not a combustion process. There is more atmospheric CO present on a busy street than there is anywhere near a carbon arc.

An MSDS for welding carbons is at :

www.esabna.com/msds/50.pdf

When you compare the MSDS of standard arc welding rods to carbon arc, then you will get an idea of the relative hazard levels.

Brian "don't eat the carbons" Heller
IA 600 DP

Interesting...while I don't think they are still in the carbon arc lighting game, Carbone Lorraine was one of the manufacturers, along with Union Carbide, of arc trims for projectors and etc. You might be able to hunt them down through their American subsidiary Carbone America.

One component of the smoke is undoubtedly caused by the vaporization of the copper jacket on the anodes. I don't think we are supposed to breathe copper vapour, though God knows how many of us who ran carbon arc spotlights at concerts without exhaust systems on our lamps did.

Jeeze ... between all the solvents and all the metals I've worked with, I wonder what I would have been able to achieve without all the toxins.

Mark Weingartner
LA based