Here is a link to "Guide to Electric Motor Bearing Lubrication" by ExxonMobil
http://turbolab.tamu.edu/pubs/Pump23/P23Tut02.pdf

On the very last page, it states

quote:

Safety
*Never clearn the end of the grease gun with your finger
* Do not put your fingers near the nozzle of the grease gune to steady it when injecting grease. It may slip.
*Risks injection injury
*Grease injected under the skin may cause gangrene and loss of the limb

Some more references:

http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1816885&blobtype=pdf

http://www.ejbjs.org/cgi/reprint/43/4/485.pdf

Has anyone heard of this hazard? Is it eliminated by modern grease gun fittings? Is there really a danger that requires us to observe special precaution during greasing related to the possibility of injecting yourself with grease?

I mentioned it to some folks in our shop and they didn't take it very seriously. They had a hard time imagining how grease could really get injected under the skin.

What do you guys think?

I read an article that showed a very nasty infection that was caused by high pressure hydraulic fluid hitting a guy in the arm and getting embedded under the skin. We all know that grease guns can operate at high pressures, but it does seem unlikely that you could get it to flow at a high enough velocity to make it as dangerous as hydraulic fluid shooting out of a pressurize system. I would think that there would be more danger in allowing grease to get embedded into an open sore or wound. I wish I could remember the article because the pictures of this guys arm were very nasty. Does anyone remember seeing this article.

One has to remember that in our litigious society we have to write very broad encompassing statements in an effort to provide protection from a lawsuit. Therefore ExxonMobil, not know the specifics of a grease gun, the pressure, the knowledge of the operator, etc. wrote this very broad safety recommendation.

They can be dangerous under certain circumstances. Noria has an interesting on grease gun safty at http://www.noria.com/learning_center/category_article.a...okgroup=Lubrication2.

Like many things safety related, best that people be aware that things can occur in rare circumstances.

John from PA

quote:

Has anyone heard of this hazard?

There's an old urban legend among heavy machinery operators that is similar to this. To adjust the track tension on many bulldozers you pump grease into a cylinder. This cylinder is never supposed to be put under too much pressure, and you're supposed to use a pistol-grip gun that won't apply more than 6000psi (at least on a JD 450 like I had). The legend goes that some guy used a lever action gun and pumped up the cylinder to somewhere near around 10,000psi. He realized when he tried to run the machine that the track was too tight now, so he went to loosen the grease fitting to let some grease out and lower the pressure. The grease fitting sheared the last thread, shot out of its hole, right up the guy's nose, into his brain cavity, and his head was filled with the spraying grease. He died, needless to say.
That's the legend.
Not hardly likely, but fun to tell and embellish.

A standard lever-arm grease gun _can_ apply 10,000psi. That _is_ a whole lot, and if a tiny squirt shoots out then I suppose it could pierce the skin if your finger was close by. I'd honestly only be worried if I was using a grease needle. A regular fitting wouldn't be worrying me.

Interesting topic on injection risks, we have just done a training on this for all the guys that are involved in using or maintaining Hydraulic systems and one topic came to light was the minimum pressure needed for an injection wound is 1300-1500psi. Considering the grease lines at 6-10,000psi. it has to be viewed as a serious risk.