Health issues related to grinding chrome

A. Hi Doug. My personal belief and limited experience is that 400 °C isn't all that hot. I imagine chrome plated motorcycle exhaust systems get hotter, and continuous casting molds in steel mills much hotter. Myself, I wouldn't worry about it ... but there's a difference between personal philosophy and offering advice for others :-)

I think we've entered a time where, assuming this is not a one-time assignment, testing rather than guessing is probably called for. If it's a one-time thing you should probably read the current regulatory thinking -->
... and decide from that that whether you feel there is no reason for concern, or decide to be super safe by wearing a welding hood, respirator, or other protection.

Luck & Regards,

Doug,
I remember seeing some paper that after heating to few hundred degrees C, the plated Chrome slightly reduces it's hardness, and at higher temperatures above 600-700 °C it may be oxidized (probably creates some Cr-hex products)

So, your 400 °C looks like a safe zone (unfortunately I cannot find that paper).
Best regards,

Thanks for clearing that up, Brian. That's 2 things I've learned from this board in the matter of a week or so!

A. Hi, Marc. The state changes to zero -- neither hex nor tri.

Regardless of what material is causing a dust or grit or smoke in the air, though, our lungs were not designed to inhale it. A dust mask or better should always be worn if anything is in the air, whether it be chrome or sawdust or truffles.

Regards,

A. The OSHA PEL for chromium metal as a respirable dust is 1 mg/m3, whereas for hexavalent chrome it is 0.005 mg/m3. So it is obviously much easier to be compliant with chromium when it is only present in the metallic form. Any respirable dust is hazardous to some extent, but unless the air is visibly cloudy from all of the dust, it is not likely that you are near the PEL. Still, OSHA likes to see data as proof which means that you should do your industrial hygiene tests. As long as your process doesn't change, you only need to do it once.

A. Hi,

I absolutely agree with Ted and others having responded to this subject, however, I am quite surprised that it is still not "Standard" using masks in any work which relates with Dust, Fumes, etc. even while within limits of OHSA.
Sadly but true, saving on the wrong spot.

Kind regards,

A. Opinions may flood the page but still bottom line, Jon Barrows hit the nail right in the head. In terms of safety and health get the facts and comply with the law.
G. Marrufo-Mexico

Hi. It's going to be one of those rare occasions where I must disagree with Guillermo...

Of course we have to comply with the law -- it's the law. But we can have opinions that differ from the law, and when those opinions suggest that legally mandated practices are inadequate, we should try to pro-actively go beyond them to the extent that the law doesn't prohibit it. Silent Spring would never have been published, and probably the whole environmental awareness movement would have been seriously delayed, had Rachel Carson not had the gumption to tell us how dangerous the bureaucrats were with their carpet bombing of our towns with insecticide and their other foolish but legal practices.

Asbestos is not chemically dangerous to my knowledge, which may be why there were not adequate laws to protect workers from inhaling it. If people had simply accepted the general advice that crap doesn't belong in our lungs, whatever it is, the asbestosis tragedy might have been greatly mitigated.

Closer to home, hexavalent chromium fumes weren't considered carcinogenic until fairly recently, even though we all knew that they were very harmful. I had a terrible row with an architect who insisted that a large canopy exhaust over the whole line, instead of local lateral exhaust, was adequate for a chrome plating line because there were at the time no rules against it.

So I'm going to insist: no solid particles of anything belong in your lungs, which means you should be wearing some sort of dust filtration device if there is any evidence of dusting.

Regards,

A. Hi Robee. Chrome plating is chromium metal, valence state 0; it's neither trivalent (valence state +3) nor hexavalent (valence state +6). Chromium metal is not chemically dangerous; chrome plating is used on various kitchen and serving equipment.

But if you are seeing dust and filings in the area, you should consider wearing a dust mask because that kind of garbage doesn't belong in your lungs (or your stomach). Good luck.

Regards,