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Cadmium Exposure

I am looking for objective evidence in the manner of an industry study that cadmium is not dispersed into the air, unlike chrome as the result of mechanical plating. I have some associates that have been informed poorly and you simply can't tell them otherwise. I've been to the OSHA website and while they reference the limited exposure they do not implicitly state that cad does not enter the air. Thank you for any assistance.

Korey M Frost
AEROSPACE - Warren, Michigan
2006

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January 11, 2011

Korey,
Technically you may be correct, however please consider the Cadmium exposure is not just limited to the manufacturer's site and effects upon your product. Down stream pollutants of salts - residuals from the plating bath, and then during burn off at iron smelting cause a lot of issues as well.

Is the cost of containment, for the lifetime of the amount of metal used and the residuals, worth the economic value ?

Paul Barnhart
- lake in the Hills, Illinois USA

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January 13, 2011

Hi, Paul.

I am not sure if it's possible to make such determinations. But if we have been successfully applying cadmium to critical aerospace components for many decades, and it has delivered safety and reliability according to the known benefits of cadmium plating (compatibility with aluminum, freedom from stick-slip, corrosion resistance, cathodic protection, freedom from gummy corrosion products, etc.), is it prudent to substitute a zinc alloy that we "think" will perform as well on a vital aircraft component, or is it reckless?

My personal feeling, and only a personal feeling, is that we can easily and safely eliminate the big non-critical uses of cadmium plating without putting people at risk, thereby solving 99 percent of the downstream exposure problem; so it might be prudent to keep cadmium on those rare, specialized, life-critical components until we have a few decades of experience showing that zinc alloys can truly and safely replace cadmium over the long haul.

... which brings us back to needing the answers to questions like Korey's.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey