We are a foundry that makes rather large Copper based alloy castings.  Our flagship alloy is Nickel Aluminum bronze (C95800).  For over a year, we were bothered by high levels of Cadmium in the air sampling done by our industrial hygiene people.  At first, they picked up a sample of our metal and had it analyzed and found no Cadmium.  We went crazy searching high and low for the source of the Cadmium.  I then found standards available with a suitable range of Cadmium that I could calibrate my spectrometers to measure for Cadmium as part of the normal analysis of the heats.  I was then able to match the heats where the hygiene people found high levels of Cadmium in air samples to the heats where I also found elevated levels of Cadmium.  I searched further and found that SOMETIMES there are SOME ingots with elevated levels of Cadmium.  Now that I can measure for Cadmium, I can take steps to control it.  One of those ways is to mandate a maximum for Cadmium in our purchase specs for ingots and to verify such by chemical analysis the incoming ingots.

I have tried to extend the analysis for Cadmium to our other cast alloys.  We also make castings using Copper Nickel alloys, Copper Zinc alloys, and Coppr tin alloys.  To do that, it is necessaary to have chemical standards in the same alloy matrix as the alloy being analyzed..  Unfortunately, there is a very limited quantity of standards available with a range of Cadmium in other Copper based alloy matrices.  I even have the president of one of the standard suppliers searching the world for standards.  It is desired to have Cadmium range from nil to about 0.10 percent in the various alloy matrices.

 Maybe one or more of the foundry professional societies (AFS, NFFS, etc.) could spopnsor an effort to have such standards manufactured.  This would be very helpful to foundries trying to meet exposure limits for Cadmium.