Method 306 - Chromium Emissions Electroplating/Anodizing
|Text of Test Method 306 - Chromium Emissions Electroplating/Anodizing
FREQUENTLY ASKED QUESTIONS (FAQS) for Method 306
Is California Air Resources Board (CARB) Method 425
a suitable alternative to Method 306?
Method 306 is really only applicable to chrome electroplating and
anodizing sources. CARB Method 425 may be used in lieu of Method 306
to test affected chrome electroplating and anodizing sources under
Subpart N (40 CFR Part 63) as long as the caveats in 63.344(c)(2)
are met. If one is testing a source other than a chrome electroplating
and anodizing tank and is trying to determine total chromium,
then we typically recommend Method 29. If one needs to determine
hexavalent chromium from any source other than a chrome electroplating
or anodizing tank, then we recommend SW-846 Method 0061.
In research done in the 1980's, we found that impinger methods like
Method 306 (CARB Method 425 is also essentially an impinger method)
did not give proper results for hexavalent chromium; our conclusion was
that a significant portion of hexavalent chromium was converted to
trivalent chromium during the sampling process. Method 0061 uses
recirculating alkaline reagent to keep the hexavalent chromium in the
hexavalent state during sampling.
Still have questions on this method? Contact the EMC
expert Robin Segall at