ISO 9647:1989

The method is applicable to vandadium contents between 0,005 % (m/m) and 1,0 % (m/m), provided that the tungsten content in the test portion is not higher than 10 mg and/or the titanium content is not higher than 5 mg. Specifies principle, reagents, apparatus, sampling, procedure, expression of results and test report. The annexes give additional information on the international co-operative tests, a graphical representation of precision data and procedures for the determination of instrumental criteria.