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Reaction to R&R findings
Question regarding R&R findings.
We have recently conducted an R&R on a digital balance that is used in our lab for weighting samples for dissolution to run on XRF. The procedure was developed in the early 80’s and specifies a sample size of 2g +/-.0005g. This sample is then digested and diluted to 100ml. When this procedure was developed, it was concluded that a variance in the sample of .002g was insignificant, in other words the XRF could not repeatedly discriminate. However, in an effort to reduce the amount of variation, the author of the procedure chose to limit the total sample variation to .001g.
The results of the R&R indicate the total R&R is 39% of the total tolerance, (.001g), which is above the allowable 30%.
The question is: Should the procedure be changed to allow a tolerance of +/-.001g for the sample, thus increasing the amount of total variation, but would cut the R&R findings to 19% of the total tolerance?
We are just wondering what direction to take in this matter.
Just for information, our plant is certified QS9000 and the lab is A2LA accredited. Thanks for any replies.
Question regarding R&R findings.
We have recently conducted an R&R on a digital balance that is used in our lab for weighting samples for dissolution to run on XRF. The procedure was developed in the early 80’s and specifies a sample size of 2g +/-.0005g. This sample is then digested and diluted to 100ml. When this procedure was developed, it was concluded that a variance in the sample of .002g was insignificant, in other words the XRF could not repeatedly discriminate. However, in an effort to reduce the amount of variation, the author of the procedure chose to limit the total sample variation to .001g.
The results of the R&R indicate the total R&R is 39% of the total tolerance, (.001g), which is above the allowable 30%.
The question is: Should the procedure be changed to allow a tolerance of +/-.001g for the sample, thus increasing the amount of total variation, but would cut the R&R findings to 19% of the total tolerance?
We are just wondering what direction to take in this matter.
Just for information, our plant is certified QS9000 and the lab is A2LA accredited. Thanks for any replies.