Quality Product Audit
Ben Osburn
11 Posts
Hey Guys,

Does anyone have recommendations about how often product audits should be done? I'm thinking it should be based on the frequency of product return. Thanks!
5 Replies
Duke Okes
125 Posts
Product return is certainly one consideration, since it let's you know (with some uncertainty) how often defective product is being shipped.  However, you might also want to consider 1) the ability of a product audit to detect the problem (inspection is not 100% effective), 2) the cost of product audits, 3) the cost and potential customer loss impact when defective product escapes, and 4) other risk considerations.
Duke makes great points.  But if you want this to truly be an audit, it can be treated as such.   You can create a schedule and then sample products across different strata.   The product audit sample can be selected across different product lines, different customers, different manufacturing processes, shifts, etc.
Ben Osburn
11 Posts
Thanks guys. We really only do product audits when there are returns now, but the problem is we get multiple returns for the same products sometimes. I'm thinking maybe the threshold for the audit should be returns per quarter. If we get multiple returns per quarter on one product, we should audit that product on a monthly basis.  
Duke Okes
125 Posts
So you may want to consider doing some pre-shipment audits, and/or some process audits that focus on the controls that have failed to prevent the defects in returned products.
My default answer is that all supplier monitoring, including product audits, should be performed at a frequency determined by risk-based thinking.  You need to consider things like the criticality of the product (is there an effect on human safety?), the severity of an escape, the likelihood of a quality issue, the detectability of those issues, as well as historical performance of your supplier.  If you have data that one or more failure modes tend to occur with some frequency, you might decide to migrate your attention from detection to prevention.  Depending on the failure modes in question, there are several options.  In my company, repeat or critical to quality characteristics often switch on reporting requirements of the supplier.  Those characteristics are required by contract to be inspected and reported by the supplier.  If failures continue to occur, engage the supplier and work through what is now clearly an inspection challenge.

Hope this all helps.  The question was pretty general, so I may have gone down entirely the wrong rabbit hole for you.  Remember that product audits don't need to review all characteristics, just those deemed CTQ or that show repeat failures.  Good luck!