I agree with Sidney - the ICOP scheme is ahead of the game when it comes to customer complaints regarding certified companies.
In the automotive industry it's not quite as direct, but can still be effective. Many of the automotive company Customer Specific Requirements (CSRs) require their suppliers to notify their CB if they are put on special containment. The CB is then required to raise a major nonconformity against the supplier's system that must be addressed with certain timing requirements. One of the companies that I audit is going through this process right now.
In the automotive industry it's not quite as direct, but can still be effective. Many of the automotive company Customer Specific Requirements (CSRs) require their suppliers to notify their CB if they are put on special containment. The CB is then required to raise a major nonconformity against the supplier's system that must be addressed with certain timing requirements. One of the companies that I audit is going through this process right now.
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