If you are a current cleanroom garment user, the true test is not by testing your garments, it’s by testing your product. Most internal quality assurance departments have all the necessary equipment to test the critical components of their product. A simple pareto analysis of the defects can be very revealing. As an example, I once worked with a company that made glass for critical applications. The glass was manufactured in a white room. Defects that were cause for rejection were: 1) foreign objects embedded in the glass 2) scratches 3) discoloration 4) improper thickness. When performing a pareto analysis of the rejected product, they learned that the number one reason for the rejection was foreign objects embedded in the glass.
Display data in Pareto Chart form for easy analysis
A closer look revealed it was mostly fibers and hairs. Upgrading their garment program from frocks to coveralls and adding bouffants and beard covers dramatically reduced their reject rate. Once the program was in place for a while, a re-evaluation indicated the number 1 cause for rejects was now discoloration. Upgrading the cleanroom garment program to full-face hoods certainly would not have any affect on the discoloration, so there was no reason to change the garment program further.If your product reject rate is low due to particulates and fibers, your garment program is working for you! If you are finding particulates and fibers on or in your product, it’s time to re-evaluate your garment program. Should you wear a different type of garment? Perhaps a different fabric is in order? Maybe your people are not changing garments frequently enough? Start with the simple changes first and measure the affect on your product.