While controlled environments must have stringent contamination control protocols, critical cleaning of the product itself is better accomplished outside of the cleanroom. The cleaning process, including washing, rinsing and drying, can itself generate airborne contamination resulting in particle and/or thin film deposition on product surfaces. Where product cleaning within the cleanroom is required, the process must be designed so that most of the mechanical equipment remains outside the controlled environment. The product should be nearly clean enough before it enters the cleanroom. Controlled environments cannot magically correct a contaminated product.

This cleanroom tip was contributed by Barbara Kanegsberg of BFK Solutions LLC, a leading consultant in the design, verification, and improvement of processes for critical product cleaning. 310-349-3614; barbara@bfksolutions.com