A clean room must be kept under strict control, including airborne contaminants, temperature, relative humidity, air pressure, electrostatics and so forth according to the product manufactured in the clean room and the clean room classification for operation according to specific standards.
In spite of best efforts to control and prevent contamination from reaching critical product surfaces, products still become contaminated through airborne particle fallout, particle migration mechanisms, human interactions, and other means.
Clean room environments vary widely from one facility to another. As direct comparisons between are difficult to make, benchmarking the process environment in clean rooms provides important baseline information to identify opportunities to improve performance and cleanliness.
The Contamination Assessment is a key element in the overall Contamination Control Program. It establishes the baseline and standard for the program against which all subsequent assessments are measured, and to gauge whether parameters have or have not changed.
The Assessment focus' on the facility, product, processes, cleanroom operations, personnel protocols, garments, and disciplines, contamination types (particle, microbial, chemical, radiation), equipment, materials, testing, specifications, airflows, particle transport mechanisms, cleaning systems, and electrostatics to determine the etiology of contaminants that will adversely affect product yield or performance. A combination of air quality and airborne particle fallout assessments are used to determine areas of contamination concern where product and critical processes are subject to contamination. Best practices are established ensure applicable contamination control procedures are adopted to address any detrimental conditions that will affect product reliability, quality, or cost. Measures and methods, such as Localized Process Control, are specified to prevent contamination from reaching sensitive surfaces.
Utilized in the assessment process are Airborne Particle Monitoring and Particle Fallout Monitoring. These tools are used to determine the levels of contamination affecting critical product and process areas.
