In general, engineering quality is classified as 「Good」 and 「Poor」, of which「Poor」 indicating roughly “just” usable, however, engineering quality required by clean room is classified as “usable” and “unusable”. For instance, a clean room was originally required to be class 1,000, while test result was class 10,000, indicating it’s not only「Poor」, but also 「Unusable」. The clean room need very high investment cost as well as high maintenance and running costs, thus, requirements of clean room for engineering quality have to be extremely rigorous.
Construction of clean room must be implemented on the basis of detailed「Construction Plan」, with clear indications of type of materials, list of specifications, construction method, items to be accepted, criteria for acceptance etc, along with practical supervision and construction management, so as to ensure good engineering quality. Any negligence may cause loss against the employer of clean room, and it’s generally more than loss of money. So, it’s inappropriate for the employer to take 「price」 as the only criteria in the selection of contractor. For a contractor who is unable to present a complete construction plan, the employer is likely to suffer loss in most cases!
Further, the employers should preferably to assign an engineer in the trade of clean room engineering, who will supervise and guide execution of the whole project.