A brief history of cleanrooms
By Sheila Galatowitsch
Cleanroom historians say the concept of contamination control originated as early as the mid-19th century in hospital operating rooms. Modern cleanrooms, however, were born out of the need for precision manufacturing in clean environments during World War II and the subsequent race to space.
During World War II, industrial manufacturers in the U.S. and U.K. developed the first cleanrooms to improve the quality and reliability of instrumentation used in guns, tanks and aircraft, according to W. Whyte in his 1991 book Cleanroom Design. “It was realized that the cleanliness of the production environment had to be improved or such items as bomb sights and precision bearings would malfunction,” Whyte wrote.
Although historians do not pinpoint a date, most agree that the high-efficiency particulate air (HEPA) filter was developed during World War II and became available for industrial use in the early 1950s. Laminar flow technology was formulated in 1961 by a team of Sandia Laboratories researchers led by Willis Whitfield.
One historian writing in the mid 1960s claimed that predecessors of modern-day cleanrooms go back to World War I. Philip Austin in his 1965 book, Design and Operation of Clean Rooms, described “controlled areas within factories or laboratories in which an attempt was made to eliminate the gross contamination associated with manufacturing areas. This contamination, consisting of heavy dust-laden air, had caused seizure of small bearings and gears used in the first aircraft instruments. As a result, controlled assembly areas were built.”
According to Austin, contamination control was first effected by good housekeeping practices, by segregating the work area from other manufacturing operations, and by providing a filtered air supply. With the advent of World War II, better filtration systems were developed, and air conditioning and room pressurization were considered essential. Personnel protective clothing was added later, as were air showers and personnel cleaning equipment.
But the principles of contamination control may go back even further, suggests international contamination control expert Dr. Åke Möller. Many centuries ago, Chinese laquerwork painters created their own version of a laminar air flow bench to produce high quality laquerwork. They used the cleanest possible surrounding, Moller says, sailing out to sea with djonks to perform the work. — SG