The first clean rooms were created in wartime, say historians. During World War II, American and British industrial manufacturers realized that in order to improve the reliability of the instrumentation used for weapons and tanks, a clean production environment was needed. Some wartime experts say it was during the Manhattan Project, when the first atomic bomb was created, that engineers designed and implemented a basic form of the modern-day, cleanroom HEPA filters, which were used to filter out dust and other pollutants from the production areas. Any area that requires a controlled production or research environment also requires reliable monitoring. Even pest management used in areas around and in cleanrooms must implement methods that will not jeopardize the room’s contamination level. Not only are cleanrooms required to meet international standards regarding the level of air cleanliness and pollutants, they must be constantly monitored to exhibit evidence that those standards are being met.
ISO Compliance ChangesThe International Organization for Standardization (ISO) addresses the classification levels and monitoring requirements of air cleanliness in clean rooms. Those standards were revised in late 2015, increasing the number of samples that must be obtained to monitor compliance. In addition, the number of samples to be collected is determined by a table instead of using an equation as was required in the past. Air cleanliness is now specified through the number of airborne particle concentrations, and does not address airflow patterns.
Environmental MonitoringMaintaining the level of pollutants—aerosol particles, airborne microbes, or chemical vapors—within the room varies with the type of cleanroom required, which requires continual monitoring of the room.
- Cleanroom surfaces—walls, ceilings, floors and equipment—must be cleaned and monitored.
- The air quality inside cleanrooms must be monitored regularly, and include measurements for temperature, humidity levels, and particle counts.
- Not only must the surfaces and air quality in control rooms be monitored, the employees must be monitored as well. Even though workers in cleanroom environments are usually gowned, they carry with them bacteria from everywhere. Gowning procedures must be constantly monitored to ensure effective pollutant control.
- Effective environmental monitoring andcleanroom management depends upon monitoring equipment and instrument accuracy, and the ability of the equipment to provide consistent, repeatable data.