subject: Cleanroom Certification: What You Need to Know [print this page] Cleanroom Certification: What You Need to Know
A cleanroom is a highly purified area in which the air quality, temperature and humidity are kept under strict control. The air inside a cleanroom is filtered repeatedly to remove dust particles and other contaminants. Cleanrooms are mainly used for manufacturing equipment that is sensitive to contamination, such as microprocessors, silicon chips, hard disk drives and integrated circuits. Cleanroom certification includes examining the room for various parameters, such as temperature, airborne particles, relative humidity, static electricity and differential pressure.
The examination is carried out to ensure that the room is built in compliance with stated standards. Cleanrooms are certified according to standards that are set for the particle content of the cleanroom atmosphere, as measured in PPM (parts per million), temperature controls and the filtration system types. The US standards of cleanroom environments is described in Federal Standard 209E 100,000. The International Organization for Standardization describes standards of a cleanroom air quality in document ISO 14644-1.
Cleanroom Certification: HEPA Filter Installation Leak Test
Cleanroom certification is done by clean room performance testing companies. These inspection and testing firms are certified by the National Environmental Balancing Bureau (NEBB). These companies are equipped with advanced and calibrated instruments required for performing Cleanroom Performance Testing (CPT).
The cleanroom certification testing process includes several tests, some are mandatory while others are optional. One of the most important mandatory tests is:
HEPA Filter Installation Leak Test: HEPA filters are highly effective particle air filters, used to control pollutants and microbes and maintain environmental standards. The minimum efficiency shown by a HEPA filter when tested with an aerosol is 99.97%.
The HEPA installation filter leak test is conducted to detect faults, damage and leaks in the filters. The test also confirms the integrity of the filters and whether they have been installed properly.
The two types of leak tests available for HEPA filters are:
* Total leak test
* Scan leak test
The scan leak test is described in IEST-RP-CC034.1 and the total leak test is described in Section 10 of the ASME N510-1989. For radioactive purposes, only the total leak test is permitted. However, for all other applications, either of the tests can be performed. Both tests require qualification of the testing equipment to ensure consistent results.
Other tests involved in cleanroom certification are the Air Flow, Volume, Velocity, Uniformity, Airborne Particle Count, Room Pressurization, Temperature and Relative Humidity, Visual Airflow Characterization, Light Level, Noise Level and Vibration Level Tests.
