Airborne particulates range in sizes from 0.001 microns to several hundred microns. A typical High Efficiency Particulate Air (HEPA) filter is rated to filter out 99.97% of 0.3 microns (or larger) particles. For higher grade filters, there are Ultra-Low Penetration Air (ULPA) filters that have a minimum efficiency 99.999% at 0.1 microns.
The key to creating and maintaining a clean environment is based on the principles of:
- Isolating the clean environment to prevent ingress of contaminants from the external environment
- Diluting the air within the environment with clean air to keep the particle concentration low
- Minimizing the generation and accumulation of contaminants within the clean environment itself.
The following tests are performed in accordance with the current edition of NEBB(National Environmental Balancing Bureau) Procedural Standard for Certified Testing of Cleanroom, ISO 14644-3: (2015) and the relevant sections of the Institute of Environmental Science and Technology IEST-RP-CC001.6 (HEPA/ULPA filters), IEST-RP-CC006.3 (Testing Cleanrooms):
- Airborne Particle Count Cleanliness Classification Test
- Airflow Volume/Velocity Test
- General Temperature and Relative Humidity Test
- Air Change Rate
- Light Level Test
- Sound Level Test
- Room Pressurization Test
- HEPA/ULPA Filter Installation Leak Test
- Electrostatic Test
- Bench Scan Filter Leak Test
- Airborne Microbial Sampling Test
And many more…
