Cleanroom Construction Design Guidelines
| Filtration Classification | Quantities and Percentage of Coverage |
||
| Fed 209E English | Fed 209E Metric | ISO 14644-01 | Recommended Percent of HEPA/ULPA Ceiling Coverage |
| Class 100,000 | M6.5 | Class 8 | 4% diffused air |
| Class 10,000 | M5.5 | Class 7 | 10% recommended diffused air |
| Class 1,000 | M4.5 | Class 6 | 27% recommended laminar flow air |
| Class 100 | M3.5 | Class 5 | 54% laminar flow air |
| Class 10 | M2.5 | Class 4 | 90% laminar flow air |
| Class 1 | M1.5 | Class 3 | 100% laminar flow air |
Ceiling Coverage Calculations
To determine the recommended ceiling coverage required with 2′ x 4′ HEPA’s or ULPA’s divide the square foot of the cleanroom by eight (2′ x 4′) then multiply the recommended percentage and that will provide you with the quantity of units needed.
Note: The recommended quantities are for reference only. They are based on optimum room layout and design to obtain certain class cleanrooms with the minimal amount spent on filtration. The arrangement and spacing of filtration is one of the most crucial characteristics of cleanroom design. Equipment layout, return air grills and personnel have profound impact to the fluid dynamics of the room. Cleanroom protocol and maintenance also are key factors in ensuring constant contamination control to desired specifications.
