Lighting is mostly an afterthought in Cleanroom design, as the overall aim is to reduce contamination. Precision is paramount in cleanrooms. Therefore, to prevent contamination, Cleanroom equipment (including lighting) must be installed by Cleanroom professionals, all the while remaining germ-free.
The highly detailed work conducted in cleanrooms requires different requirements for lighting. Cleanroom lighting depends on its classification, as well as the purpose of the Cleanroom and ceiling air supply configuration. Subsequently, lighting should be designed with cleanability, electromagnetic field generation and contamination control issues in mind.
Cleanroom Lighting Fundamentals
Cost is a major consideration when choosing a lighting system for your cleanroom. Contributing factors include the initial cost and the cost of maintenance. Overheads are not a significant concern, as lighting consumes less than 1% of total energy consumption in the cleanroom.
Hence, the focus shifts to coordination with air supply systems, proper illumination and minimising the contamination of processes conducted within the clean environment.
The level of illumination depends on the different process areas within the cleanroom. Our engineers review all process areas to determine the illumination levels required for the type of tasks performed in the cleanroom.
One complication with lighting placement and spacing is the air supply system. Most of the ceiling in a restrictive Cleanroom consists of air supply filter panels, without any space for recessed lighting fixtures. A good Cleanroom design ensures maximum visual comfort and efficiency to enhance performance in the cleanroom.
Cleanroom Lighting Levels
- Foot candles: A foot candle is the unit of lighting luminance, which equals one lumen per square foot.
- Lumens: Lumens describe the luminous flux or the light output of the source.
- Lux: Interprets how the human eye sees the light and measures the brightness/light intensity.
Common Cleanroom Lighting Fixture Types Offered By Total Clean Air
Recessed Troffers
This fixture is ideal for Cleanroom ISO Class 8 to ISO Class 5, because they have plenty of space in the plenum and ceiling. While rooms with ISO Class 7/8 have more space than ISO Class 6/5, both can incorporate recessed fixtures. Industries include pharmaceuticals, electronic assembly, chemical lab and semiconductor manufacturing.
Surface Mounts
Demanding environments with ISO Class 3 or ISO Class 4 can install surface mount fixtures below the ceiling plane. Usually, there is insufficient plenum space, because of the high air filtration level required. This makes surface mount more efficient than recessed troffers in these situations.
Surface Mount Teardrops
For many years, teardrop light fixtures were the standard in Cleanroom illumination. They are suitable for cleanrooms with an open-area design and an ISO Class 5 or ISO Class 4. The aerodynamic shape minimises disturbance of the laminar airflow into the room from the ceiling air supply.
The primary issue with this fixture was that they reduced the effective headroom in the cleanroom. Most of the available space is allotted to air filters.
