How do you actually know your cleanroom is working the way it should? Well, technically you find out on the day it gets certified.
But what about every day after that?
Cleanroom monitoring systems exist for this exact purpose.
In this article, we’ll define what they are, what conditions they usually track, and what to think about when planning one for your cleanroom.
What Are Cleanroom Monitoring Systems?
Cleanroom monitoring systems are essentially just a network of different sensors and software that track various environmental conditions within a cleanroom. Depending on how you set them up, they can monitor anything from particle counts to temperature, humidity, air pressure, and much more.
In short, they help you confirm (and monitor) that your cleanroom is doing what it’s supposed to.
Also, with these systems in place, you can find out when something goes wrong almost immediately.
What Conditions Are Monitored?
What exactly gets monitored will depend on your industry, sometimes your ISO classification, as well as the regulations you have to follow. The most common variables that are tracked are:
Particle Counts. With cleanrooms this is the most basic measurement. Laser particle counters can detect suspended particles at sizes of 0.5 µm and above.
Temperature and Humidity. Most cleanrooms need to stay within a defined range, usually around 18°C to 22°C and 30% to 60% relative humidity. If either drifts too far, it can potentially affect the products/processes inside.
Differential Pressure. The pressure between cleanroom zones needs to stay steady so that air flows in the right direction. If pressure abruptly changes this could create contamination risks, as unfiltered air could begin flowing the wrong way.
Air Velocity. This matters most often in unidirectional airflow cleanrooms, where the speed of the air is what keeps particles from settling in certain places.
Monitoring systems may also track things like door status and CO2 levels, and equipment alarms.
Continuous vs. Periodic Monitoring
Regarding monitoring, there are generally two approaches, but a lot of cleanrooms end up using both.
Continuous monitoring means sensors are installed permanently and feed data into a central system around the clock. If something goes out of range, the system alerts you immediately.
This is standard practice in the pharmaceutical industry, especially in the stricter areas where aseptic processing takes place.
Periodic monitoring means measurements are taken at set intervals, either manually or with portable instruments. This is more common in less strict environments, like ISO 7 or ISO 8 cleanrooms used for electronics or general manufacturing.
The industry as a whole is moving toward continuous monitoring, and it makes sense when you think about it. A periodic reading only tells you what conditions were like at that moment.
Continuous monitoring shows you what’s happening all the time, and more importantly, it catches things as they develop rather than after something has already gone wrong.
What All This Means for Your Cleanroom Design
It’s worth mentioning that monitoring is a requirement in most industries. ISO 14644-2 requires a documented monitoring plan, and FDA 21 CFR Part 11 has its own rules around electronic records and data integrity.
In other words, monitoring directly ties into how the cleanroom is designed and built. Sensors need to go where they’ll gather useful data, which usually means near vulnerable work areas and at other representative points throughout the room.
All of this needs to be planned during the design phase. Power outlets, data ports, conduit pathways for wiring, and wall penetrations for sensor cables all need to be accounted for before the walls ever go up.
If you wait until the cleanroom is already built, you end up with a messier installation and potentially compromise the room’s integrity in the process.
