Cleanroom, or no cleanroom is a question to be answered when planning to manufacture a medical device or in-vitro diagnostic. But do you know how to choose whether or not a cleanroom is required? Read here a step-by-step decision help.
Cleanrooms for Medical Devices
If you are not that familiar with cleanrooms, let’s us set the stage on this. Cleanrooms are controled environments, usually by temperature and humidity, whereas the level of particulate contamination is low. There are, in fact, different levels of cleanrooms, depending on the maximum particulate contamination which are stated in ISO 14644-1.
The classes of reduced particulate contamination, and thus, cleanliness, is given in absolute levels satted with integers starting from 9 being not very clean up to 1 being very clean.
| Class | 0.1 um | 0.2 um | 0.3 um | 0.5 um | 1 um | 5 um |
|---|---|---|---|---|---|---|
|
ISO 1 |
10 |
2 |
|
|
|
|
|
ISO 2 |
100 |
24 |
10 |
4 |
|
|
|
ISO 3 |
1’000 |
237 |
102 |
35 |
8 |
|
|
ISO 4 |
10’000 |
23’700 |
1’020 |
352 |
83 |
|
|
ISO 5 |
100’000 |
237’000 |
10’200 |
3’520 |
832 |
29 |
|
ISO 6 |
1’000’000 |
|
102’000 |
35’200 |
8’320 |
293 |
|
ISO 7 |
|
|
|
352’000 |
83’200 |
2’930 |
|
ISO 8 |
|
|
|
3’520’000 |
832’000 |
29’300 |
|
ISO 9 |
|
|
|
35’200’00 |
8’320’000 |
293’000 |
The ISO 14644-1 does not define biological contamination and thus, only particulate contamination is defined. In the consequence, the classification of cleanliness for cleanrooms in the named standard cannot be used for aseptical processing.
Which level of ISO is applicable to me?
As there is no “one fits all” answer to this, it actually is depending on the medical device manufactured in the environment. With the risk-based approach, the cleanliness level for the cleanroom can be determined.
Imagine a medical device, which contact with the patient is via its intact skin. There is thus no need to be super clean during manufacturing. In fact, the risk stemming from a particulate contamination is very low and thus, the manufacturing environment might “only” be free of manufacturing aids and contaminats coming from the processing, such as oils, greases and solvents. In this, case, the ISO 14644-1 might not even be applicable.
In another case, imagine a medical device, which will be implanted into the patient and remains in the human body at a very well vasculated area. The risk from particulate contamination might have devastating impact on the patient’s health. Thus, particulates should be reduced for several reasons, e.g. that particles could enter the blood stream or that bacteria could reside on those particles.
With that said, the clinical risk evolving from the amount of particles and the size of the particles let’s decide on the level of cleanliness.
We just use ISO 7 all the time, right?
As a good starting point, terminally sterilized medical devices can be manufactured in a cleanroom of ISO 7. But this is not all the time true nor a wise guess. The risk evolving from the allowed particles might bear an inacceptable risk to the patient or to the performance of the device.
It might be that parts of the device are prone to failure when particles contaminate it. This can be, e.g., with electronics or sensors.
How Avanti Europe can help
Avanti Europe’s Experts have a decade-long track record and expertise in consulting and hands-on working in process implementation in the Pharmaceutical, Cosmetical, and Medical Device industry. Our experts support your company with hands-on workforce and support in risk-based process design, documentation, and training for the company staff. Visit our online shop for checklists and other services.
