Cleanroom Teesing validated: no measurable particles

Our cleanroom, like many other high-tech companies, is the beating heart of Teesing. We produce serial assemblies for systems for gases and liquids, and from a quality point of view it is very important to us that the cleanroom is tested regularly. We are proud that no particles were measured - making our ISO 4 cleanroom actually an ISO 2 cleanroom. And thus we are ready for a future in which our customers will become even more critical of the cleanliness of the systems we supply.

How special is that?

The biggest polluter in a cleanroom is humans. Particles are released from clothing and skin. The cleanliness we need can be compared to a grain of rice in an Olympic-sized pool. If you want to improve then you have to look for that one grain of rice.

Ideally you wouldn't have people present in a clean room, but since that's just not possible, cleanliness is completely dependent on:

• Having smart procedures for assembly and behavior.
• Strict adherence to those procedures.
• Good technical installation.

The number of particles dispersed by humans is enormous. To get an idea of magnitude take a look at the table on the right.

Table: human contamination in a cleanroom per minute presence, for 3 different sizes of particles.

And what are the requirements then?

A person in cleanroom clothing disperses 100,000 particles of 0.5um per minute. In an ISO 4 cleanroom, of those 100,000, only 352 may remain. And that's just from 1 person. There are still some reservations to be made about this reasoning, but it does indicate the enormous technical and human effort it takes to make a cleanroom comply with ISO 4. The table below shows the maximum allowed value for the number of solid particles and how many particles were measured in our cleanroom.

In addition to the number of particles, a whole range of other values are also measured, such as recovery time: how quickly is the cleanroom able to get a contamination back to the required value? On that measurement, too, our cleanroom scores extremely well. All measured values taken together, our cleanroom complies with ISO 2 and we are quite proud of that!