In the (potable) water sector, KIWA certification is a widely used standard to guarantee the materials used, for the wet parts of a flowmeter, meet the KIWA standard. After all, these parts come into contact with potable water and must of course comply with certain safety aspects.

Is KIWA certification always necessary for the application in question, or is a potable water certification for these materials also sufficient?

Often the last one, because there is a lot of misunderstanding about the content of KIWA certification.

So what does a KIWA certification entail? The certification consist of two parts: toxic tests on the wet parts and a metrological assessment (measurement accuracy). The flowmeter must meet these two conditions. In the water sector, people are often unaware of this metrological assessment and think a KIWA certificate only contains a toxicological test.

With the toxicological assessment, one tests whether no harmful substances from contact materials get into the potable water and whether, on the contrary, no components disappear from the water into the contact materials. For the metrological assessment, the flowmeter must be calibrated to specific capacities, to ensure a certain measurement accuracy (these are the so-called Qn values).

The most important condition is, the flowmeter should not be accessible to change the settings (including those that do not affect the measurement of the flowmeter). This is done by sealing the flow meter, as done with flowmeters for billing (e.g. the water meter at your home).

If all conditions are met, the meter can be provided with a KIWA watermark sticker.

However very often flowmeters are not used for billing, but used as process flowmeters. In this case, settings will sometimes have to be changed, for example due to changes in the process (such as the measuring range to the PLC system). This is not possible if one has a KIWA certified flowmeter; namely, you have a sealed meter. In such a situation, the toxicological part would be sufficient. But KIWA does not have a separate toxicological certification.

However, KROHNE is fully KIWA certified according to the latest standard.

Our consultants will be happy to visit you to discuss your measurement challenges.