Rubber for drinking water contact: Why global approvals are important
Clean drinking water is not a matter of course. One thing is to provide the necessary amount of water, another is to ensure the quality of the water. Drinking water quality not only depends on the raw water and the treatment thereof, but just as much on the pipes, fittings, valves, etc. that the water comes into contact with before reaching the consumer.
Based on our extensive know-how, AVK GUMMI contributes to ensuring that the water is not contaminated by the rubber components that we deliver to our customers. An important aspect is that we make sure that the rubber compounds have the required approvals, the purpose of which is to protect the consumers.
As a manufacturer of equipment for the drinking water industry, you are most likely already familiar with the many different regulations – and the fact that the regulations vary between countries and regions to a greater or lesser extent.
Some rubber approvals are required by law, others are recommended, although almost always interpreted as de facto requirements within the country. For convenience, they are all covered under the term Compliance.
When defining your market strategy, you must consider many different aspects, and we will not attempt to judge what is right for your product. However, when it comes to the rubber component, we can help you optimise your market position with the right compliance strategy.
In order for a rubber compound to be approved for drinking water contact, two overall strategies must be considered: One compound for all markets or several market specific compounds. It would seem obvious to choose the first strategy in order to keep your product programme as simple as possible. However, several independent rubber solutions may offer better properties and greater resilience in the market.
Approvals and properties often conflict with one another
An approval is often based on several requirement elements – a so-called approval regime.
There will be either a positive list of approved ingredients or a negative list of ingredients that the final product will be tested up against. In both scenarios, the purpose is to ensure that the consumer is not exposed to ingredients to such an extent that this would be considedered as harmful to human health. In addition, there will be a complex of migration tests, taste and odour, discolouring and others.
The shorter the list of permitted ingredients, the greater are the limitations of formulating a compound with good properties. If several approvals are combined – and with that positive lists – the list of permitted ingredients will be reduced automatically, because the positive lists vary from country to country.
Approvals and resilience
If you have to choose between one global compound and several market specific compounds, it is important to bear in mind that approvals are never static. In most cases, the approvals must be updated on a regular basis, and each time an approval is up for renewal, the latest applicable regulation will apply.
This may present a risk that an approval cannot be renewed – either because a positive list, a method or certain limit values have been changed. This is only seldom the case, but if a compound is approved in 10 different locations, the risk will be increased equivalently. It may be argued that a customer in Germany may be completely indifferent as to whether or not an approval fails in the US. Therefore, there will be very little understanding of the fact that he will have to spend time and resources on qualifying a new compound, only because the regulations in the US have changed.
An alternative would be to have different compounds for the German and the US market respectively. This will of course make your supply chain more complex, but it is an option that you have – that is if you have a supplier who will give you the possibility of making this choice.