One of the questions that comes up often under the Drinking Water Directive is: “When do I actually need to call my Notified Body if I make a change?” Manufacturers don’t want to be reporting every tiny update, but they also don’t want to risk non-compliance by keeping silent about something important. The answer lies in the distinction between changes to your quality management system (QMS) and changes to your product.
Changes in Your Quality Management System (QMS)
In a Module D certification — and also in the DWD under Module B certification — you have an ongoing obligation to operate an approved quality system. Such a system must be resistant to change and ensure continuous compliance. You are also subject to yearly surveillance audits on site, which means Notified Bodies already check that your system evolves in a controlled way.
Because of this, you do not need to contact your Notified Body every single time something changes - otherwise, you would be calling them every day to report a new form template or a new hire on the production line. Instead, the rule of thumb is: only inform Notified Bodies if the change could affect the scope or reliability of your certification related to the production of the already approved product.
Examples where you must inform the Notified Body include:
Integration of new production techniques not previously audited.
Overhauling a significant part of your production or monitoring process.
Introducing a new factory or production site.
Major changes to your QMS that affect compliance with the regulation.
Changes outside the certified scope, such as new product types.
In some cases, this may trigger a new on-site audit. In other cases, submitting updated documentation may be enough to close the concern. As part of your QMS, you are expected to have a procedure assigning responsibility for deciding when the Notified Body must be informed. This decision must be based on a risk assessment, and in some cases the obligation will be explicitly written into your certification agreement.
Changes in Your Product
When it comes to your actual product, the rule is much stricter. The DWD system is type-based: your Module B certificate covers a product type that was tested and approved. Any significant change to the product that could affect its conformity — formulation, composition, suppliers, production method, or design — needs to be reported to the Notified Body before you place the modified product on the market.
For example:
A new formulation or alternative supplier not already covered by certification.
Switching from injection moulding to extrusion.
Adding a new material or component not included in the approved design.
Extending production to new product types or categories outside the scope of your certificate.
These changes usually require either additional testing, an extension of the Module B certificate, or in some cases a new audit to confirm compliance. Unlike QMS tweaks, product changes cannot simply be managed internally — they have to be cleared through the conformity assessment system.
Generally speaking thus under DWD, almost all changes to the product itself - will require informing of the Notified Body.
The Bottom Line
QMS changes: Only notify the Notified Body if the change significantly affects compliance or scope (new sites, new techniques, major system changes). Minor adjustments stay under your own responsibility, and will be reviewed at the next surveillance audit.
Product changes: Always notify the Notified Body if the change could alter conformity. The Module B certificate only covers the tested and approved design, and placing a modified product on the market without approval risks non-compliance.
In other words, your quality system must manage daily evolution internally, while product changes must be escalated. If in doubt, a short call to your Notified Body is better than risking a product recall later.
We can also support in this regard to make risk based decisions on when to be on the safe side and what changes are acceptable.