What is MID?
Measuring Instruments Directive (MID) is part of the European CE-marking system and applies for certain regulated measuring instruments, including water and heat meters.
Products and manufacturing processes must comply with the requirements of EU Directive 2014/32/EU, which governs legal metrology across Europe.
For customers, it provides confidence that measurements used for billing and regulatory purposes are accurate and reliable.
In short, MID ensures correct and fair billing.
Scope of the renewal audit
The renewal was granted following an independent audit conducted by notified body LNE.
The audit covered the manufacturing quality system of water meters and heat meters at the following sites:
- Apolda (Germany)
- Ansbach (Germany)
- Saint-Louis (France)
- Bażanowice (Poland)
- Jinan (China)
The assessment focused on manufacturing activities, quality management, testing processes, traceability and product release procedures.
It verified that Diehl Metering continues to operate an effective quality system in line with European requirements.
The independent MID audit confirms compliance with quality system requirements.
Key strengths identified during the audit
Several strengths were recognized during the assessment.
- Manufacturing expertise: Diehl Metering benefits from extensive experience in the production of water and heat meters. This expertise supports consistent quality across all manufacturing sites.
- Accredited laboratories: Our ISO 17025 accredited laboratories support ongoing measurement accuracy.
- End-to-End traceability: Traceability is managed through our MES database, allowing products and processes to be monitored throughout the manufacturing lifecycle.
- Measurement equipment management: Dedicated systems ensure that measuring equipment is properly maintained, calibrated and monitored.
- Cross-Site metrology controls: Regular laboratory comparisons between sites help maintain consistency across our global manufacturing network.
- Integrated Management System: Our IMS framework supports governance, documentation, process control and continuous improvement.
Together, these elements strengthen our manufacturing quality system and support long-term metrology compliance.
Why this matters for utilities and energy providers
For utilities, compliance is not optional. Metering solutions must meet both regulatory and operational requirements.
This renewal confirms that Diehl Metering continues to manufacture meters for legal metrology under independently audited processes.
The quality assurance system provides:
- products meet regulatory requirements;
- measurements remain reliable;
- manufacturing processes are controlled and traceable;
- equipment is suitable for regulated markets.
As a result, MID compliance supports reliable billing and regulatory acceptance across regulated markets outside the European Union.
More than a product type approval
A common misconception is that MID only evaluates product type. In reality, the quality system of the manufacturer must also comply with the regulation and must be audited by a notified body.
Auditors assess quality management, documentation, competence, governance, traceability and continuous improvement practices.
This broader approach helps ensure that compliance is built into everyday operations.
At Diehl Metering, MID requirements are embedded into design, manufacturing, testing and release activities. This supports consistent product quality and reduces operational risk.
Supporting long-term customer confidence
Externally audited conformity systems play an important role in supplier selection, especially for long-term projects and framework agreements. It also confirms our ability to manage complex regulatory requirements across multiple manufacturing sites. We only have one common externally audited system for all sites across the world.
For customers and partners, this means greater confidence in the reliability and compliance of our metering solutions. And provides assurance that our products are manufactured under controlled and audited conditions.
FAQ
Who carried out the audit?
- The audit was conducted by notified body LNE, an independent organization accredited to assess MID compliance.
What products are covered?
- The certification covers the manufacturing quality system of water meters and heat meters.
How long is the certificate valid?
- The renewed quality system certificate is valid for three years.
Why is MID compliance important?
- It allows the manufacture to place the CE-mark with Metrology enhancement. Only these meters are allowed to be used for billing in the European Union.
What is a MID quality system?
- The European conformity assessment framework (Decision No 768/2008/EC) gives several modules (A-H) according to evaluate the product compliance. For measuring instruments for legal billing, it is obligatory to have a CE type approval (module B) and an external audited production quality assurance (module D).
- The MID module D quality assurance system assesses the manufacturer's ability to consistently produce compliant measuring instruments through controlled and audited processes.
What does this renewal demonstrate?
- It confirms that Diehl Metering maintains robust quality, traceability and compliance processes across its manufacturing operations.