Verifying environmental data

Before category 1 and 2 data are added to the National Environmental Database (NMD), the environmental data and the associated Life Cycle Assessment (LCA) file must be verified by a Stichting NMD recognised LCA expert. The aim of the verification is to assess whether the supplied environmental data are formulated in accordance with the Environmental Performance Assessment Method for Construction Works. Data owners (company or sector) may select a recognised LCA expert to verify their product’s environmental data and pay the costs of carrying out the verification.

 Data owners (company or sector) may select a recognised LCA expert to verify their product’s environmental data and pay the costs of carrying out the verification.

Read more about the Assessment method

NMD Verification protocol

All data incorporated in the NMD after 1 January 2020 must be assessed according to the prevailing NMD Verification protocol. If there are changes to the Assessment Method, the NMD Verification protocol will be modified accordingly, which is why the NMD Verification protocol was amended on 1 July 2019. Data verified in accordance with previous versions of the NMD Verification protocol can unfortunately not be included. The Assessment Method can be downloaded below.

NMD Verification Protocol v1.1 -

(Including Verification Protocol July 2020 and amendment Feb 2021)

Data review in the NMD

The data entered in the NMD will only be published after being verified. For category 1 and 2 data, the verification will be carried out by a recognised LCA expert. The LCA practitioner of the data in question will designate experts via the input module. The steps that must be taken to verify and approve the data are described in a manual. Following approval, the data are published automatically in the NMD the next day.

Klik hier voor het downloaden van de handleiding data-review

Register of recognised LCA experts

An LCA expert can be eligible for recognition as independent, qualified third party for verifying LCAs if he or she meets the conditions for recognition. The candidate can apply to Stichting NMD by completing an application form and submitting the necessary supporting documents, in accordance with the recognition conditions. Annual charges are associated with recognition as LCA expert. 

Check the rates

More about recognised LCA-practitioners

Pre-verification for project-specific LCAs

The pre-verification is an initial check on project-specific LCAs (particularly for the civil engineering sector) and safeguards quality of the LCA early on in the process. The review is carried out by a Stichting NMD recognised LCA expert and is based on the Assessment Method principles. Using the pre-verification provides clients and contractors with more certainty over the submitted LCAs during the tender and design phase, without the parties facing high costs at this stage. The pre-verification can be used to check whether the LCA has been formulated professionally and in compliance with the Assessment Method, without a complete verification being carried out. The pre-verification is therefore not a replacement for the verification of environmental data in line with the Verification protocol that should be carried out prior to project delivery and offers no guarantee that the LCA results will not deviate.


As-built verification of project-specific LCAs

The ECI value (Environmental Cost Indicator) is increasingly used for project tenders in the rail and civil engineering sectors. Project-specific Life Cycle Assessments (LCAs) are therefore regularly produced by the contractor to demonstrate a project’s ECI value. In major road-building projects this mainly concerns asphalt and concrete, as well as sheet piling, noise barriers and numerous other products, for which an LCA is produced.

Read more about the As Built Toetsingsprotocol

Review and publication

Assessment of the environmental data to be supplied for inclusion in the NMD must be carried out by an LCA expert recognised by the NMD Foundation. This expert is responsible for completing the assessment tables included in the NMD Assessment Protocol. After entering the data, the LCA performer selects the desired recognised LCA expert in the input application. Then, after checking the report and the data input, the recognised LCA expert gives the green light for publication of the data in the NMD. The data in the NMD are updated every 24 hours.

An exception to this rule is the data from the MRPI Foundation's database. Agreements have been made with them regarding initial testing under the supervision of Stichting MRPI, so that testing for inclusion in the NMD is carried out by employees of Stichting NMD.


NMD Verification Protocol v1.1 -

(Including Verification Protocol July 2020 and amendment Feb 2021)


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