The starting point of the NMD is to work with as many propriety (category 1) environmental declarations as possible. Besides challenging companies to innovate, proprietary environmental declarations best represent actual environmental impact. 

However, the NMD currently also contains many averages (category 2 and 3) due to a lack of data supplied by manufacturers. 

The ‘database version’ refers to the system version and relates to the system updates behind the data stored in the NMD. The ‘data version’ refers to data updates – adding, editing or deleting data. In the past the data and system version ran in parallel: With the release of NMD2.3, both the data and the system are updated. In the new NMD3.0 system, these two are separated. The data version has been time-dependent since that time. As the data are updated every 24 hours, a new version of the data appears every 24 hours. The system version remains the same.

Stichting NMD manages both the National Environmental Database (NMD) as well as the NMD Process Database. The NMD is a database filled with product cards. This is the database that is used by the calculation tools to produce ECI and EPD calculations. The NMD Process Database is used as source (to draw up LCAs) for the data included in the product cards in the NMD.

The data in the viewer is derived from the product maps in the NMD. Currently, the viewer does not always display the current status of the NMD. This is due to technical problems. We are working hard to solve the problems and make the viewer up-to-date again. The issue is a link between the database and the viewer and therefore has nothing to do with the data in the database. However, the data of published product maps are correctly stored in the database and can also be used in the validated calculation tools.