The Metta impact categories

The impact categories included in the assessment of companies are:

  1. The use of resources, water and energy;
  2. Use of space: quantitatively (area) and qualitatively (landscape aesthetics), buildings, but also landuse for the production of resources;
  3. Greenhouse gases and other emissions to the atmosphere;
  4. Waste: liquid and solid; and,
  5. Noise and light pollution, and possible other sources.


For each of these impact categories, the footprint of a company or organisation is determined for a defined period in the past. This is reflected by the blue line in the diagram below. In most cases, part of that footprint can still be avoided, reduced, restored or mitigated within the firm itself with relatively little effort or investments. For instance, in hte case of energy savings or waste recycling. The situation that occurs if those options are exhausted is reflected by the red line in the diagram. Such reductions in impact lead to cost savings and efficiency increments in many instances.

The impacts contained, or covered by the area within the red line needs to be compensated externally. When that compensation has been commissioned, the company or organisation can communicate to the outside world that it has been impact neutral over that specific period in the past, and it may use the Metta certificate that will state the defined period of time that it covers.


The assessment does take into consideration all efforts that the company or organisation already undertakes to compensate for some of the impacts, such as for instance the use of clean energy.