Validators and verifiers

Validators and verifiers approved by the Federal Office for the Environment (FOEN) conduct an independent appraisal of projects and programmes and the emission reductions resulting from them.

Projects and programmes to reduce emissions must be validated by a validator approved by the FOEN at the applicant's own expense (Art. 6 para. 1 CO2 Ordinance). Project monitoring reports must be verified by a verifier approved by the FOEN (Art. 9 para. 2 CO2 Ordinance).

Liste der zugelassenen Validierungs- und Verifizierungsstellen (XLS, 47 kB, 23.04.2020)Art. 6 para. 1 and Art. 9 para. 2 CO2 Ordinance (in German, French or Italian)

The communication on the 'Validation and verification of domestic emission-reduction projects and programmes' sets out in detail how the Administrative Office for Compensation handles the practical implementation of validations and verifications, and serves as a best practice guide for validators and verifiers.

Validierung und Verifizierung von Projekten und Programmen zur Emissionsverminderung im Inland


This publication does not exist in English. It is available in other languages.

Companies interested in obtaining approval as validators and/or verifiers (including re-approval after withdrawal of approval) can apply by email to using the application form below, which sets out the requirements for approval.

Anmeldeformular für Validierungs- und Verifizierungsstellen (DOC, 83 kB, 31.01.2020)Art. 6 para. 1 and Art. 9 para. 2 CO2 Ordinance (in German, French or Italian)

Additional requirements for re-approval

Validators and verifiers who have had their approval withdrawn as a result of the feedback process (see below) should note the following if applying for re-approval:

If the application for re-approval includes experts whose reports contributed to the withdrawal of approval (i.e. who produced inadequate reports that violated the measures agreed for the trial period), those experts must undergo training provided by the FOEN in order for the re-approval to be granted. The FOEN will suggest two or three possible dates for this training.

If the new application does not involve the re-approval of an expert whose reports contributed to the withdrawal of approval, the validator and/or verifier only needs to submit the documents normally required for a first approval.

The training reviews the key framework conditions as well as specific issues arising from the appraisal reports that were deemed inadequate. It is followed by an exam consisting of two parts, a multiple-choice test and an open-response test. The multiple-choice test comprises approximately 20 questions on implementation issues and is (mostly) not specific to a particular type of project. The open-response test covers key areas typically included in validations and verifications. It is tailored to the specific project type(s) for which the validator and/or verifier was approved before the approval was withdrawn and for which it wishes to re-apply. The questions deal with issues typically associated with the project type(s) concerned. For district heating network projects, the questions cover, for example, justifiable reasons for deviating from the reduction paths specified by the Administrative Office for Compensation, checks on the existence of key customers, and the choice of reference where a gas network is present.

Experts who fail the exam will not be approved.

Experts will be approved if they:

  1. meet the requirements set out in the application form AND
  2. either pass the exam or were not asked to sit it.

Feedback process for validators and verifiers

The FOEN assures the quality of validation and verification reports by the following process:

Validierungs- und Verifizierungsstellen Feed-back geben (PDF, 116 kB, 19.01.2018)Art. 6 para. 1 and Art. 9 para. 2 CO2 Ordinance (in German, French or Italian)

Summary and consequences for validators and verifiers

Validators and verifiers receive feedback from the Administrative Office for Compensation on every report they produce. This includes a rating in which the report is assigned to one of the following categories: 'ohne Befund' (very good), 'ausreichend' (good/satisfactory) or 'ungenügend' (inadequate). The number of inadequate reports is counted.

This document sets out to indicate to the validators and verifiers which findings in the reports automatically and in isolation lead to an overall "insufficient" assessment, i.e. even in the absence of further findings. In this way, the Administrative Office for Compensation is supporting the validators and verifiers in setting priorities in the respective reports.

First meeting

If at least three reports have been rated inadequate, the validator and/or verifier is invited to a first meeting at which it has a chance to comment on the ratings. Together with the Administrative Office for Compensation, it agrees on measures to improve the quality of the reports and the timetable for implementing these measures. All reports rated inadequate up to this point are then disregarded (i.e. the counter is reset to zero).

Second meeting

A second meeting is called if, after the agreed time, a further three reports are rated inadequate and violate measures agreed at the first meeting. At this second meeting, the validator and/or verifier has another opportunity to comment on the ratings. Once again, it agrees on measures to improve the quality of the reports, together with the Administrative Office for Compensation. These replace the previous measures. A 'trial period' is also set.

Trial period completed successfully

The trial period lasts a maximum of one year. It starts at the same time as the measures begin to take effect and is ended early if ten reports receive 'ohne Befund' or 'ausreichend' ratings in light of the agreed measures. Once the trial period has been completed successfully, all inadequate ratings and the agreed measures cease to apply and the feedback process starts over again.

Trial period completed unsuccessfully -> approval withdrawn

If the Administrative Office for Compensation rates one of the first ten test reports as 'inadequate', it checks whether any of the agreed measures has been violated. If this is not the case, the trial period continues as normal. The inadequate report will not count towards the ten satisfactory reports needed to end the trial period early. However, if an agreed measure has been violated, the process of withdrawing approval begins. The approval is withdrawn by means of an FOEN ruling.

Once the withdrawal of approval comes into force, the validator and/or verifier is prohibited from taking on new validation or verification contracts. The Administrative Office for Compensation removes the company in question from the list of approved validators and verifiers published online and notifies relevant parties about the change. The validator and/or verifier may complete reports for any contracts that it accepted before the withdrawal of approval came into force.


After the withdrawal of approval has come into force, a new application for approval as a validator and/or verifier may be submitted to the FOEN. 


Agreements with emission-reduction targets must be validated by a validator approved by the FOEN at the applicant's own expense (Art. 12a para. 1 let. a CO2 Ordinance).

Last modification 18.02.2020

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