25.4. If the project manager is not present on the date agreed for tests, the contractor may, unless otherwise instructed by the project manager, proceed with the tests, which shall be deemed to have been made in the project manager's presence. The contractor shall immediately send duly certified copies of the test results to the project manager, who shall, if it has not attended the test, be bound by the test results. 

25.5. When components and materials have passed the above-mentioned tests, the project manager shall notify the contractor or endorse the contractor's certificate to that effect. 

25.6. If the project manager and the contractor disagree on the test results, each shall give a statement of its views to the other within 15 days of such disagreement arises. The project manager or the contractor may require such tests to be repeated on the same terms and conditions or, if either party so requests, by an expert selected by common consent. All test reports shall be submitted to the project manager, who shall communicate the results of these tests without delay to the contractor. The results of retesting shall be conclusive. The cost of retesting shall be borne by the party whose views are proved wrong by the retesting. 

25.7. In the performance of their duties, the project manager and any person authorised by him shall not disclose to unauthorised persons information concerning the undertaking's methods of manufacture and operation obtained through inspection and testing. 

## Article 26 - General principles 

## PAYMENTS 

26.1. Payments shall be made in euro or national currency as specified in the special conditions. The special conditions shall lay down the administrative or technical conditions governing payments of pre-financing and final payments made in accordance with the general conditions. 

26.2. Payments due by the contracting authority shall be made to the bank account mentioned on the financial identification form completed by the contractor. The same form, annexed to the invoice, must be used to report changes of bank account. 

26.3. Pre-financing payment shall be made within 30 days from the date on which an admissible invoice is registered by the contracting authority. The invoice shall not be admissible if one or more essential requirements are not met. Final payment shall be made within 60 days from the date on which an invoice is registered by the contracting authority, together with the request for provisional acceptance as per article 31.2. The date of payment shall be the date on which the paying account is debited. 

26.4. The period referred to in article 26.3 may be suspended by notifying the contractor that the invoice cannot be fulfilled because the sum is not due, because appropriate substantiating documents have not been provided or because there is evidence that the expenditure might not be eligible. In the latter case, an inspection may be carried out on the spot for the purpose of further checks. The contractor shall provide clarifications, modifications or further information within 30 days of being asked to do so. The payment period shall continue to run from the date on which a properly drawn-up invoice is registered. 

