Where the purchaser formulates a technical specification by reference to a standard or an equivalent document, he may not reject a tender on the grounds that it does not comply with that standard or document if the tenderer proves, by any appropriate means, that the solutions he proposes satisfy in an equivalent manner the requirements defined by that standard or document.
Where the purchaser formulates a technical specification in terms of performance or functional requirements, he may not reject a tender if it complies with a standard or equivalent document corresponding to these performance or functional requirements. The tenderer shall prove, by any appropriate means, that this standard or equivalent document corresponds to the performance or functional requirements defined by the purchaser.