1. The accessibility requirements referred to in Article 4 shall apply only to the extent that compliance:

(a) does not require a significant change in a product or service that results in the fundamental alteration of its basic nature; and

(b) does not result in the imposition of a disproportionate burden on the economic operators concerned.

2. Economic operators shall carry out an assessment of whether compliance with the accessibility requirements referred to in Article 4 would introduce a fundamental alteration or, based on the relevant criteria set out in Annex VI, impose a disproportionate burden, as provided for in paragraph 1 of this Article.

3. Economic operators shall document the assessment referred to in paragraph 2. Economic operators shall keep all relevant results for a period of five years to be calculated from the last making available of a product on the market or after a service was last provided, as applicable. Upon a request from the market surveillance authorities or from the authorities responsible for checking compliance of services, as applicable, the economic operators shall provide the authorities with a copy of the assessment referred to in paragraph 2.