In order to be authorised, an operator must comply with all relevant ICAO standards, unless covered by either a) or b) below:
a) For reasons of equal treatment, EASA will not require compliance with those ICAO standards for which any EASA Member State has filed a difference to ICAO.
b) EASA publishes a list of standards for which mitigating measures may be accepted, provided that the State of the operator had filed a difference to ICAO. In this case, the applicant operator must demonstrate mitigating measures to EASA that provide for an equivalent level of safety to that of the international standard. For all other cases which do not fall under a) or b) the operator needs to demonstrate compliance with the international (ICAO) standard.