88.1 The prescriptions that apply to an event are the prescriptions of the national authority with which the organizing authority is associated under rule 89.1. However, if boats will pass through the waters of more than one national authority while racing, the sailing instructions shall identify the prescriptions that will apply and when they will apply .

88.2 The sailing instructions may change a prescription. However, a national authority may restrict changes to its prescriptions with a prescription to this rule, provided the ISAF approves its application to do so. The restricted prescriptions shall not be changed by the sailing instructions.