ENR 1.3 INSTRUMENT FLIGHT RULES

1 In instrument meteorological conditions pilots shall operate in accordance with the instrument flight rules except that within a control zone, a special VFR flight may be authorised.
2 Flights shall be conducted in accordance with the Instrument Flight Rules (even when not operating in instrument meteorological conditions) when operated:

  1. More than 185km (100NM) seaward from the shoreline within controlled airspace; or

  2. During the hours between sunset and sunrise; or

  3. Above FL200.