ICAO Annex 14 regulation, for marked structures (painted with white / red horizontal bands), prescribes the use of Aircraft Warning Lights with night-time operation only.
Appendix 6-3 of the standard indicates the use of medium intensity steady burning red (MIOL-C 2.000cd) beacons. For structure identification by AWL, at all levels, medium intensity Type C beacons must be used.
For example, for a structure with a total height of 90 meters MIOL-C beacons must be installed both on top and on the second (and last) level; or, for a building with a height of 110 meters i twill be necessary to use 4 levels: all with MIOL-C lights.
Finally, if an aeronautical study or the civil aviation body under which the control of the structure in question falls, decides the use of other lights or other configurations, the prescriptions must be respected by way of derogation from the ICAO standard Annex 14.