Hi Mohamed, this point is related to a relatively recent amendment to ICAO Annex 6 Part I for CAT aeroplane operators (see Chapter 15, standard 15.1).
You can consult ICAO Doc 10102 'Guidance for Safe Operations Involving Aeroplane Cargo Compartments', first edition 2020. There you have 50 pages of guidelines for how an aircraft operator can ensure safety of cargo compartments of its aircraft.