Blocking refers to the protection of information both from people who do not have a need-to-know for the information being discussed and from illegal intelligence activities.
The soundproofing requirement applies only to those premises in the area where classified information is discussed. The sound insulation can be evaluated, for example, by listening to the conversation outside the premises near the doors, walls, air conditioning pipes and other openings. If necessary, the sound insulation of the space can also be compared to the airborne sound insulation requirement for structures.
If necessary, the sound insulation requirement can be achieved, for example, by repositioning the space, improving the insulation of structures and penetrations, or background noise from spaces outside the evaluated space.
