In this credit, there is a requirement for an STCc 50 rating for "Office, conference room" to "Hallway, stairs". This description (“hallway, stairs”) is rather ambiguous, as it could mean an adjacent (but non-associated) corridor/hallway or the hallway through which these rooms are accessed. In the latter case, the STCc 50 rating would not make any sense for a typical office project, as the door into the room from that same hallway/corridor would typically only achieve STC 35 in most cases and thus prevent the STCc 50 rating from being achieved, unless extraordinarily expensive STC rated doors and constructions were used. This would not be a reasonable mitigation option for offices to implement. Sufficient speech privacy can still be achieved with a standard office or conference room door and masking without this substantial expense (with all due apologies to the sound rated door manufacturers).

Ultimately, I am wondering whether the description "Hallway, stairs" can be interpreted as the hallway/stairs being an adjacent (but non-associated) space, not the space from which the office or conference room entry door is shared.  This would be a more reasonable interpretation of this credit.

Thank you for any feedback or suggestions of how this should be interpreted.