I part of a community group consulting on a library building with residential accommodation above the library. The library has a basement room with DDA compliant lift and stair access, however the fire exit on the ground floor does not have direct external access. Is this acceptable?

I note: Disabled people should not use any part of a building where it would be difficult for them, even with help, to escape in the event of fire. Use of basements by wheelchair users, where there is no basement level exit, is likely to be an example of this. Activities which might take place in such areas should be moved to different areas, so far as reasonably practicable, to avoid excluding disabled people.
Grateful for your advice

DDA cover far more than wheelchairs but I assume we are discussing wheelchair access. If wheelchairs do not have direct external access/egress then how do they get into the building?