Table 6.26 – Wheelchair Space Overlap in Assembly Areas
Current Guidelines:  
4.3.3  Width.  The minimum clear width of an accessible route shall be 36 in (915 mm) except at doors (see 4.13.5 and 4.13.6). . . .

Final Revised Guidelines:  
402.1  General.  Accessible routes shall comply with 402.

402.2  Components.  Accessible routes shall consist of one or more of the following components: walking surfaces with a running slope not steeper than 1:20, doorways, ramps, curb ramps excluding the flared sides, elevators, and platform lifts.  All components of an accessible route shall comply with the applicable requirements of Chapter 4.

403.5.1  Clear Width.  Except as provided in 403.5.2 and 403.5.3, the clear width of walking surfaces shall be 36 inches (915 mm) minimum. . . .

802.1.4  Approach.  Wheelchair spaces shall adjoin accessible routes.  Accessible routes shall not overlap  wheelchair spaces.

802.1.5  Overlap.  Wheelchair spaces shall not overlap circulation paths.

Model Codes & Standards
IBC 2000:  Section 1008.7.6 prohibits obstructions in the required width of assembly aisles, except for handrails. 

IBC 2003:  Section 1024.9.6 prohibits obstructions in the required width of assembly aisles, except for handrails.