Verify accessible parking spaces and their access aisles won't exceed the 1:48 maximum slope after a mill-and-overlay or restripe on an unevenly graded lot.

Steps

1. Pull the current 502.3/502.4/502.5 text from access-board.gov/ada/chapter/ch05 or ada.gov/law-and-regs/design-standards/2010-stds.
2. Confirm 502.3 governs the Access Aisle itself (60-inch minimum width, full-length adjoining the space, and striping to discourage parking in it) — it is not the slope provision.
3. Confirm 502.4 (Floor or Ground Surfaces) is the slope provision: access aisles must be nearly level in all directions, with a 1:48 (~2.08%) maximum slope, to support a safe wheelchair transfer surface.
4. Confirm 502.5 (Vertical Clearance) is a separate requirement — 98 inches minimum — for van spaces, access aisles, and the vehicular route serving them; do not label 502.5 as the Access Aisle or slope section.
5. Survey/measure the existing grade of proposed accessible stalls and aisles in all directions, not just running slope, and compare to the 1:48 threshold.
6. If grade exceeds the threshold, flag the space for regrading before restriping, since paint alone cannot cure a slope violation.