Commercial Building Inspector B2Public Safety and Special ConstructionEasy
A newly constructed three-story office building requires an accessible route from the public way to all accessible building entrances. Which of the following conditions would necessitate the inclusion of a ramp as part of this accessible route?
- AA change in elevation greater than 30 inches (762 mm).
- BA change in elevation of 1/2 inch (12.7 mm) or less.
- CA change in elevation greater than 6 inches (152 mm) but not exceeding 30 inches (762 mm).
- DA change in elevation greater than 1/2 inch (12.7 mm) but not exceeding 6 inches (152 mm).
Show answer & explanationAnswer & explanation
Correct answer: D. A change in elevation greater than 1/2 inch (12.7 mm) but not exceeding 6 inches (152 mm).
According to IBC 1003.5 and ADAAG 4.8.1, a ramp is required for changes in elevation greater than 1/2 inch (12.7 mm). Changes in elevation of 1/2 inch or less are typically handled by beveled surfaces.
Why the other options are wrong
- A. Changes greater than 30 inches would require multiple ramp segments or an elevator, but the necessity starts much earlier.
- B. Changes of 1/2 inch or less can often be accommodated by beveled or flush surfaces without a ramp.
- C. While a ramp can cover this range, the necessity for a ramp begins at 1/2 inch, not 6 inches.
Ramp Requirement Threshold
A ramp is required as part of an accessible route when the change in elevation exceeds 1/2 inch (12.7 mm), as per accessibility standards.
- Accessible routes must connect all accessible building entrances to public ways.
- Changes in elevation over 1/2 inch necessitate a ramp or elevator.
- Beveled surfaces can accommodate smaller changes in elevation.
Memory trick: Half an inch high, a ramp you must apply.