2010 ADAS 307.2 – Protruding Object Limits
Objects with leading edges more than 27 inches and not more than 80 inches above the finish floor or ground shall protrude 4 inches maximum horizontally into the circulation path. As an exception, handrails shall be permitted to protrude 4 1/2 inches maximum.
Code according to 2010 ADAS. Check your state’s accessibility laws. Some states such as California, Georgia and Florida have additional requirements and standards.