Element-by-Element Safe Harbor. The rule includes a general "safe harbor" under which elements in covered facilities that were built or altered in compliance with the 1991 Standards would not be required to be brought into compliance with the 2010 Standards until the elements were subject to a planned alteration. A similar safe harbor applies to elements associated with the "path of travel" to an altered area.
An example: the 1991 Standards allow a 54 inch maximum for the side reach range to a paper towel dispenser lever. The 2010 Standards state the side reach range is 48 inches maximum. If the dispenser was installed prior to the 2012 ADA update,it does not need to be lowered.
with the highest operating part at 54 inches, the paper towel dispenser does not need to be lowered to 48 inches. Since the dispenser complies with the 1991 Standards, that Standard provides a "safe harbor."