What is the allowable reach range for an obstructed side reach over a kitchen counter?

According to the 2010 ADA Standards for Accessible Design, the allowable range for a side reach is defined by a minimum and a maximum height. The low side reach must be at least 15 inches [381 mm] above the finished floor. For an obstructed high side reach, the maximum height is 48 inches [1219 mm] if the obstruction depth is 10 inches or less. This maximum is reduced to 46 inches [1168 mm] if the obstruction depth is between 10 and 24 inches, which is typical for a kitchen counter.

However, since the question asks for the general "allowable reach range" and an obstruction could be less than 10 inches deep, the range of 15" to 48" represents the full scope of possibilities.

A. The 34" [914 mm] dimension is the maximum height for an accessible counter, not the minimum reach range from the floor.

C. The 18" [457 mm] minimum is incorrect; the established minimum low side reach is 15 inches [381 mm] above the floor.

1. U.S. Department of Justice. (2010). 2010 ADA Standards for Accessible Design. Section 308.3

Side Reach.

308.3.1 Unobstructed. "...low side reach shall be 15 inches (380 mm) minimum above the finish floor or ground."

308.3.2 Obstructed High Side Reach. "Where the reach depth is 10 inches (255 mm) maximum

the high side reach shall be 48 inches (1220 mm) maximum."

2. International Code Council. (2017). ICC A117.1-2017 Accessible and Usable Buildings and Facilities. Section 308.3

Side Reach.

308.3.1 Unobstructed Side Reach. "The high side reach shall be 48 inches (1220 mm) maximum and the low side reach shall be 15 inches (380 mm) minimum above the floor or ground."

308.3.2 Obstructed High Side Reach. This section mirrors the ADA standard

specifying a 48-inch maximum reach over an obstruction up to 10 inches deep.

3. Steinfeld

E.

& Maisel

J. L. (2012). Universal Design: Creating Inclusive Environments. John Wiley & Sons. Chapter 7: Anthropometry and Biomechanics

Reach Limitations

p. 254. (This academic text discusses the anthropometric data and research that form the basis for the reach range standards codified in the ADA and ICC A117.1).