Critical Dimensions

© 2006 Door & Access Systems
Publish Date: Fall 2006
Author: Rick Sedivy
Page 66

TECHNICAL TIP

Critical Dimensions
For Installing Accessible Communications Entry Systems

By Rick Sedivy, DoorKing, Chair of DASMA’s Operator & Electronics Access Systems Committee

If you install accessible communications entry systems, you must pay close attention to several critical dimensions. Doing so will help your installation comply with industry standards and with ADA (Americans with Disabilities Act) requirements. The tips below explain and illustrate various key dimensions.

ANSI/DASMA 303 defines an accessible communications entry system as “a communications system that allows individuals, including those with physical and/or sensory disabilities, to gain access to a building or facility.” The 303 standard also contains performance requirements for these entry systems.

When mounting the system, you must consider the “clear floor space” needed to allow easy access by a person in a wheelchair. The mounting height must also accommodate the wheelchair-bound and people with restricted movement due to a physical disability.

Approach and Reach

Two primary dimensions of the mounting location are the approach dimension and the reach dimension.

The approach dimension must consider that persons in wheelchairs may approach the unit from the front or from a side-reach point. Mount the unit so that people can approach within three inches (76 mm) of the system without encountering protruding objects or standing within the swing of a door.

The reach dimension involves several factors.

· Unobstructed forward reach. When the clear floor space allows only a forward approach and is unobstructed, the mounting height must be at least 15 inches (381 mm) and no more than 48 inches (1.22 m) above the floor to the controls. See Figure 1.
· Obstructed high forward reach. If the high forward reach is over an obstruction, reach and clearances must be as shown in Figure 2.
· Unobstructed side reach. When a clear floor space allows a parallel approach and the side reach is unobstructed, the mounting height must be at least 15 inches (380 mm) and no more than 54 inches (1.37 m) above the floor to the controls. See Figure 3.
· Obstructed high side reach. If the side reach is over an obstruction, the reach and clearances must be as shown in Figure 4.

The ANSI/DASMA 303 standard seeks to provide expanded accessibility for all. By applying these key installation dimensions, we can all contribute to that important goal.