Truncated Domes as a Wayfinding Device

Detectable warnings are often strictly described in their primary purpose; indicating a transition to a vehicular way using truncated domes as a wayfinding device Research has shown that they can also produce additional benefits which include providing a way finding device to the visually impaired, acting as a warning to other specific individuals, and providing additional traction for all users of the pedestrian curb ramp.

Tactile detectable warnings are useful for young children and persons with cognitive disabilities who may not be entirely focused on their pedestrian route and surroundings which invariably could result in entering the vehicular way without due care. The visual and tactile warning at transitions reminds such individuals to be cautious. The truncated domes may also be used as a teaching aid as those when require warnings can be taught to look out for these particular warnings.

One focus involved in developing tactile warning systems is to create a surface which is very slip resistant giving additional traction to pedestrians and wheelchairs on the inclined surface of the ramp. The truncated domes in detectable warnings are aligned in rows parallel with the direction of travel on the ramp facilitating wheelchair travel by allowing the tires to travel between the rows. Without this provision, the domes would become an obstacle requiring increased effort to traverse particularly when combined with the effort required to propel a wheelchair up an incline slope. The inline truncated domes also act as a way finding device for the visually impaired. The alignment of the domes can be sensed with the end of a cane as well as underfoot directing the user across a roadway to the pedestrian walk way on the other side, continuing along their chosen path. For this reason, a sweeping radius curb ramp around an entire corner is not recommended as it does not provide a specific directional cue.

In addition to the truncated domes, specific way finding devices are available to help the visually impaired proceed in a certain direction. These devices take the form of raised a raised line in the pedestrian or vehicular way which users can run a cane along. These systems are used in projects and communities which make full use of all available options regarding accessibility and waypfinding solutions

Bruce Woolner

 

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