If you’ve been reading iDigHardware for a while, you know how much I love to receive questions that I haven’t thought about before (my excitement is a little embarrassing, actually). Last week, I received a question about low-energy automatic operators and the need for them to be actuated by a “knowing act.” There is a lot of information in the article I wrote for Doors & Hardware on this topic, but last week’s question was this:
If a low-energy operator is actuated by a motion sensor, it has to meet the requirements of A156.10 instead of A156.19, which usually means the door must have guide rails and safety sensors. What about the “wave-to-open” switches…are these considered motion sensors?
These actuators may be designated “touchless,” “hands-free,” or a similar term in the manufacturers’ catalogs, but the A156.19 standard calls them “fixed non-contact switches.” These switches are one of the methods defined by BHMA as a knowing act:
2.1 Knowing Act: Consciously initiating the powered opening of a low-energy door using acceptable methods including: wall or jamb-mounted contact switches such as push plates; fixed non-contact switches; the action of manual opening (pushing or pulling) a door; and controlled access devices such as keypads, card readers, and keyswitches.
A156.19 goes on to describe the acceptable range for actuation of these switches (great job BHMA!):
Fixed non-contact switches should have a detection range no greater than 12 in. (305mm) to ensure a knowing act is utilized to activate the door.
In summary, touchless switches for automatic operators are considered a knowing act, but the detection range (the distance from the waving hand to the switch) should be no more than 12 inches. Another hardware mystery solved!