Last week, a code official contacted me because he had seen some egress doors in a school that were equipped with sensor bars used to release electromagnetic locks. What caught his eye was the signage on the doors, instructing building occupants to remove their gloves before pressing on the bar – assumably because the bars will not work when a person is wearing gloves.
The school is located in a state that is often very cold in the winter, so it is not uncommon for people to put their gloves on before leaving the building. In my opinion, the signage directing people to remove their gloves constitutes “special knowledge or effort,” since people would need to read the sign and follow the instructions before they are able to exit (the code official agreed with this interpretation).
There’s another problem with this application when used in a school. The model codes require doors to be equipped with panic hardware when they are serving assembly or educational occupancies with more than 50 people (IBC) or more than 100 people (NFPA 101). If a door is not equipped with a lock or latch (if it has push/pull hardware only), panic hardware is not required. But if the door has any sort of a lock or latch – including a mag-lock, it has to have panic hardware.
Although there is panic hardware available that can incorporate a switch to release a mag-lock, sensor bars that do not latch are not typically listed as panic hardware. Panic hardware must be listed to the UL 305 standard; if a sensor bar is not listed to UL 305, it is not panic hardware and is not allowed to be used to release a mag-lock on a door that is required to have panic hardware – unless the AHJ allows it.
If you need more information about electromagnetic locks and the code requirements that apply to these applications, there is a Decoded article here. For more information about panic hardware, there is a Decoded article here, and a whiteboard animation video here.