A safe, indoor trapping device for trapping and killing flying insects can be used in areas containing food, containing animals, for food preparation, etc. A voltage source is used to vary the polarity and, optionally, the magnitude of voltage applied to the terminals in order to control bi-directional flow of electrons within the long conductor layer and, thereby formation of opens andor shorts at the long conductor layer-short conductor layer interfaces. Of a DC bus bar group Including the positive electrode bus bar and the negative electrode bus bar, and an AC bus bar group including the plurality of AC bus bars, part of one of the bus bar groups is sealed with insulating resin, and the other of the bus bar groups is not sealed with insulating resin. The coefficients are normalized and converted into a fly height measurement. In response to receiving a request, a PSAP local to a wireless communications device of a user who sent an emergency data message may be identified, and a network address associated with the identified local PSAP may be provided.