Abstract: An apparatus has a sensor with an electrically conductive ground member, electrically conductive first and second parts spaced from and proximate to each other and the ground member, and an insulator disposed between the ground member and the first and second parts. A different configuration involves a tag having circuitry, and a sensor supported on the tag and having electrically conductive first and second parts that are spaced from and proximate to each other, the first and second parts each being electrically coupled to the circuitry.

Abstract: A support includes a base having an outwardly extending projection with a passageway therethrough, and having a tag receiving portion configured to removably support a tag on the base adjacent one end of the passageway. A different arrangement involves a tag that includes a housing having an opening therethrough and having an annular surface around the opening, an annular gasket engaging the annular surface, and circuitry within the housing having a sensor located in the region of the opening and having a transmitter that can transmit wireless signals. A method includes defining a passageway that provides fluid communication between an interior and exterior of a container, supporting a tag on the exterior of the container, and causing the tag to sense, at a location in the region of an end of the passageway, a condition within the container.