Tenn. Code Ann. § 55-10-424: "Transdermal monitoring device" defined

As used in this part, "transdermal monitoring device" means any device or instrument that is attached to the person, designed to automatically test the alcohol or drug content in a person by contact with the person's skin at least once per one-half (1/2) hour regardless of the person's location, and which detects the presence of alcohol or drugs and tampering, obstructing, or removing the device.