A vapor sensor adapted to detect alcoholic residue at a skin site, the vapor sensor comprising: a housing, wherein the housing comprises an inlet opening extending to the interior of the housing; a sensor element adapted to measure alcohol vapor said sensor element disposed within the housing and in fluid communication with the inlet opening, wherein the sensor element comprises a first conductive member, a second conductive member, and an absorptive dielectric material sandwiched between the first conductive member and the second conductive member; at least one standoff member (140b-d) disposed proximate to the housing, wherein the at least one standoff member is positioned to maintain a gap between the inlet opening and the skin site and the at least one standoff member comprises a tube having a proximal opening, a wall, and a distal opening opposite the proximal opening, the proximal opening contacts the housing and encircles the inlet opening, and the wall has one or more notches and/or one or more holes (144, 148) proximate the distal opening to allow ambient atmosphere adjacent to the skin site to be drawn through the wall into the inlet opening by a fan; an operating circuit in electrical communication with the sensor element and adapted to detect a parameter of the sensor element, wherein the parameter correlates with alcohol concentration; and at least one output member communicatively coupled to the operating circuit, wherein the at least one output member is adapted to generate an output indicative to an operator regarding concentration of alcoholic vapor in the ambient atmosphere proximate the skin site upon receiving communication from the operating circuit. a housing, wherein the housing comprises an inlet opening extending to the interior of the housing; a sensor element adapted to measure alcohol vapor said sensor element disposed within the housing and in fluid communication with the inlet opening, wherein the sensor element comprises a first conductive member, a second conductive member, and an absorptive dielectric material sandwiched between the first conductive member and the second conductive member; at least one standoff member (140b-d) disposed proximate to the housing, wherein the at least one standoff member is positioned to maintain a gap between the inlet opening and the skin site and the at least one standoff member comprises a tube having a proximal opening, a wall, and a distal opening opposite the proximal opening, the proximal opening contacts the housing and encircles the inlet opening, and the wall has one or more notches and/or one or more holes (144, 148) proximate the distal opening to allow ambient atmosphere adjacent to the skin site to be drawn through the wall into the inlet opening by a fan; an operating circuit in electrical communication with the sensor element and adapted to detect a parameter of the sensor element, wherein the parameter correlates with alcohol concentration; and at least one output member communicatively coupled to the operating circuit, wherein the at least one output member is adapted to generate an output indicative to an operator regarding concentration of alcoholic vapor in the ambient atmosphere proximate the skin site upon receiving communication from the operating circuit.