A new and useful barrier device for a fluid system cover is provided. The method stores downhole tool data corresponding to a hydrocarbon-bearing sample collected from a given subsurface formation. In another method, the thus obtained parameter value at no less than two different temperatures and the activation energy are used to select proper heating fluids and operating temperature and to determine whether to add an antifoulant to the hydrocarbon stream to reduce fouling at a given temperature. The unit further includes a power unit, having a plurality of sockets, which are adapted to engage one of a plurality of engagement pins or a plurality of recharging pins.