Abstract: A two wheel roller caster (10) for use in supporting movable objects on a floor having a conductive band (56) which has two ends and is mounted between two wheels (16) so as to provide conductive contact between the movable object and the floor. A conductive path (60, 58, 56) connects a stem (14) to the connective band (56).

Abstract: A transport vehicle for enabling a user to wheel one or more sensitive electronic components such as circuit board modules from one location to another without subjecting the components to electrical field damage. The transport vehicle is in the nature of a cart formed from a conductive tubular framework supported on wheels. Slidably received between a pair of parallel frame members is a bin formed from a material which has an outer conductive layer forming a Faraday shield and an inner conductive layer or, alternatively, a static dissipative conductive layer which offers a slow, more controlled bleed of static electricity.

Abstract: A control system for diverting/equalizing electrical potentials between two objects, for example the shell (1) of a storage tank installation and the body (10) of a tank truck/vessel, when loading flammable/explosive fluids, wherein an electrical equalizer connection (5,6,14) connects the body (10) of the tank truck via a terminal (10a) to the storage tank (1) via a terminal (1a). The terminals (1a and 10a) are part of respective control circuits comprising a low voltage source (U.sub.1 ; U.sub.2), a resistor (4; 13) and an indicator (8,9) for registering current flow and thereby controlling/blocking the connection/disconnection of a fluid pump. To check that electrical connection has in fact been established at the terminals (1a,10a), each of these is connected to a respective control circuit via separate terminals, namely a terminal (1b; 10b) on the respective bodies (1; 10) and a terminal (6a; 6b) on a busbar (6) in the equalizer connection ( 5,6,14).