Isolated barriers use galvanic isolation to protect electrical signals in potentially flammable or other hazardous areas. They do not stop signals or communication from getting through—a barrier only stops dangerous levels of current and voltage. Signals are still transmitted between the field device and the control system. However, by limiting the energy to low levels incapable of causing ignition, dangerous sparks cannot form. This intrinsically safe setup prevents electrical shocks, fires, and explosions. The kinds of control and instrumentation signals that isolated barriers can work with include NAMUR sensors, transmitters, valves, solenoids, thermocouples, and other similar IS rated devices.