This European Standard specifies the single-pole temperature compensated arc fault circuit breakers with or without signal contacts, rated from 3 A to 25 A and used in aircraft on-board circuits. In any operating state a "trip-free" tripping is ensured. These items are designed to protect aircraft wiring system from circuit overload and arc faults. It describes specific environmental, electrical and mechanical characteristics and the stringency of tests to be applied according to test methods of EN 3841-100. If the design of the arc fault circuit breakers contains software or complex hardware, as a minimum, the software and hardware shall be developed in accordance with RTCA DO-178B or C, DAL C and RTCA DO 254, DAL C, respectively. These arc fault circuit breakers are intended for use in aircraft with electrical supplies in accordance with EN 2282.