Sch 1A para 1
(a) Electromagnetic environments are classified into classes E1, E2 or E3 as described below, unless otherwise laid down in the appropriate instrument-specific Schedules. This class applies to instruments supplied by the battery of a vehicle. Such instruments shall comply with the requirements of E2 and the following additional requirements: — voltage reductions caused by energising the starter-motor circuits of internal combustion engines, — load dump transients occurring in the event of a discharged battery being disconnected while the engine is running. (b) The following influence quantities shall be considered in relation with electromagnetic environments: — voltage interruptions; — short voltage reductions; — voltage transients on supply lines and/or signal lines; — electrostatic discharges; — radio frequency electromagnetic fields; — conducted radio frequency electromagnetic fields on supply lines and/or signal lines; — surges on supply lines and/or signal lines.