1. When is an impact test appropriate? An impact test is appropriate for equipment likely to be used in areas with non-restricted access and where impacts are likely to occur. For equipment destined for areas with restricted access, an impact test may be appropriate but is likely to be of a lower severity. 2. Choice of test apparatus The part of IEC60068 provides three test method which, as far as is practicable, are intended to give similar results. To obtain repeatable and reproducible results, this test is more dependent on the details of the test apparatus than is usual in IEC60068 standards. The choice of the test apparatus depends on the orientation of the surface to be tested and on the energy level. Not all methods can be used in every case. It is self-evident that a pendulum hammer can only be used on vertical surface without overhangings. Similarly, the vertical hammer can normally only be used on accessible horizontal surfaces. When the specimen ca...