As with industrial helmets, bump caps are intended to provide protection against sharp or pointed objects (such as corners or protruding elements of static objects), and so a penetration test is required. The test is based on a method similar to the shock absorption test, in that a striker is dropped from a set height onto the helmet fitted to a fixed headform. However, in this case, the striker is a pointed cone, and rather than measure the transmitted force, the assessment is based on whether the striker makes contact with the headform underneath the helmet. This can be carried out using indicator material (e.g. plasticine or soft metal) on the headform itself, or by establishing electrical contact between the striker and headform (where if the striker contacts the headform, a circuit is complete which sounds an alarm). As with shock absorption, the penetration test in EN 812 is carried out at a lower energy (500 g striker dropped from 500 mm) than that specified in EN 397, to reflect the nature of the hazards. As with the impact testing, this is carried out on helmets pre-conditioned to high temperature, low temperature, water immersion and UV ageing.