Charpy pendulum impact tester is used to conduct resilience tests on rigid plastic materials in order to determine their impact fragility characteristics under standard stress conditions. The test method conforms to ISO 179 – Part 1 (non-instrumented impact test). The sample, supported near its ends as a horizontal beam, is impacted by a single blow of a striker, with the line of impact midway between the supports, and bent at a high, nominally constant, velocity.