In mechanics, an impact is a high force or shock applied over a short time period when two or more bodies collide.
Impact tests are used in studying the toughness of material. A material's toughness is a factor in its ability to absorb energy during deformation. Brittle materials have low toughness as a result of the small amount of deformation that they can endure. The impact value of a material can also change with temperature. Generally, at lower temperatures the impact energy of a material is decreased.
We test our luminaires with the aid of a pendulum of known mass and length that is dropped from a known height to impact a specimen. The specimen is placed in a specialized chamber with temperatures down to -50°C. The temperature in the chamber should be five degrees lower than the lowest ambient temperature (Ta value) specified by the manufacturer for the luminaire being tested.