The Institute of Caster and Wheel Manufacturers (ICWM) is comprised of companies that design and manufacture casters and wheels. The load ratings/capacities for casters and wheels are determined through a series of endurance tests designed by the ICWM. This test standard is now an ANSI Standard (ANSI-ICWM-2018).
Because caster load capacities are primarily determined through endurance testing, safety factors are not published, nor generally provided, for caster or wheel products. There are a few exceptions. For more details, please speak with a member of the Northwest Caster team.
Following are short descriptions of the three major ICWM endurance tests: