The colour coding system is part of the numerous regulations that the lifting operations industry has put in place to manage the use of different equipment. The regulations require that suitable marks are placed on the lifting equipment for safety purposes. One should know the safe working load limit to reduce the risk of injury they are exposed to. The sling cannot lift any load that is more than the working load limit. Different colour codes are used to indicate the limits of lifting slings. http://www.herunsling.com/textile-sling/