The UL requirement testing in 6.3.2.1 and 6.3.2.2 apply to the mounting means of equipment having a mass exceeding 7 kg installed in a rack that can be extended away from the rack for installation, service and the like. This requirement does not apply to equipment fixed in place and provided with equipment subassemblies or racks having a top installation position less than 1 m in height from the supporting surface. For the purpose of these requirements, the mechanical mounting means for such equipment will be referred to as slide rails. These requirements are intended to reduce the likelihood of injury by retaining the equipment in a safe position and not allowing the slide rails to buckle, the means of attachment to break, or the equipment to slide past the end of the slide rails. Slide rails shall have end stops that prevent the equipment from unintentionally sliding off the mounting means.