Permitting back belts to be used as PPE means that employers must provide them to workers at no cost, if they choose to provide them. The standard allows employers to use PPE to supplement other controls (engineering, work practice, administrative), but PPE cannot be used alone if other controls are feasible.
Wrist splints, wrist braces, and back braces are post-injury devices used to speed rehabilitation, according to OSHA, and are not considered PPE under the ergo rule.