OSHA Rebar Safety caps
To address the danger of protruding rebar and to comply with the Standard set by the U.S. Occupational Safety and Health Administration (OSHA), rebar covers also called rebar caps, have become commonplace on modern construction sites.
In accordance with the Standard set by OSHA, rebar covers (rebar caps) should be used so that bars are guarded to eliminate the hazard of impalement. It's important to note however, that not all rebar covers are designed to provide protection from impalement. Cases have been documented where the force of a fall has pushed the rebar clear through a plastic cap to impale a worker, or where a worker was impaled by the rebar and the cap together.
To avoid this type of horrific and life-threatening mishap, only rebar covers designed to provide impalement protection, such as those containing steel reinforcement, are recommended.