I'm curious as to what type of barricade should be put up when establishing a Limited Approach Boundary or Arc Flash Boundary. Generally tape or rope is used to identify the boundary of the hazard but has there been any decision on what category it falls under? When developing an Electrical Safety Program, should the decision be made to require a red tape (danger) instead of yellow (caution)? OSHA says that danger signs indicate immediate danger (arc/shock hazard) and that special precautions are necessary (PPE). It also goes on to say that caution signs shall be used only to warn against potential hazards. Since no unqualified people are not allowed in these areas without the proper PPE, I would think that a danger sign instead of a caution is warranted.

What are other facilities using to indicate their arc flash/limited approach boundaries?

Signs generally follow the ANSI standards. You can't equate barricade tape standards directly with signage...they are not compatible. So what you are saying would be correct for signage but not necessarily tape "barricades". Also MSHA treats the term "barricade" differently...it means physical access is prevented (guarding). All tapes are just warnings to them.

Generally red tape would be used where some specific action has to be taken to avoid injury or where injury is imminent. For instance danger tape would be placed around the limited approach boundary because either the personnel involved need special training and PPE or require an escort. Yellow tape just warns of a possible hazard that may not be obvious. For instance, "Caution -- overhead work" or "crime scene".

Based on these requirements though it would depend on location. Within a utility substation, all personnel are trained. Thus only warnings would be required (yellow tape). In an industrial plant with mostly unqualified personnel, red tape would be required.

We have to remember that neither NFPA 70E or CSA Z462 indicate that there must be some form of physical barrier to indicate the "Limited Approach Boundary" Whether it be a tape line, rope, etc. I often suggest that what ever method is convenient and appropriate to the electrical worker. Any plant electrician that I have worked with is not exactly carrying around a roll of caution tape or rope line in their tool pouch. Another item is that something that indicates and is communicated to other workers that the electrical worker is in control of that workspace as long as work is being performed. Other considerations could be pylons. Another consideration could be there are magnetic mount portable indicator lights that could easily mount on an enclosure. They are small enough that they could be easily transported in a tool pouch. When the light is on or flashing, this is an indication that electrical work is being done and for workers to stay back at a minimum working distance. Of course this method would have to be communicated to all employees and incorporated into the electrical safety program. Hope that this is of some help