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Burns suffered in electrical accidents can be very serious. Burns are usually one of three types: electrical burns, arc burns, and thermal contact burns. This topic is concerned with the second type — arc burns.
In its basic terms, an arc flash is a short circuit and air is the conductor. Arc faults are similar to arc welding. Arc burns are the result of high temperatures produced by electric arcs or by explosions close to the body. If the current involved is great enough, these arcs can cause injury or can start a fire. Arc burns are similar to burns and blisters produced by any high temperature source.
Fires can also be created by overheating equipment or by conductors carrying too much current. Extremely high-energy arcs can damage equipment, causing fragmented metal to fly in all directions. In atmospheres which contain explosive gases or vapors or combustible dusts, even low-energy arcs can cause violent explosions.
Scope
Employees working in areas where there are potential electrical hazards shall be provided with, and shall use, electrical protective equipment that is appropriate for the specific parts of the body to be protected and for work to be performed.
Regulatory citations
- 29 CFR 1910.335 — Safeguards for personnel protection
- 29 CFR 1910.137 — Electrical protective equipment
Key definitions
- Conductor:
- Bare. A conductor having no covering or electrical insulation whatsoever.
- Covered. A conductor encased within material of composition or thickness that is not recognized by this subpart as electrical insulation.
- Insulated. A conductor encased within material of composition and thickness that is recognized by this subpart as electrical insulation.
- Energized: Electrically connected to a source of potential difference.
- Exposed: (As applied to live parts.) Capable of being inadvertently touched or approached nearer than a safe distance by a person. It is applied to parts not suitably guarded, isolated, or insulated
Summary of requirements
- Maintain protective equipment in a safe, reliable condition.
- Periodically inspect protective equipment.
- Protect the insulating material if it can be subject to damage during use.
- Require employees to wear nonconductive head protection whenever there is the danger of head injury from electric shock or burns due to contact with exposed energized parts.
- Require employees wear protective eyewear and face protection wherever there is danger of injury to the eyes or face from electric arcs or flashes or from flying objects resulting from electrical explosion.
- Require employees use insulated tools or handling equipment if the tools or handling equipment might make contact with exposed energized conductors or circuit parts.
- Require that fuse handling equipment, insulated for the circuit voltage, is used to remove or install fuses when the fuse terminals are energized.
- Make sure that ropes and handlines used near exposed energized parts are nonconductive.
- Use protective shields, protective barriers, or insulating materials to protect each employee from shock, burns, or other electrically related injuries while that employee is working near exposed energized parts which might be accidentally contacted or where dangerous electric heating or arcing might occur.
- Guard normally enclosed live parts that are exposed for maintenance or repair.
- Require that safety signs, safety symbols, or accident prevention tags are used where necessary to warn employees about electrical hazards.
- Use barricades, in conjunction with safety signs, where it is necessary to prevent or limit employee access to work areas exposing employees to uninsulated energized conductors or circuit parts.
- Station an attendant to worn and protect employees if signs and barricades do not provide sufficient warning and protection from electrical hazards.