• Electrical Safety
• Factors involved in Electrical Shock
• Electrical Safety Reminders

Electrical Safety

To safeguard against injury when using electrical equipment, requirements and standards have been established through the implementation of nationally recognized codes, approval tests and electrical safety work practices.

All electrical equipment must be installed and maintained in accordance with the following standards:

• OHSA Regulations - 29 CFR 1910
• Underwriter Laboratories
• National Fire Protection Association
  (NFPA) 70E, Electrical Safety Requirements for Employee Workplaces

Wiring

All electrical installations or the replacement, modification, repair or rehabilitation of any electrical installation must comply with the requirements of the National Electrical Code (NEC) of the National Fire Protection Association, and/or the U.S. Department of Labors’ Occupational Safety and Health Administration.

For permanent equipment and or permanent wiring contact the Department of Facilities Electrical Services Manager at: http://web.mit.edu/facilities/

Grounding

All equipment should be grounded and fused in accordance with NEC. All extension and power cords must have a grounding pin.

Insulation

All electrical equipment should be properly insulted. Any power cords that are frayed must be discarded and any live/hot wires should be insulated to prevent danger of electrical shock.

National Consensus Standards for Design and Installation

All electrical equipment must be installed and maintained in accordance with the following standards:

• OHSA Regulations - 29 CFR 1910
• Underwriter Laboratories
• National Fire Protection Association
  (NFPA) 70E, Electrical Safety Requirements for Employee Workplaces
• Standards on electrical products and systems, such as the National Electrical Manufacturers Association (NEMA) www.nema.org and ASTM American Society for Testing and Materials. www.astm.org
• Institute of Electrical and Electronic Engineers (IEEE) "Color Book Series" - design of electrical power systems for industrial and commercial facilities
• National Fire Protection Association (NFPA) 70

National Electrical Code (NEC)® -supported by the NFPA provides electrical safety requirements for wiring methods used in the workplace, for live electric supply and communication lines and equipment for employees in the workplace.

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Factors Invovled in Electrical Shock

• THE QUANTITY OF CURRENT FLOWING THROUGH THE BODY
  
  Current (amperes) is the killing factor in electrical shock, not the voltage. The voltage only determines how much current will flow through a given body resistance. In general, the body's resistance to electrical shock is minimal (150,000 to 600,000 Ohms.) Even contact with standard 110-volt circuits can be lethal under certain conditions. Refer to the chart below.
  
• THE CURRENT PATH THROUGH THE BODY FROM ENTRY TO EXIT
  
  Hand-to-hand, hand- or head-to-foot, and ear-to-ear current paths are the most dangerous because they may cause severe damage to the heart, lungs and brain. This is why it is important not to wear metal jewelry, not to lean against or use both hands on electrical equipment so as not to become part of the circuit.
  
• THE LENGTH OF TIME THE BODY IS IN THE CIRCUIT
  
  The longer the body is in the circuit, the greater the damage. You may be unable to let go of a 15 to 20 milliampere current. The body temperature may increase possibly damaging tissues, bones, and organs.

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Electrical Safety Reminders

• Re-route electrical cords or extension cords so they don't run across the aisle/corridor or over pipes or through doors.
• Turn off and unplug equipment before removing the protective cover to clear a jam, replace a part, etc.
• Don't use an electrical outlet or switch if the protective cover is ajar, cracked, or missing.
• use dry hands and stand on a dry surface when using electrical equipment.
• Remove any combustible materials, such as paper and wood from the area. Be sure flammable liquids and gases are secured away from the area when the appliance is in use.
• Never put conductive metal objects into enrgized equipment.
• Remove cord from the outlet by pulling the plug instead of pulling on the cord.
• Don't carry equipment by the cord - only by the handle or base.
• Be sure extension cords are properly rated for the job and used only temporarily.
• Use extension cords with 3-prong plugs to ensure the equipment is grounded. Never remove the grounding post from a 3-prong plug so you can put it into a 2-prong.
• Don't overload extension cords, multi-outlet strips or wall outlets.
• Take seriously any warning signs, barricades or guards posted when electrical equipment is being repaired, installed, etc.

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