Safeopedia Explains Electrical Safety
OSHA Electrical Safety
The Occupational Safety and Health Administration (OSHA) has a number of standards related to electrical hazards.
OSHA’s general industry electrical safety standards are published in Title 29 of the Code of Federal Regulations (CFR):
- Design Safety Standards for Electrical Systems – Part 1910.302 to 1910.308
- Electrical Safety-Related Work Practices Standards – Part 1910.331 to 1910.335
Electrical safety standards for other industries include:
- Construction – 29 CFR 1926, Subpart K
- Marine terminals – 29 CFR 1917
- Longshoring – 29 CFR 1918
- Shipyard standards – 29 CFR 1915
OSHA is not the only agency that publishes safety standards. Other standards of note include:
Dangers Associated with Electricity
Electricity will always attempt to travel to the ground by following the path of least resistance. And when the human body comes into contact with electricity, it often becomes that path of least resistance.
Any current above 50 mA has the ability to disrupt the body’s respiratory response and cause death. For comparison, static shocks are generally no more than 2 mA, whereas a police taser is no more than 4 mA. Most human bodies will seize up between 10 mA and 30 mA. Extreme pain sets in between 31 mA and 150 mA. Nerve damage and a possible fatal outcome occurs between 151 mA and 4,300 mA. Severe burns and cardiac arrest result from contact with any current beyond that.
Contact with electricity can cause:
- Electric shock, which is an injury that occurs when a part of the body comes into contact with electricity and becomes part of the circuit
- Thermal burns, which result of the body converting electricity to heat
- Electrocution, which is any contact with electricity that results in a fatality
Arc Flash
One of the most dangerous electrical hazards is arc flash. An arc flash is a discharge of intense heat and light that happens when a fault develops in an electrical circuit. The arc gets progressively hotter, reducing the electrical resistance and drawing more current until some part of the system trips, melts, or evaporates.
Arc flashes are extremely brief events, but can nevertheless cause serious harm. The risks associated with arc flash events include:
- Deafening noise that can result in hearing damage
- High energy radiation
- Arc blast (a supersonic shockwave)
- Shrapnel
- Extremely high temperatures that can cause severe burns
The Five Golden Rules of Electrical Safety in the Workplace
The Five Golden Rules of Electrical Safety are basic guidelines for anyone working on electrical equipment. Following these significantly reduces the risk of electric shock and other electrical injuries.
The Five Golden Rules are:
- Disconnect: Unplug the equipment before doing any work on it, or turn off the circuit breaker
- Prevent Reconnection: Fully lockout the equipment and notify all surrounding personnel (following LOTO procedures) to ensure that no one will plug it back in, flip the circuit breaker back on, or otherwise reactivate it
- Check for Voltage: Check the equipment to make sure that there is no voltage remaining
- Ground the Equipment: Ensure that the equipment is properly grounded to prevent an accidental discharge of electricity
- Mark Off the Area: Post signs or demarcate the area to discourage untrained and unauthorized personnel from going near the equipment
Electrical Hazard Recognition
Electrical incidents are more likely to happen when workers are unaware of the dangers, overlook an electrical hazard, or have not been trained in handling electrical equipment correctly.
Below are some key electrical hazards that workers should be trained to recognize.
Damaged Insulation
Electrical wires are typically covered with insulating material. Insulating materials do not conduct electricity and, as such, can be touched and handled without the risk of a shock or other injury.
However, this insulation can suffer wear and tear, deteriorate over time, or become damaged. Even small amounts of damage to the insulation leaves the wires exposed and can deliver a shock to anyone who makes contact with them.
Occasionally, employees will attempt to fix wires using glue, tape, or by splicing other cords together to complete the circuit. These can all lead to damaged insulation and create a hazardous situation.
All employees should be trained on how to inspect cords and other wires for damage and understand the risk of handling non-insulated or augmented wiring.
Improper Grounding
A grounded electrical system is one that is connected to a grounding point (i.e., clipped to conductive metals that are attached to the ground in some fashion). Grounding allows the electrical current to flow into the earth, where it can safely dissipate. This creates a safe pathway for the current instead of coursing through a worker’s body and delivering an electrical shock.
Grounding is a simple and effective safety measure; however, it can’t be taken for granted by those who work on or around grounded equipment. Rough treatment or extreme environmental conditions can compromise the grounding – and the protection it provides.
Contact with Power Overhead Power Lines
As electrical hazards go, overhead power lines might be the most obvious. We all know that power lines are electrical hazards and that contact with them can be dangerous and deadly. Yet, workers often put themselves at risk around power lines without realizing they’re doing so.
Even when workers don’t come into direct contact with power lines, they should still understand the risks and how to avoid them.
Any elevated equipment, such as boom lifts, should be kept at least 10 feet away from power lines at all times. If possible, power lines should be de-energized. Anyone working near them should also use tools and ladders made of non-conductive materials.
Improper Use of Extension Cords
Extension cords are incredibly convenient and useful, but they can also suffer a lot of wear and damage.
Extension cords can become loose as a result of frequent use. The ground prong can bend or break off, compromising the safety of the cord. The insulation can also become damaged over time, exposing the wiring and putting workers at risk of shock.
Not all extension cords are built equal, and workers should be trained on the different types and their uses. That includes understanding the difference between cords meant for general use (marked with an “S”) and those rated for outdoor use (marked with a “W”). Knowing how to verify that an extension cord has been approved by an independent testing laboratory is also essential.
Note that extension cords are not designed to be permanent wiring, nor are they permitted to be used as such according to OSHA guidelines. Extension cords are not to be spliced together, daisy chained, or used through windows or doorways.
Damp Conditions
Water conducts electricity, which means damp conditions will heighten the risks when working with electrical equipment.
Using electrified equipment with wet hands can significantly increase the risk of electric shock. Equipment designed only for indoor use might not be safe to use outdoors in the rain.
Electrical Safety Tips
The following general safety tips will help protect employees who are exposed to electrical hazards.
Assess Electrical Hazards Before Working
When working in a remote location or in an unfamiliar setting, perform a brief inspection of the surroundings to identify potential electrical risks. Take steps to control the hazards before doing any work. If there is no way for you to implement adequate controls, notify your supervisor and do not start working until it is safe to do so.
Avoid Contact with Electrical Wires
Avoid touching electrical wires without safety gloves, even if the wires are insulated.
Never Deal with Electricity When Wet
Water on the floor, on your hands, or dampness in the working area can significantly heighten the risk and severity of an electrical shock. Take steps to dry your hands, the floor, and anything wet or damp before working. If it is raining, you may need to wait until the weather is more favorable and the area has dried.
Leave the Repairs to Qualified Personnel
Only qualified and authorized personnel should repair electrical wiring or devices. Even if it seems like a simple repair task, do not attempt it unless you have received the proper training or certification.
Make Sure Electrical Equipment Is Properly Grounded
Grounding gives electrical currents another path to go through, rather than passing through your body. Before working on, with, or near electrified equipment, verify that it has been grounded properly and that the grounding area is free of impurities, such as rust.
Follow Lockout / Tagout Procedures
When doing maintenance on energized equipment, turning it off isn’t always enough. Locking out the device will prevent it from being activated unexpectedly.
Follow your employer’s lockout / tagout procedures when doing maintenance work. This will ensure that the device is locked, can’t accidentally release energy, and won’t be turned on or reactivated before the work is done.
Electrical Safety Training
Like all workplace hazards, mitigating electrical safety risks will require a number of different controls. Personal protective equipment (PPE), regular maintenance of electrical systems, warning signs, and insulated tools can all play a role in keeping workers safe.
One of the most important steps to preventing electrical incidents, however, is ensuring that all employees have received adequate training. Training equips workers with the knowledge they need to recognize electrical hazards, protect themselves from those hazards, and determine whether it’s safe to work.
OSHA’s Electrical Safety Training Requirements
OSHA has established training requirements for employees and qualified professionals to ensure that they can work safely with electricity.
Employers must provide all employees who may be exposed to electrical hazards on the job with electrical safety training. This training must cover, among other things, the basic principles of electrical safety, safe work practices, which tools are safe to use with electrical equipment, and emergency procedures in the event of an electrical incident.
Qualified personnel require more advanced training. This will include knowledge of electrical systems, how to select and use the right PPE for the job, and lockout / tagout procedures.
Ready to learn more? Check out our free webinar on How to Build an Arc Flash PPE Program Your Workers Will Embrace!
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