Electrical Safety – You’re Doing It Wrong
Ok I’ll admit it, I chose that title because I wanted to get your attention. But in my experience (and in my defense), a lot of companies don’t understand what OSHA requires when it comes to electrical safety. So let’s talk OSHA, and more specifically their electrical requirements.
Why Care?
Electricity is a wonderful thing. We use it to power our homes, machines, tools, lighting, medical equipment… the list could go on forever. Electricity is also a frightening thing. Coming into contact with an electrical circuit can lead to shock (whether minor or severe), electrocution (shock leading to death), arc flash, arc blast, and burns. Electrical energy remains one of the most serious hazards in the workplace, yet accidents are often avoidable. Electrical accidents are typically caused by either unsafe conditions, such as poorly maintained equipment, loose connections, or insulation failure, or by unsafe work practices, such as not de-energizing prior to work or using conductive tools. Often, it’s a combination of both.
Breakdown of the Standard
To avoid boring you with numerous regulation references, I’ll give you a quick overview of OSHA’s electrical safety standard. There are two electrical standards, one for General Industry (29 CFR 1910, Subpart S) and one for Construction (29 CFR 1926, Subpart K). Given the consistency between both standards, I’ll focus on Subpart S. OSHA’s Electrical standard is broken down into 4 divisions:
- Design Safety Standards (1910.302-.308)
- Safety-Related Work Practices (1910.331-.335)
- Safety-Related Maintenance Requirements (1910.361-.380)
- Safety Requirements for Special Equipment (1910.381-.398)
Be sure to remember the names of the first two divisions. I mention them quite a bit in this article and they are discussed in detail below.
What Applies to Me?
One of the first questions to ask yourself is whether or not you are covered under the electrical safety requirements. Chances are if you have electrical equipment, at least some of OSHA’s electrical requirements are going to apply to you. Although there are exceptions, the design safety requirements cover all electrical equipment used in buildings, on structures, on your premises, or on other premises (if the equipment is your responsibility).
The safety-related work practice requirements cover all of your employees, whether qualified or unqualified, if they face a risk of electric shock above 50 volts. If employees face a risk of shock, OSHA requires them to be trained and familiar with certain parts of the standard.
Design Safety Requirements
To start, let’s focus on equipment safety (which in turn helps keep employees safe). A lot of information is contained in this set of requirements, 1910.302-.308. The highlights are provided below – and yes, believe it or not, it’s a very condensed version!
OSHA requires the following:
- Electric equipment must be examined to ensure it is free from serious recognized hazards. Employers should consider equipment insulation, heating effects, arcing effects, wire bending, mechanical strength, listing/labeling (by a nationally recognized testing laboratory), and classification.
- Electric equipment must be installed according to its listing/labeling instructions (by a nationally recognized testing laboratory).
- Electric equipment must be located away from damp or wet areas, including areas with gases, fumes, vapors or liquids, unless specifically rated for that location.
- Circuit breakers and switchboards located in wet areas must be enclosed in weatherproof enclosures.
- Openings in electrical boxes, cabinets, panels, etc. must be closed up (not with tape or paper).
- Internal parts of equipment must not be contaminated with paint, cleaners, or corrosives.
- Electric equipment must be firmly secured to the surface on which it’s mounted.
- Electric equipment must be marked with the manufacturer’s name or trademark, and the system voltage, current, wattage, or other markings.
- Disconnect switches, circuit breakers, or other overcurrent devices must be marked to identify their purpose when it’s not readily obvious.
- Disconnect switches must be capable of being locked out (according to lockout/tagout).
- For equipment 600 volts or less, at least 36-inches of clearance must be provided in front of the equipment.
- Panel doors or hinged panels must be able to open at least 90 degrees.
- The minimum headroom above the equipment, starting from the floor, should total no less than 6.5 feet. So it’s important not to store materials on top of electrical panels and equipment.
- When live electrical parts are exposed for inspection/service in a passageway or open area, the working space must be guarded to keep unqualified personnel away.
- When live electrical parts are exposed in a room or guarded location, warning signs should be posted forbidding unqualified persons to enter.
- When live electrical parts are exposed and the equipment is over 600 volts, the entrance to that area must be kept locked unless employees are supervised by a qualified person. A sign should be posted reading ‘Danger – High Voltage – Keep Out.’
- Adequate lighting should be provided around all electric equipment.
- Live parts of equipment at 50 volts or higher must be guarded against accidental contact either by 1) locating it in an area only accessible to qualified persons; 2) placing permanent screens/partitions around the equipment; 3) placing it on a platform or balcony only accessible to qualified persons; or 4) elevating it up above 8 feet from the floor.
- If electric equipment is susceptible to physical damage, e.g., overhead lighting, it should be protected with guards.
- All 120-volt receptacles in restrooms and on rooftops must be protected with a ground fault circuit interrupter (GFCI).
- If more than one extension cord is used or if one extension cord powers multiple pieces of equipment, the outlet must be protected with GFCI. For construction activities, extension cords must always be protected with a GFCI.
- Equipment must be protected from overcurrent with overcurrent protective devices (circuit breakers, fuses). These devices must be accessible to each employee or authorized management personnel.
- Circuit breakers used for facility lighting must be rated to operate as a switch. The breaker will be marked ‘SWD’.
- Temporary wiring, i.e., extension cords may only be used for a period of 90 days or less. It should be removed when the project (renovations, holiday lighting, construction) is complete.
- Flexible cords/cables should not run through holes in the floor, ceiling or walls, or through doorways or windows.
- Strain relief must be provided for cords/cables to prevent the pull on joints or terminal screws.
- Employees must not be exposed to live parts of appliances (other than open heating elements like toasters), lighting fixtures, or lamps.
- If equipment is in place or installed in a hazardous (classified) location, such as a room where flammable vapors can be released or where combustible dust is a hazard, it must be approved for that environment according to OSHA’s Class-Division system.
Safety-Related Work Practices
Now let’s focus on employee safety. There is not as much information contained in 1910.331-.335, so it’s easier to digest. OSHA addresses two groups of people – unqualified workers and qualified workers.
Unqualified Workers
Unqualified workers are those employees who face a risk of electric shock (above 50 volts) or other related injuries, but who have not been trained to recognize and avoid the hazards associated with electrical equipment. In other words, they are not trained nor permitted to work with live electrical components. Unqualified workers must receive some level of training that includes the following elements:
- Safety-related work practices that pertain to their job tasks; and
- Inherent hazards of electricity (high voltages, arc flash, lack of guarding, etc.).
Qualified Workers
If any of your employees have replaced a fuse, a circuit breaker, or conducted voltage testing, to name a few, they are technically doing “live” or “energized” electrical work. They should be considered your qualified workers, but don’t be too quick to label these workers right away. OSHA defines a qualified person as someone “who has received training in and has demonstrated skills and knowledge in the construction and operation of electric equipment and installations and the hazards involved.” Essentially, there are two pieces to the qualified-person puzzle: 1) Skills and knowledge related to the equipment; and 2) Training on the hazards. Your employees may be “qualified” to do a particular task or work on a certain piece of equipment, but they may not be qualified, i.e., they lack the skills and knowledge, for a different task or piece of equipment.
Qualified persons should be trained on the following elements:
- The skills and techniques necessary to distinguish between exposed live parts from other parts of the equipment;
- The skills and techniques necessary to determine the nominal voltage of exposed live parts;
- The clearance distances for overhead lines (if applicable);
- The approach boundaries for equipment at corresponding voltages;
- Proper use of special precautionary techniques, applicable electrical policies and procedures, PPE, insulating and shielding materials, and insulated tools;
- The construction and operation of equipment;
- Performing job safety planning;
- Identifying electrical hazards and assessing the associated risk;
- Selecting the proper risk control methods, including PPE; and
- Selecting the appropriate test equipment, using it safely, and interpreting it correctly.
There are additional requirements in this section beyond training. The major highlights are provided below.
OSHA requires the following:
- Safety-related work practices (some of which may have to be specific to your unique industry or equipment) must be used to prevent shock and other related injuries.
- All equipment must be worked in a de-energized state unless you have a proper justification – either it’s less than 50 volts, it poses a greater hazard to shut down, or it’s infeasible to shut down while completing your task, i.e., troubleshooting.
- If exposed live parts are not de-energized, the employees must be protected from both direct and indirect contact, e.g., conductive ladder, tool.
- Equipment that has been shut off but is not locked out/tagged out must be treated like it is energized.
- Employees must follow appropriate lockout/tagout procedures when de-energizing equipment.
- A qualified person (see definition above) must verify that electric equipment is de-energized and must inspect the equipment before it is ready to be re-energized.
- Only qualified personnel are permitted to work on energized equipment (including voltage testing on supposedly de-energized equipment).
- If working near overhead power lines, the lines must be de-energized and grounded or other protective measures must be used if this isn’t possible.
- Unqualified employees working near overhead power lines must stay at least 10 feet away from the lines (this includes vehicles and mechanical equipment).
- Qualified employees cannot get within a few feet on an overhead line unless they’re insulated from the line or from all conductive objects, or unless the line is insulated from them.
- Enough lighting must be provided in enclosed spaces containing live equipment in order for employees to work safely.
- Conductive equipment, e.g. uninsulated screwdriver; liquids, e.g. cleaning supplies; and apparel, e.g. jewelry, metal buttons, keychains must not be used or worn where they could contact energized equipment.
- Portable ladders must have non-conductive siderail, e.g. fiberglass, where they contact energized equipment.
- Only qualified employees can defeat electrical safety interlocks and only for a temporary amount of time.
- Employees must not raise or lower a piece of electrical equipment, e.g. power drill, by its cord.
- Cords should not be secured with staples or hung in such a way that the cord can be damaged.
- All cords must be inspected for external damage and signs of internal damage before they are used.
- Damaged or defective equipment must be removed from service and may not be used until it is repaired/replaced.
- If a circuit breaker trips, employees may not reset the breaker unless it’s clear that the breaker tripped because of an overloaded circuit. If the issue is repetitive (continues to trip, or fuses continue to melt), the fault condition must be investigated by a qualified person.
- Test equipment, such as a voltmeter, must be rated for the equipment it will be contacting and must be inspected before use.
- Employees must be provided with and must wear appropriate personal protective equipment (PPE) based on the electrical hazards presented (this includes arc flash protective clothing, safety glasses, an arc-rated face shield, insulated gloves, and hearing protection as required).
- PPE must be inspected before use and tested at certain intervals – for instance, rubber insulating gloves must be electrically tested before their first issue and every 6 months thereafter (note: if the gloves haven’t been used in the past 6 months, this testing requirement is extended to 12 months after the previous test date).
- Safety signs, symbols, and tags must be used where necessary to warn employees about electrical hazards, e.g. ‘Danger – Shock Hazard When Cover Removed.’
- Insulated fuse-handling equipment must be used to replace fuses when the fuse terminals are live.
Requirements Gaps
There are some problems with these employee safety-based requirements – they’ve got gaps. OSHA’s standard is old and it takes a long time to make updates. As a result, the requirements don’t adequately address arc flash/arc blast (not formally studied until 1993), which is a serious recognized electrical hazard. They also don’t address having an electrical safety program, safe work procedures for energized tasks, or arc-rated PPE. OSHA is well aware of these gaps, so they refer us to another consensus standard out there called NFPA (National Fire Protection Association) 70E, Electrical Safety Requirements for the Workplace. NFPA 70E is a thorough guideline that addresses electrical safety for employees. It has details on conducting a shock and arc flash risk assessment and protecting employees accordingly. NFPA 70E is revised every three years, and the latest edition is from 2015. Because revisions are made every three years, the standard recommends that electrical safety training for qualified workers be performed every three years.
How to Keep Your Employees Safe
Compliance with OSHA regulations is important, but it’s not the only thing that can keep your employees safe. If there are electrical hazards present at your workplace, and/or if you have employees that are at risk of electrical injury, it’s essential that you have a well-rounded Electrical Safety Program that incorporates shock and arc flash risk assessments (NFPA 70E).
Shock Risk Assessment
Conducting a risk assessment for electric shock is fairly easy if you’re referencing the NFPA 70E standard because it is based on voltage alone. For example, if an employee is working on a 480 volt AC system then he/she should wear, at a minimum, a class of rubber insulating gloves that is rated to at least 500 volts AC (class 00), if not the next class up (class 0, 1000 volts AC).
The voltage also determines what the NFPA 70E calls “approach boundaries”. There are two of them – 1) Limited boundary, past which point unqualified employees are not allowed; and 2) Restricted boundary, past which point qualified employees must be prepared to do live work and be protected (no conductive objects allowed past this boundary).
Arc Flash Risk Assessment
An arc flash risk assessment is more complicated and is typically contracted out to an engineering firm. In order to conduct the assessment, you need to know the short-circuit current and fault clearing time for each piece of equipment. Using this data, the incident energy level, i.e. heat level in calories per square centimeter (cal/cm2) and arc flash protection boundary (typically in inches) can be determined and your equipment labeled accordingly. The arc flash risk assessment essentially tells you “if something causes an arc flash/blast in this panel, this is how big it’s going to be.” These assessments shouldn’t just tell you how to protect yourself, they should also clue you in as to where you should target hazard reduction and make the equipment itself safer.
Other Program Elements
If your employees must perform live (energized) work, either because it’s infeasible or more dangerous to shut down the equipment, then live electrical safe work procedures should be developed. If the task is non-routine and you don’t have a safe work procedure, then employees should fill out a live electrical work permit before beginning the task. NFPA 70E has an example of a live electrical work permit that can be used in such situations.
Your program should also incorporate how your facility is going to manage contractor safety regarding electrical work, preventative maintenance/upkeep of equipment, and other specific OSHA requirements (several of which are included in the bulleted lists above).
Electrical Safety Tips
Whether the electrical safety requirements apply to you or not, all companies and employees should follow these safety tips:
- Have a healthy respect for electricity, no matter the voltage or current level. Low voltage doesn’t always mean low hazard.
- #1 Rule: when possible, work de-energized according to proper lockout-tagout procedures. You should have a very good justification for doing any live work.
- Assume that all wires are energized, even if they appear to be insulated.
- Do not use electrical equipment that shocks, smokes, smells, is damaged, or has burn marks. Repair or replace it.
- Never repair electrical cords or equipment unless you’re qualified; and don’t repair cords with electrical tape.
- Never operate electrical equipment while standing in water (it may hurt).
- In wet/damp locations, ensure your electrical circuit or receptacle is equipped with a ground fault circuit interrupter (GFCI).
Hellman & Associates, Inc. provides Electrical Safety/Arc Flash training for qualified employees (including refresher courses) and electrical awareness safety training for unqualified employees. We can also help you build/implement an Electrical Safety Program and develop safe work procedures. Give us a call if you need specialized electrical safety training or program development.
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