NFPA 70E Electrical Safety

Written by Steve Hudgik

How does NFPA 70E help your employees be safe from injuries caused by electrical incidents?

NFPA 70E (also known as the Standard for Electrical Safety in the Workplace) provides standards for safe work practices for working on existing electrical equipment or installing new electrical equipment.

What is the extent of workplace electrical hazards?

Based on data from the NIOSH National Traumatic Occupational Fatalities (NTOF) surveillance system, electrocutions are the fifth leading cause of death in the workplace, averaging 7% off all workplace fatalities.

In a paper published by NIOSH called: "WORKER DEATHS BY ELECTROCUTION - A Summary of NIOSH Surveillance and Investigative Findings" information is presented that reveals it does not take much current to cause an electrical injury. The paper gives the effects of 60 HZ AC current passing through the chest as*:

1 mA  - Barely perceptible
16 mA - Maximum current an average man can grasp and “let go”
20 mA - Paralysis of respiratory muscles
100 mA - Ventricular fibrillation threshold
2 Amps - Cardiac standstill and internal organ damage

The common amperage at which a fuse or breaker opens the circuit is 15 to 20 amps. This is much higher than the current flow that will injure people.

NFPA 70E Electrical Safety – How Are Electrical Accidents Prevented?

The best way to prevent electrical accidents is to ensure that workers are never exposed to energized equipment or circuits. Set a goal of minimizing, and if possible eliminating, the number of energized equipment work permits (EEWP) that are issued. Placing equipment in an electrically safe condition (de-energized) eliminates the possibility of an electrical accident.

Have a Lock Out/Tag Out program that specifies the procedures for locking out de-energized equipment. Include procedures for testing and ensuring equipment is actually de-energized.

Be aware that even the electrical tasks needed to be done to de-energize equipment, such as racking breakers, expose workers to electrical hazards. Racking a circuit breaker involves breaking an electrical circuit and this presents the risk of an electrical arc flash. As a result PPE is required when racking breakers.

If work must be done on energized equipment or circuits, you need to be able to justify that need. OSHA 1910.333(a)(1) states: "Live parts to which an employee may be exposed shall be de-energized before the employee works on or near them, unless the employer can demonstrate that de-energizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations. Live parts that operate at less than 50 volts to ground need not be de-energized if there will be no increased exposure to electrical burns or to explosion due to electric arcs."

Note: Inconvenience is not an adequate justification for not de-energizing equipment or circuits before working on them.

In addition, NFPA 70E Article 110.8(B)(1) requires an Electrical Hazard Analysis, to determine the potential for and hazard level of an arc flash, before work is performed on live equipment operating at 50 volts and higher.

NFPA 70E Electrical Safety – What Are The Hazards?

Although arc flash often gets the headlines, most electrical injuries and fatalities result from electrical shock. Even ensuring that no work is done on energized equipment will not eliminate the potential for electrical fatalities and injuries. The OSHA monthly workplace fatality report shows a significant number of electrical fatalities result from contact with overhead wires – most often with a crane boom or metal ladder. You need to ensure that your employees, as well as contractors, are fully trained on this type of electrical hazard in your facility.

NFPA 70E Electrical Safety – Protecting Workers

If work must be done on energized equipment, the first line of defense is to ensure all employees are trained. To be safe your employees must:

• Be familiar with the equipment they are working on.
• Know the hazards of the equipment.
• Be qualified to work on the equipment.
• Know what safety measures to take.

OSHA requires that employers train their workers proactively. Some of OSHA's standards that relate to training requirements include:

The employer must ensure workers are trained and following safe work practices. It is the employer's job to ensure safety. OSHA 29 CFR 1910.269(a)(2)(iii) - "The employer shall determine, through regular supervision and through inspections conducted on at least an annual basis, that each employee is complying with the safety-related work practices required by this section;" and, "Note: OSHA would consider that tasks that are performed less often than once per year to necessitate retraining before the performance of the work practices involved."

The employer must ensure workers are properly trained for the electrical work they need to do. OSHA 29 CFR 1910.332 - "The training requirements contained in this section apply to employees who face a risk of electric shock that is not reduced to a safe level by the electrical installation requirements of 1910.303 through 1910.308."

And OSHA 29 CFR 1910.269(a)(2) - "Employees shall be trained in and familiar with the safety-related work practices, safety procedures and other safety requirements in this section that pertain to their respective job assignments. Employees shall also be trained in and familiar with any other safety procedures (such as pole top and manhole rescue) that are not specifically addressed by this section, but that are related to their work and are necessary for their safety."

NFPA 70E provides the safe work practices that employees need to be trained in using. Here are six steps to follow for electrical safety:

1. TURN OFF THE POWER. Always work de-energized whenever possible.
2. When work must be done on energized equipment, require an Energized Electrical Work Permit (EEWP). The EEWP should require the signatures of everyone involved with the equipment, as well as management. Some companies specifically make the EEWP difficult to obtain, providing an additional incentive to find a way to de-energize the equipment.
3. Have a detailed description of the work and a written plan for safely performing work on the specific electrical equipment being serviced.
4. Use PPE (Personal Protective Equipment), and electrically safe tools, as specified in NFPA 70E.

In addition to the above four steps, which are required by NFPA 70E, we recommend two additional steps be added to your list:

5. Before, during and following electrical work conduct periodic safety audits. This helps ensure workers are continuing to follow electrical safety procedures. Supervisors, management and safety staff should get out into work areas to see what employees and contractors are doing. Conduct job hazard analysis, job safety checklists, and regular evaluations of how tasks are accomplished and evaluate them for ways to improve safety and eliminate waste
6. Keep electrical equipment properly maintained. Properly maintained equipment is safer and ensures that the safety features of the equipment are properly functioning.

NFPA 70E Electrical Safety – Arc Flash Safety

OSHA statistics show that few arc flash incidents result in a fatality, but arc flash results in extremely serious injuries. They result in severe burns, scarring, tissue death, lost limbs, blindness, hearing loss and other very serious injuries.

Arc flash injuries are not direct electrical injuries. They are the result of an electrical arc which results in a blast or explosion. It is the heat of the explosion, and the accompanying blast debris and vaporized metal, that cause the injuries.

NFPA 70E specifies electrical safety measures that need to be taken to protect workers from arc flash injuries. Work done within a area exposed to an arc flash hazard (within the arc flash boundary) must be done by a qualified person. The NFPA 70E definition states: "Qualified Person One whom has the skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training on the hazards involved." A qualified person will know the NFPA 70E safety requirements and follow them.

NFPA 70E Electrical Safety - Using Labels and Signs For Electrical Safety

An effective means of communicating electrical safety information is to use labels and signs. NFPA 70E requires the use of labels to warn about arc flash hazards. In addition, labels and signs are required by OSHA in general to warn about hazards. But labels and signs can do more to help improve safety. They are used to provide safety procedures, remind staff about required permits and LOTO, provide maintenance information, and to effectively communicate other information right at the location where it is needed.

The way to have the labels and signs you need is to have a DuraLabel printer. DuraLabel label printers are the versatile label printers that can handle all of your safety labeling needs. Call 1-888-326-9244 today and ask about the special DuraLabel kits available for ensuring compliance with NFPA 70E labeling requirements.

http://www.cdc.gov/niosh/docs/98-131/pdfs/98-131.pdf