The NEC and more recently the NFPA 70E state that any of the The NEC and more recently the NFPA 70E state that any of the following types of electrical equipment located in manufacturing and commercial establishments (other than dwelling occupancies) must be field marked with a warning label if subject to examination, adjustment, service or maintenance while energized:

• Switchboards
• Panelboards
• Industrial Control Panels
• Meter Socket Enclosures
• Motor Control Centers

The labeling requirement is the responsibility of the employer, not the manufacturer or installer of the equipment.

In accordance with the 2012 edition of the NFPA 70E, labels applied to the required electrical equipment prior to September 30, 2011 are acceptable if they contain the available incident energy or required level of PPE. However, labeling does need to be applied if the equipment is ever modified or upgraded in any way. For example, at least one OSHA representative has stated that he considers changing a fuse or a breaker to be a modification that would require labeling.

Many employers are also labeling bus ducts and other electrical equipment not specifically called out in article 130.5 (C). Again, the logic is the same. If live electrical work may be performed on these systems, the risk of accident and injury exists. Clearly it is better to properly warn workers of the hazard.

The NFPA and NEC requirement states that the marking must be located so that it’s clearly visible to qualified persons before they begin work. Typically, the label is placed outside the panel or enclosure door.

In some cases, however, companies choose to put the label inside the door (e.g., to protect it from harsh environments), but this should only be done if the door must first be opened (allowing the label to be seen) before the panel face or enclosure can be removed. The key point is that the label be easily noticeable by workers before they may be exposed to any potentially dangerous live parts.

New Regulations, NEC Labeling Requirement

OSHA is now citing and fining employers for failure to protect employees from the dangers of arc flash. For guidelines on best practices for protecting employees, OSHA refers employers to the 2012 edition of NFPA 70E standard, “Standard For Electrical Safety In the Workplace.”

The NFPA 70E 2012 edition instructs employers to conduct an arc flash analysis to determine the amount of thermal energy that could be generated in an arc flash incident. The information is then used to define a flash protection boundary around the potential source, and to determine the level of arc-rated apparel and other personal protection equipment required when employees cross the boundary while they work on or near exposed live parts.

In addition, the National Electric Code®(known as NFPA 70, which is different than NFPA 70E) added a requirement in 2002 mandating that potential arc flash hazards be labeled to warn of the hazard. The requirement, covered under Article 110.16, was updated and expanded in the 2005 version of the NEC. In the newly updated 2012 edition of NFPA 70E, these requirements from the NEC have been included to streamline industry best-practices. These requirements can now be found under article 130.5 (C) within the 2012 edition of NFPA 70E.

Arc flash is a short circuit through air that flashes over from one exposed live conductor to another conductor or to ground. Arc flash incidents are common and costly, and the frequency of reported accidents is increasing – making arc flash a very hot topic within OSHA and the overall safety industry.

What Causes Arc Flash? Arc flashes can be caused in a variety of ways:

• Just coming close to a high-amp source with a conductive object can cause the electricity to flash over.
• Dropping a tool or otherwise creating a spark can ignite an arc flash.
• Equipment failure due to use of substandard parts, improper installation, or even normal wear and tear.
• Breaks or gaps in insulation.
• Dust, corrosion or other impurities on the surface of the conductor.

How Common Is Arc Flash? In the past, if someone suffered burns in an electrical accident, people thought the burns were caused by the electrical shock passing through the body. Electrical shocks can cause burns. But what research has shown is that most burns from electrical accidents actually come from arc flash.

According to the NFPA 70E-2004 standard, the majority of hospital admissions due to electrical accidents are from arc flash burns, not from electrical shocks. Of the approximately 350 persons killed in the work place by electricity last year, roughly 50% were related to arc flash

A report compiled by Capelli-Schellpfeffer, Inc., estimates that five to 10 arc flash explosions happen in the USA every day, resulting in 1 to 2 deaths per day.

That figure only takes into account incidents where victims were sent to special burn centers. The number does not include cases sent to regular hospitals or clinics, nor unreported cases or near misses.

NFPA 70E-2012 states that each year more than 2000 people are admitted to burn centers with severe arc flash burns.

Install Appropriate Surge Suppression Devices
Surge suppression devices regulate the voltage supplied to an electric device either by blocking or diverting voltages above a safe threshold to ground. Surge suppression devices should be installed in a staged, cascaded or layered manner to divert surges of various strengths at different points with an electrical system. Surge suppressors installed at the high exposure service entrances, where power enters the facility, establish the first line of defense against high powered, externally generated surges. These devices will address surges caused by lightning, power company grid switching, power system faults, severe weather, and neighboring facilities.

The second layer of defense is established by installing surge suppressors at the distribution panel, which distributes power throughout the facility. These surge suppressors protect against high to medium surges that may be externally or internally generated. Installing devices at branch panels addresses lower level surges generated by a wide variety of load equipment including lighting controls, office equipment and industrial systems. In addition some equipment and circuits may require special attention. Process control, sensing and monitoring devices may all require individual protection. Telecommunication and data circuits are extremely vulnerable to relatively low-level surges and need to be protected at the point of entry.

While surge suppression devices are the major tool minimizing surge damage, they do not always prevent damage cause by direct lightning strikes, nor the rarely occurring temporary over-volts cause by sever faults in power company cables.

Install an Uninterruptible Power Supply if Dictated by Operations
Surge suppression devices do not provide back-up power. An uninterruptible power supply is an electrical apparatus that provides emergency power when an input power source fails. This device differs from an emergency power system or standby generator in that it provides near-instantaneous protection from input power interruptions for a relatively short period to allow time to properly shut down protected equipment or bring an auxiliary power source on line. This type of device is typically used to protect computers, data centers, telecommunications equipment or other electrical equipment where an unexpected power disruption could cause injuries, fatalities, serious business disruption and data loss.

Protecting Against Power Surges
Small businesses, manufacturers, multi-national corporations, research facilities, and many other businesses recognize the need to address power surge risks – and the benefits that accrue from doing so. The general approaches to managing power surge risks are relatively straight forward. Still specific applications must be customized to fit the unique needs of diverse operating environments and circumstances. Such applications are most appropriately designed and installed by experienced experts. The basic tools to minimize the impact of power surges are:

• Install surge protection against external sources at the point where external power is supplied to the business.
• Make sure that all systems have a common “ground” and enter the building within a few feet of each other.
• Keep communications and low voltage lines away from power cables within the facility and, when possible, have them cross at right angles.
• Add surge protection at distribution panels within the facility if it includes large motors, welders, etc.
• Add surge protection for individual pieces of sensitive equipment to the power connection and to any communications lines (e.g., phone cords, Internet cables and coaxial cables – cable television or cable Internet type connections).

Assure Electrical and Telecommunications systems are Designed and Installed to Minimize Power Disruptions
The appropriate design and installation of the wiring within a facility is extremely important in mitigating surges. A building’s electrical system needs to be properly grounded in accordance with the National Electrical Code. All telephone, cable and satellite wires need to be bonded to the same grounding point. Communications cables need to be installed with appropriate separation from power cables which can induce surges. Telecommunications rooms need to be wired to minimize electrical disturbances and fitted with electrical equipment, temperature controls and furnishings that dampen the likelihood of disturbances.

Power or voltage surges are brief bursts of energy caused by sudden change in the electrical conditions of a circuit; they are virtually inevitable. Wherever electrical or electronic equipment is used, power surges can and do occur. While often lasting only a millisecond, power surges can raise the voltage in electronic circuits from a few hundred to as much as several thousand volts. They are one of the most sever, common and immediate dangers to modern, sensitive electronic equipment. Business Week estimates that power surges cost $26 billion a year in lost time, equipment repair and replacement costs.

What Causes Power Surges?
• It’s estimated that 60 percent to 80 percent of power surges are caused by events or problems arising within the facility housing the electrical and electronic equipment. The balance is generated by external events that affect the internal electrical system through power cords, telephone lines, and cable, satellite and antenna lines. Events causing surges include:
• Local Power System/Utility Problems – Poor power quality is one of the major causes of downtime. The most common source for externally generated surges is the local electric company. Problems and point of failure include faulty wiring by a utility, equipment breakdowns, downed power lines, grid shifting (reallocating stored energy to match demand), and capacitor switching (a routine, daily event.)
• Large users of the same power line at other facilities can also create power surges. Heavy electrical equipment that frequently turns on and off, such as high-powered motors, elevators, or heating/air conditioning equipment, creates sudden, brief demands for power that can upset the steady voltage flow in the electrical system and result in power surges may also be caused when two power lines come into contact with each other as a result of vehicle crashing into power poles, falling tree limbs, ice storms and even animals.
• Lighting – Power surges caused by direct lightning strikes are rare events, accounting for only two percent of power surge damage. Lighting is however a very common occurrence, striking the surface of the Earth about 100times every second. When lighting directly strikes exposed cables feeding electric equipment, the extremely large, overwhelming power surges it produces are devastating. Importantly, lighting does not need to actually directly hit an object on the ground to induce a power surge. Lighting can create strong electromagnetic fields, which can induce a power surge that affects power, telecommunications and radio frequency transmission lines; these in turn affect electric equipment inside a facility. Due to the low voltages normally used in data transmission cables and the sensitivity of the connected electronics, communications cables are extremely susceptible to induced voltage surges.
• Events Arising Within a Facility – Switching high-powered electrical devices like elevators, air conditioners, refrigerators, pump, compressors and motors on and off are common causes of internally generated surges. The ignition and interruption of electrical arcs used in welding devices can also cause surges, as can the tripping of fuses and circuit breakers. Typically, but not always, these surges are rather small and degrade electrical equipment, rather than destroy it.

What Type of Businesses and Equipment are at Risk
Every business relies on modern electronic equipment to some degree –and such equipment can be easily damaged or weakened by surges. Businesses face significant threats if their products and services rely on sustaining continuing operations supported by electronic or telecommunications equipment, or if malfunctions of sensitive electronic equipment change the nature of critical products and/or services. Businesses with electronic systems in hazardous locations, such as potentially explosive atmospheres, obviously are exposed to catastrophic risks. Businesses located in areas with poor local power supplies or where weather conditions making lightning strikes more likely also face increased risk of damage from power surges.

Examples of businesses and equipment at risk include:
• Manufacturing operations where there is significant use of motors and other high voltage equipment.
• Businesses that depend on computers, and use office equipment such as printers, faxes and photocopiers.
• Businesses that use security or alarm systems, telemetry or monitoring networks, bar code scanners, or thermostats.
• Healthcare facilities with equipment monitoring and assisting life support systems.
• Information and order processing operations with heavy reliance on communications.

Older homes often times have many electrical issues…..
Most wires in your home have a protective covering, or insulation, which is designed to protect the wire from arcing when touched. As your home ages wire insulation may become frayed, cut or burned. Electrical wires without completely intact insulation are extremely dangerous and could results in fires or electrical shock. Other hazards include wire splices not enclosed in junction boxes or aluminum wiring which has anodized.  

The U. S. Consumer Product Safety Commission recommends an electrical inspection of your home every 10 to 40 years. Many older homes were built when the electrical demand was not what it is today. Your state-of-the-art appliances and electronic systems may be placing a seriously overloading on your home’s electric system.

If you experience buzzing or charred outlets and switches…..
Outlet and switches should never buzz, and their face or cover plate should never be hot to the touch. If either example is present in your home it is a clear warning sign. These signs often indicate a faulty device, loose wiring or arching between the wire conductors and the device, box or cover plate. Charred devices should be inspected immediately.  It’s normal for dimmer switches and their cover plates to be warm, but they should not be hot.

If you experience frequent breaker trips…..
It’s perfectly normal to go years without having to reset a tripped breaker or replace a blown fuse. If you have a circuit that trips often, there’s a good chance it’s overloaded, or there could be a short or fault somewhere in the circuit or on any devices connected to the circuit.

If you experience dimming or flickering lights…..
Dimming and/or flickering lights is another common example of circuit overload or problem wiring. Flickering lights can result from a damaged fixture wire, a problem with the switch or a fault somewhere on the circuit. In older homes with 60-amp service panels (breaker boxes), underpowered fixtures and appliances may indicate that the electrical system is being overtaxed and should be upgraded.

What should you do if you observe any of the above conditions?
Do not touch exposed wires or observed problem(s).
If possible de-energize the wire by turning off power at the switch, circuit breaker or fuse.
Call Branham Electric to schedule an electrical inspection of your home today! Mention this blog and receive a 10% discount.