Prohibited Approach Boundary

By R.W. Hurst, Editor

The prohibited approach boundary (PAB) is critical in electrical safety, particularly when dealing with energized electrical equipment. It defines the closest distance a worker can approach an exposed energized component without risking serious injury. The National Fire Protection Association (NFPA) 70E standard outlines the guidelines for establishing and adhering to approach boundaries to ensure worker safety.

The Three Limits of Approach Boundaries

NFPA 70E defines three distinct approach boundaries for electrical work:

Limited Approach Boundary: This is the outermost boundary beyond which a shock hazard exists. Unqualified personnel must not cross this boundary unless escorted by a qualified person.
Restricted Approach Boundary: This boundary lies within the limited approach boundary and signifies an increased risk of shock due to potential arc-over and inadvertent movement. Only qualified workers may enter this zone, and they must be adequately insulated or guarded from live parts.
Prohibited Approach Boundary: The innermost boundary, where work is equivalent to making direct contact with the live part. Only qualified personnel with specific training, an approved energized electrical work permit, and appropriate arc flash PPE can cross this boundary.

What are the Requirements for Working in the Prohibited Approach Boundary?

Working within the PAB requires strict adherence to safety protocols to prevent electrical shock and arc flash incidents. The requirements include:

Qualified Person: Only qualified persons with specific training in avoiding electrical hazards can work within this boundary.
Personal Protective Equipment (PPE): Workers must wear appropriate arc flash PPE and shock protection equipment. This includes insulated tools, rubber gloves, and flame-resistant clothing to protect against potential incident energy and arc flash boundary hazards.
Work Permit: Before commencing any work, a detailed work permit outlining the scope of the work, the hazards involved, and the protective measures required must be issued.
De-energization: The electrical system should be de-energized before work begins. If de-energization is not feasible, other protective measures, such as insulating barriers or guards, must be implemented.

How to Determine the PAB?

The PAB is determined based on the voltage of the exposed energized parts. NFPA 70E provides tables that specify the distance from an exposed piece of electrical equipment for various voltage levels. For example, for systems operating at 750V to 15kV, the PAB is typically calculated to ensure that any inadvertent movement does not result in contact with live parts.

The calculation considers the potential for electrical arcing and the need to prevent any degree burn or other injuries. Incident energy analysis is often conducted to determine the appropriate boundaries and necessary PPE for workers.

Barricades and the limited and restricted approach boundaries

Barricades can be placed to demarcate the limited approach boundary and prevent unauthorized personnel from entering the hazardous zone. However, they should not be placed closer than the limited approach protection boundary, as this would restrict the movement of qualified workers who need to access the equipment. The barricades should be clearly marked and visible to ensure everyone understands the safety restrictions.

Additional Considerations

Beyond the PAB, other safety measures are essential for electrical work. These include using insulated tools, maintaining proper clearances, and de-energizing equipment whenever possible. Regular training and refresher courses on electrical safety and NFPA 70E standards are crucial for both qualified and unqualified personnel.

Understanding and respecting the PAB is vital for ensuring the safety of workers in electrical environments. Adhering to NFPA 70E guidelines, conducting thorough risk assessments, and using appropriate PPE can minimize the risk of electrical shock and arc flash injuries. Electrical safety is a shared responsibility, and every worker plays a role in preventing accidents and promoting a safe work environment.

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Evluma Launches Line of Post Top Globes to Complement LED OmniMax

March 12, 2020, Renton, WA…Street and area lighting manufacturer Evluma, announces the release of a new globe accessory line, OmniMax Lighting Solutions (OLS) to complement their OmniMax family of LED replacement lamps. OLS is a custom, curated selection of spherical and acorn style globes for decorative streetlights. The OmniMax is a Bluetooth-connected, screw-in replacement lamp for use in decorative post top globe and acorn lights. The release of a globe line to complement the OmniMax is designed to make the HID to LED conversion and maintenance process easier for Evluma customers.

Customers executing a retrofit project can conveniently purchase a replacement globe at the same time they purchase the OmniMax. “The wide variety of styles and materials offered means that we can typically provide a customer with a globe that matches an older style,” said Marketing Director, Cathleen Shattuck. “Customers can refresh globes simultaneously with OmniMax installation to save on labor, or if they suddenly discover damage to individual light fixtures, we can quickly provide them with a solution. Our high level of customer service means we are well-adapted to quick turnaround on orders of any size, keeping the process convenient and low cost.”

Using OmniMax, municipalities, utilities and electric departments converting post top fixtures from HID to LED can do so in under 5 minutes a fixture. The OmniMax is available in both Premium and Standard models. Premium models are Bluetooth-enabled and are compatible with Evluma’s wireless control application, ConnectLED. Both models carry a ten-year warranty and offer Evluma’s signature low-glare illumination.

About Evluma

Formed in 2008, Evluma is committed to developing affordable, long-lasting and environmentally low-impact LED lighting solutions that fundamentally change the landscape of the outdoor utility lighting market. Evluma’s high standard of customer service and background in innovative lighting technologies, automation and software design creatively ideate and inform its utility-grade products. Evluma is located in Renton, WA, USA.

09/24/20

Evluma's Build-Your-Own Acorn is an Affordable Answer to Decorative Streetlight LED Upgrades

Street and area light manufacturer Evluma announces the release of Build-Your-Own Acorn; a full-fixture, decorative streetlight replacement solution that includes the customer’s choice of acorn globe, finial and capital fitter. This solution is designed for utilities, municipalities, facilities and property managers looking to upgrade their existing decorative lighting from HID to LED and features the OmniMax™ LED lamp as its light source.

“Build-Your-Own-Acorn is a tailored solution that puts control in the hands of the customer,” said Evluma Product Manager Jason Dobbs. “With the value-driven OmniMax at the center of quality, cost-effective options, this is an affordable approach to complete head replacements. Build-Your-Own-Acorn offers the freedom to replace and repair fixtures without being locked into a proprietary OEM solution that may be hard to change later and typically costs more. It’s everything but the pole.”

Build-Your-Own Acorn includes multiple styles of acrylic and polycarbonate globes, in addition to a cast aluminum capital fitter. The capital fits 3 inch and 4 inch poles and is offered in black or green. The 70W OmniMax LED lamp is offered in six different color temperatures ranging from 2000K-5000K in either the Premium or Standard. OmniMax Premium includes Evluma’s patented, maintenance-saving Photocontrol Failsafe™ and compatibility with Evluma’s Bluetooth lighting app ConnectLED™. OmniMax Standard ships without connectivity features or Photocontrol Failsafe built-in.

“Photocontrol Failsafe means never having to replace a failed photocontrol ever again,” said Janine Soper, Evluma’s Regional Sales Manager. “With ConnectLED, the OmniMax Premium can be quickly dimmed or programmed with a dimming schedule, offering additional aesthetic and energy saving opportunities,” said Janine.

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High Voltage, Inc. is an American test equipment manufacturing company located in rural Copake, NY. We are known for high quality, easy to use equipment and for our commitment to providing the best customer and product support in the industry.

As we matured we expanded into larger products. Cable fault locators (thumpers) as well as higher power ac (HPA) dielectric testers as might be used in a factory environment. Our HPA line of ac testers are available with outputs up to 300 kV ac and power levels up to 40 kVA and can be customized with various levels of control sophistication.

Our new PAR line of ac dielectric testers are designed to meet the needs of those who need power levels up to 250 kVA, to be able to test their highly capacitive test loads. Using ac resonant technology outputs of 50 kV at 5A (for example) are possible with an input of only 230 v, 90 A. That is an input of 20 kVA for an output of 250 kVA. (Model PAR-50250FC5)

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The variable reactor looks similar to a transformer but has a moveable core that allows the inductance value to vary to match the capacitance of the load, thereby achieving resonance. This effectively cancels the load capacitance, as far as input power requirements are concerned. Once in resonance, the input voltage is increased until the desired output voltage level is achieved. For a capacitive load that must be tested at power frequency the PAR reduces power requirements, as well as test equipment size by one tenth to one thirtieth, compared to a test transformer.

The HVI PAR family of resonant as dielectric testers are perfect for power frequency testing of power cables, rotating machinery, bushings, instrument transformers, transformers, shunt reactors, and many other products.

For more info please contact sales@hvinc.com to discuss your application.
For more information on these and other high voltage test products, contact High Voltage, Inc. at www.hvinc.com, sales@hvinc.com, or call 518-329-3275.

03/07/22

Evluma Launches Low-Glare LED Roadway Luminaire

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This sleek and stylish luminaire was designed with RP-8-18 roadway requirements in mind. The unique optical design offers a combination of roadway performance and glare control unprecedented in the industry. “RoadMax is an advancement of Evluma’s reputation for low-glare, visually-pleasing outdoor lighting,” says Taisha Bezzo, National Sales Director. “RoadMax addresses contemporary concerns regarding disability glare and light trespass from roadway lighting while maintaining exceptional pole spacing.”

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