Overview

Introduction to the Distribution Safety and Work Practices Project

2022 updates | 2021 deliverables | Past research

Project Description

Because electricity distribution involves multiple risks for both the public and utility workers, utilities put in place many risk-reducing procedures and processes. Improvements are always possible; new practices, protective approaches, equipment, tools, and technologies must be assessed carefully to evaluate the impact on worker and public safety. The goal of this research is to evaluate risks, protective approaches, and equipment and to investigate new technologies to improve safety.

Research areas include grounding and personnel protection, arc flash, downed conductors, and tools and technologies aimed at improving safety.

The operation of distribution circuits exposes workers and the public to hazards, including contact to energized objects (shock), arc flash from a system fault (burns), and step and touch voltages. This project aims to focus on these risks through research on:

  • Grounding and personnel protection
  • Arc flash analysis and protection
  • Detection and reduction of live, downed conductors
  • Stray and contact voltage
  • Manhole events
  • Evaluation and use of protective equipment
  • Technologies to improve worker safety

Key Research Question

What are the areas of greatest risk to workers and the public associated with distribution delivery, and what are the key technical challenges to reduce risk and improve safety for workers and the public?

Objective

Operation of distribution circuits exposes hazards to workers and the public, including contact to energized objects (shock), arc flash from a system fault (burns), and step and touch voltages. Utilities employ many approaches to reduce these risks. Protection approaches include practices for safe operations, training, and tools along with personal protective equipment designed to protect workers. This project aims to evaluate these risks, the scenarios where accidents are likely to occur, and the protection approaches to help utilities reduce risks and improve safety to workers and the public.

Approach

This project focuses on safety while working on or around utility distribution equipment, for utility workers and for the public. Focus areas include practices, equipment, and technologies to help utilities improve safety. The Safety and Work Practices research project for 2022 consists of the following tasks:

Backfeeds: The EPRI safety task force identified backfeed from distributed energy resources as the highest research need. These backfeeds can increase hazards to workers and can lead to energized downed conductors. To evaluate the risks and identify improvement options, EPRI plans to evaluate distributed energy resources (DER) technologies and aggregate contributions from inverters. In addition, review of lockout-tagout procedures may identify options to reduce risks.

Downed-Conductor Prevention and Detection: Downed conductors remain a challenge for electric utilities. EPRI has investigated and evaluated various approaches to downed conductor detection, including electrical measurement, high-speed signal processing, and methods based on advanced metering infrastructure (AMI). In 2022, plans are to continue to evaluate approaches to detecting downed conductors. This will include use of reclosers and distribution automation along with use of AMI.

Arc Flash: Arc flash is a hazard to workers, and an effective worker-protection program involves many facets that touch on work methods, personal protective equipment, system protection, and analysis. In 2020, EPRI produced an arc-flash guidebook that covers recent changes in the industry. For 2022, EPRI plans to evaluate battery systems to include in this guidebook. EPRI also plans to evaluate arc flash in utility scenarios and how that compares with industry arc-flash calculations and protective approaches. Another planned area of focus is arc-rated fabrics and clothing and evaluation tests.

Protective Equipment: Utility workers rely on many types of protective equipment to enhance their safety, including insulating gloves and sleeves, hotsticks, rope, flame-resistant clothing, insulating boots, and more. In 2021, EPRI produced an online reference on protective equipment. The main plan for 2022 is testing the mechanical integrity of insulating gloves and evaluation of aged samples.

Technology for Workers: EPRI intends to continue to investigate digital systems to improve safety for workers. One approach is to use images to verify good usage of insulating covers and otherwise identify safety issues on structures. This could be based on image processing, artificial intelligence, or other advanced technologies.

Practices: Contact to energized lines remains the number-one threat during live work. To reduce these risks, EPRI intends to focus on practices for insulation and isolation.

Research Value

These research tasks can help utilities improve safety for the public and utility workers. Specifically, the research results could help utilities:

  • Improve grounding approaches
  • Improve public and worker safety through leading approaches for downed conductor detection
  • Reduce hazards to workers from arc flash
  • Better use protective cover-up
  • Protect workers from contact to energized lines by enabling technology to reinforce better practices for line coverings
  • Effectively implement voltage-detection technologies to warn of hazards

Task-Force Roles

The Distribution Safety Task Force advises the Distribution Safety Project. This task force is generally staffed by subject-matter experts in areas related to public safety, worker safety, and work methods.

This task force meets several times per year by WebEx or in person. There is usually one in-person meeting per year held in conjunction with the other P180 task forces. The in-person meeting is normally held in Spring in Lenox, MA, or Charlotte, NC.

Members are encouraged to participate in several ways:

  • Attend task-force meetings
  • Review and comment on reports and findings
  • Provide materials for testing or evaluation
  • Provide information on your company’s standards or practices (a survey for example)
  • Attend testing at EPRI laboratories
  • Present to the task force on company issues or initiatives
  • Submit safety incidents for EPRI review
  • For safety-related equipment failures, submit equipment to EPRI for forensic analysis
  • Reach out to Tom Short or other EPRI staff on matters related to safety and work methods

This task force is also a good opportunity to meet safety experts at other participating companies.

Common Questions

How do I subscribe to the task-force mailing list?

How do I unsubscribe to the task-force mailing list?

Who can attend task-force meetings?

  • Task-force meetings are for funders of the appropriate P180 project. This includes task-force members and guests from sponsoring companies.

Are there specific membership requirements?

  • The only requirement is to fund P180.004. Membership is rather loose. There are no meeting attendance requirements.

Can my company have more than one task-force member?

  • Yes.

Can I share task-force material within my company?

  • Yes.

Can I share task-force material outside my company?

  • Generally not. There are exceptions, so if you have a need, please contact Tom Short.

Are discussions covered by a non-disclosure agreement?

  • Yes. All EPRI member agreements include non-disclosure clauses.

If my company isn’t funding this, how can I sign up?

  • Each company has their own methods for selecting components of the annual EPRI research portfolio. Contact your METT for more information. Technical advisors from EPRI’s member services can also help. Find contact information here.

Collaborative Supplemental Projects

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Arc Flash Testing of 480-V Bypass Meter Sockets and CT Cabinets

Arc flash can be very equipment specific. This project aims to test equipment that doesn’t have adequate industry testing. Without industry testing, the fallback arc-flash estimates lead to burdensome PPE. This project aims to clearly define existing hazards, based on actual testing, to show employers the hazard and allow employers to provide sufficient PPE.

  • Determine hazards for various bypass configurations and CT cabinets

  • Explore simple modifications that could reduce risks

  • Determine most appropriate levels of PPE

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Advanced Applications to Assist the Distribution Workforce

This project aims to demonstrate digital technologies to assist the distribution workforce in complex and precision tasks. Plans include vendor demonstrations of digital work aides and demonstration of applications to quantify performance versus typical work methods.

  • Demonstrate digital technologies to assist the distribution workforce in complex and precision tasks
  • Develop guidance, based on utility SMEs, for vendor demonstrations of digital work aides
  • Engage with advanced technology vendors to demonstrate application approaches and technology options
  • Evaluate demonstration applications to quantify performance versus typical work methods

EPRI participants can engage EPRI with supplemental projects. When a company funds EPRI annual research, 25% of the funds are set aside as self-directed funds (SDF). Utilities can use this to fund supplemental projects. Please contact your METT for more information on how supplemental project funds are allocated in your utility.

For more on supplemental projects, see here. To discuss project ideas, contact Tom Short.

Implementation Opportunities

Supplemental projects can also be one-on-one efforts. Companies allocate their self-directed funds in different ways. Options for these projects can include:

  • Field pilots of technologies
  • Integration of research results
  • Teardowns of failed equipment
  • Test specific equipment or scenarios

Examples related to current research could include:

  • Pilots of real-world use of voltage detectors
  • Implementation of arc-detecting technologies for downed conductors

Services and Capabilities

EPRI has several capabilities available to utilities as part of research work, supplemental projects, or service agreements:

  • Arc-flash testing of equipment and protection
  • Tests or modeling of grounding configurations
  • Downed-conductor tests and other tests of energized objects
  • Forensics and material analysis of equipment failures
  • Custom tests of PPE, tools, or safety-related technologies

Other Programs

EPRI research related to distribution safety is found in several other areas.

Program 1: Power Quality

MyPQ | P1 | portfolio

Program 1 is responsible for stray voltage and contact voltage investigations. These are important issues for public safety. This includes urban scenarios as well as swimming pool and other shock hazards to the public. See here for an update on recent research. strayvoltage.epri.com is an important resource.

Program 60: Electric and Magnetic Fields and Radio-Frequency Health Assessment and Safety

P60 | portfolio

This program considers environmental health and safety issues related to public and worker exposure to electric and magnetic field (EMF) and radio frequency (RF) environments associated with electric power system infrastructure.

Program 62: Occupational Health and Safety

P62 | portfolio

EPRI’s occupational health and safety research produces actionable tools and insights aligned with the pressing challenges articulated by EPRI members in conjunction with thought-leadership initiatives of EPRI staff. Research results from this program are relevant to utilities globally.

Program 180: Distribution Systems

Equipment failures can often pose safety risks. In both the P180.001 Overhead and P180.002 Underground projects, the fundamental deterioration and failure modes of equipment are evaluated.

The P180.002 Underground project is also covering issues with manhole explosions from flammable gases and faults. See here.


Last modified September 24, 2022