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When does energized work begin?

The best way to answer this question is to review the two NFPA 70E articles 120 and 130.  Article 120, Establishing an Electrically Safe Work Condition, provides the Lockout/Tagout requirements necessary to provide an electrically safe work condition for the employee.  Article 130, Work Involving Electrical Hazards,  has section 130.2 that requires that (1) exposed energized conductors (or parts) be put into an Electrical Safe Working Condition if you are within the Limited Approach boundary or (2) the employee is interacting with equipment where circuit conductors (or parts) are not exposed but an increased likelihood of injury from exposure to arc flash hazard exists.

Limited Approach boundary is the approach limit from an exposed energized equipment within which a shock hazard exists.  For 480 volt equipment, this is 42 inches per Table 130.4(D).  So the rules are to place equipment in an electrically safe work condition if the worker is within this 42 inches unless the energized equipment is justified per section 130.4(A).

Per Section 110.1 the employer in charge must complete a Job Safety Plan which includes the following:

  • Description of the job and the individual tasks
  • Identification of the electrical hazards associated with each task
  • Conduct a shock assessment for tasks involving a shock hazard
  • Conduct an arc flash assessment for tasks involving an arc flash hazard

So, when do I need an Energized Work Permit and how is this different?  An energized work permit is required if the worker is performing work within the Restricted Approach Boundary.  Per section 130.4(A) this is 12 inches for a 480 volt system or the worker is interacting with equipment where a circuit conductor (or parts) are not exposed but an increased likelihood of injury from exposure to arc flash hazard exists.

Similar to the job safety plan, the energized work permit has the same requirements as above and the additional requirement of “justification for why the work must be performed in an energized condition”.  In both cases, one is required to conduct both a shock and arc flash hazard assessment.

Hopefully, this answers the question of when energized work begins or at least provides the requirements while working around electrical equipment.

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Electrical Hazard Awareness

Electrical hazards on the job are more common then most people realize. Workers are exposed daily to electrical energy and many are unaware of the potential electrical hazards making them more vulnerable to the danger of electrocution. According to OSHA there are nearly 350 on the job electrical related deaths every year.

To help workers stay safe they need to understand the most common causes of electrical injuries and deaths listed by OSHA.

Generators, often used on construction sites are powered by gasoline or diesel to turn an alternator to produce electricity. Generators can be extremely dangerous if not used properly. They produce carbon monoxide a odorless gas that can cause headaches, loss of consciousness and even death if inhaled. OSHA states that generators should be used outdoors in a location where the exhaust gases cannot enter a home or building. Good ventilation is the key to operating a generator safely.

Extension cords can cause on the job injuries if the cord is worn and wires become exposed. extension cords that are not three-wire type or have been modified are not designated for hard use and can increase the risk of electrical shock. Only use extension cords that have been approved by a nationally recognized testing laboratory.

Worn electrical equipment can cause insulation breaks, short-circuits and exposed wires. in addition according to OSHA, if the equipment lacks ground fault protection it can cause a ground-fault that can send electrical current through a workers body. OSHA suggests using ground-fault interrupters on all 120-volt, single-phase, 15 and 2-ampere receptacles that are not on an existing buildings permanent wiring. In addition, using double insulated electrical tools and inspecting all equipment before use. If a tool has missing prongs, frayed cords or cracked casings, remove it from use.

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NFPA 70E 2018 CHANGES

What’s new?

The 2018 edition of NFPA 70E continues in how stakeholders evaluate electrical risk — so that owners, managers, and employees can work together to ensure an electrically safe working area and comply with OSHA 1910 Subpart S and OSHA 1926 Subpart K.

This article covers the major changes within NFPA 70E 2018 version. It does not contain every change, and some language is paraphrased due to space limitations. Since the final document has not yet been formally approved, additional changes are possible before publication. Therefore, refer to the final approved version once it is published.

Global Changes

  • “Accident/Accidental” with “Incident/Incidental”
  • “Hazard Analysis” with “Risk Assessment”
  • “Short Circuit Current” with “Available Fault Current”
  • Insertion of “exposed” in front of “energized conductors and circuit parts”
  • Provide dual units of both calories and joules

Article 90 Introduction

90.4 Organization: This section was deleted because it contained the same information as the table of contents.

90.5(D) Informative Annexes: This new addition emphasizes that nonmandatory information is in the informative annexes, which are not part of the standard’s requirements.

Article 100 Definitions

The following definitions have been revised.

Accessible, Readily: The words “take,” “other than keys” and “under to” were added: …ready access is requisite to take actions such as the use tools (other than keys), to climb over or under to remove…

Arc Flash Hazard: The term “dangerous condition” was changed to “a source of possible injury or damage to health.”

Boundary, Arc Flash: The revised definition uses the term “approach limit” rather than “at a distance” and no longer uses the term “second degree burn” but instead “at which incident energy equals 1.2 cal/cm2.” The revised informational note references the Stoll skin burn injury model.

Electrical Hazard: The word “arc” was added to blast for “arc blast.”

Electrical Safety: The word “recognizing” hazards was changed to “identifying” hazards. The text “so that hazards do not cause injury or death” was changed to: “to reduce the risk associated with those hazards.”

Electrically Safe Work Condition: “Ensure” was changed to “verify,” and the text regarding grounding was changed from “temporary protective grounding equipment has been applied” to “temporarily grounded for personnel protection.”

Qualified Person: “Identify and avoid the hazards involved” was changed to “identify the hazards and reduce the associated risk.”

The following definitions are new.

Electrical Safety Program: A documented system consisting of electrical safety principles, policies, procedures and processes that directs activities appropriate for the risk associated with electrical hazards.

Fault Current: The amount of current delivered at a point on the system during a short-circuit condition.

Fault Current, Available: The largest amount of current capable of being delivered at a point on the system during a short-circuit condition.

Maintenance, Condition of: The state of the electrical equipment considering the manufacturers’ instructions, manufacturers’ recommendations and applicable industry codes, standards and recommended practices.

Working Distance: The distance between a person’s face and chest area and a prospective arc source.

 

Article 105 Application of Safety-Related Work Practices and Procedures

The words “and Procedures” were added to the title of this article.

105.3 Responsibility: This section was revised and subdivided into “Employer Responsibility” and “Employee Responsibility.”

105.3(A) Employer Responsibility: This new text requires that safety-related work practices and procedures required by this standard shall be established, documented and implemented by the employer. In addition, the employer shall provide training in safety-related work practices and procedures for employees.

105.3(B) Employee Responsibility: This new text requires the employee to comply with the safety-related work practices and procedures provided by the employer.

105.4 Priority: This new addition emphasizes that hazard elimination shall be the first priority in the implementation of safety-related work practices.

 

Article 110 General Requirements for Electrical Safety-Related Work Practices

110.1 Electrical Safety Program

110.1(B) Inspection: This new addition requires that “the electrical safety program includes elements to verify that newly installed or modified electrical equipment or systems have been inspected to comply with applicable installation codes and standards prior to being placed into service.”

110.1(H) Risk Assessment Procedure: In addition to 110.1(H)(1), new parts 110.1(H)(2) and (H)(3) were added.

110.1(H)(2) Human Error: This addresses the potential for human error and its negative consequences on people, processes, the work environment and equipment.

110.1(H)(3) Hierarchy of Risk Control Methods: This was moved from an informational note to become part of the mandatory language.

110.1(I) Job Safety Planning and Job Briefing: “Job Safety Planning” was added to the title, and it was divided into two parts: (1) Job Safety Planning and (2) Job Briefing. Some information previously included as part of Job Briefing was moved to Job Safety Planning and is provided in a list format.

110.1(J) Incident Investigation: This new section requires the electrical safety program to include elements to investigate electrical incidents.

110.1(K) Auditing: The words “Electrical Safety” were deleted from the title. The word “Audit” was added to (1) Electrical Safety Program Audit and (2) Field Work Audit and (3) Lockout/Tagout Program and Procedure Audit.

110.1(K)(3) Lockout/Tagout Program and Procedure Audit: This new addition is based on the relocated 120.2(C)(3). Also, the audit shall be designed to identify and correct deficiencies specified in the following:

(1) The lockout/tagout (LOTO) program and procedure

(2) The LOTO training

(3) Worker execution of the LOTO procedure

110.2(C) Emergency Response Training

110.2(C)(2)(d) First Aid, Emergency Response and Resuscitation: The reference to refresher training occurring “annually” was changed to “at a frequency that satisfies the requirements of the certifying body.”

110.3 Host and Contract Employer’s Responsibilities

110.3(A)(2) Host Employer Responsibilities: An informational note was added that provides examples of a host employer, which can include the owner or their designee, construction manager, general contractor or employer.

110.4 Test Instruments and Equipment: The section title was changed from “Use of Electrical Equipment.” Language referring to the limited approach boundary and electrical hazards was deleted.

 

Article 120 Establishing an Electrically Safe Work Condition

This article was reorganized to provide a more logical sequence for the overall process. It is now organized into the following sections:

  • 120.1 Lockout/Tagout Program
  • 120.2 Lockout/Tagout Principles
  • 120.3 Lockout/Tagout Equipment
  • 120.4 Lockout/Tagout Procedures
  • 120.5 Process for Establishing and Verifying an Electrically Safe Work Condition

120.1 Lockout/Tagout Program

120.1(A) General: This section states that “Each employer shall establish, document and implement a lockout/tagout program.” The LOTO program and procedures shall also incorporate the following:

(1) Be applicable to the experience and training of the workers and conditions in the workplace

(2) Meet the requirements of Article 120

(3) Apply to fixed, permanently installed equipment, temporarily installed equipment and portable equipment

120.1(B) Employer Responsibilities: As part of the LOTO program, Section 120.1(B) states the employer shall be responsible for the following:

(1) Providing the equipment necessary to execute the lockout/tagout procedures

(2) Providing LOTO training to workers in accordance with 110.2

(3) Auditing the LOTO program in accordance with 110.1

(4) Auditing execution of the LOTO program in accordance with 110.1

120.2 Lockout/Tagout Principles

120.2(A) General: This states the requirements of Article 120 must be met in order to have an electrically safe work condition.

120.2(B) Employee Involvement: This requires that “each person who could be exposed directly or indirectly to a source of electrical energy shall be involved in the lockout/tagout process.”

120.2(C) Lockout/Tagout Procedure: Previously named “Plan,” this language was relocated from 120.2(B)(5). The language “A lockout/tagout procedure” shall be developed and “suitable documentation including” up-to-date drawings and diagrams was added.

120.3 Lockout/Tagout Equipment: This is based on relocating 120.2(E) and covers the requirements of lock application, LOTO device, lockout device and tagout device.

120.4 Lockout/Tagout Procedures: This section is derived from relocating other sections.

120.5 Process for Establishing and Verifying an Electrically Safe Work Condition: This was previously 120.1. It was relocated and the title was revised. Two additional steps were added to the process. They include:

(4) Release stored electrical energy

(5) Release or block stored mechanical energy

 

Article 130 Work Involving Electrical Hazards

130.1(2) General: The text “The electrical safety-related work practices” is now “Requirements for work involving electrical hazards such as the electrical safety-related work practices, assessments, precautions and procedures” when an electrically safe work condition cannot be established.

130.2 Electrically Safe Work Condition: New text “operating at voltages equal to or greater than 50 volts” was added.

Exception: The disconnecting means or isolating element exception was deleted.

130.2 (A)(4) Normal Operating Conditions: A sixth condition for normal operation was added: “The equipment is used in accordance with instructions included in the listing and labeling and in accordance with manufacturer’s instructions.”

130.2 (B) Energized Electrical Work Permit

130.2(B)(1) When Required: The text “when energized work is permitted” was changed to “when work is performed as permitted” in accordance with 130.2(A). The reference to “energized” was deleted.

130.4 Shock Risk Assessment: This section was renamed and reorganized.

130.4(A) General: This section lists the revised requirements of a shock risk assessment, which includes:

(1) To identify shock hazards

(2) To estimate the likelihood of occurrence of injury or damage to health and the potential severity of injury or damage to health

(3) To determine if additional protective measures are required, including the use of PPE

130.4(B) Additional Protective Measures: New language refers to the hierarchy of risk control if additional protective measures are required. “When the additional protective measures include the use of PPE, the following items shall be determined:”

(1) The voltage to which personnel will be exposed

(2) The boundary requirements

(3) The personal and other protective equipment required by this standard to protect against the shock hazard

130.4(C) Documentation: The results of the shock risk assessment shall be documented.

Table 130.4(C)(a) and Table 130.4(C)(b): The title of this table now includes “Shock Protection” to describe the Approach Boundaries and includes the word “exposed” when describing energized electrical conductors. There are minor changes to a few Restricted Approach Boundaries. The minimum voltage for Table 130.4(C)(b) was changed from 100 volts to 50 volts.

130.5 Arc Flash Risk Assessment: This section was reorganized as follows.

130.5(A) General

130.5(B) Estimate of Likelihood and Severity

130.5(C) Additional Protective Measures

130.5(D) Documentation

130.5(E) Arc Flash Boundary

130.5(F) Arc Flash PPE

130.5(G) Incident Energy Analysis Method

130.5(H) Equipment Labeling

130.5(A) General: This section lists three items that are part of the arc flash risk assessment:

(1) To identify arc flash hazards

(2) To estimate the likelihood of occurrence of injury or damage to health and the potential severity of injury or damage to health

(3) To determine if additional protective measures are required, including the use of PPE

130.5(B) Estimate of Likelihood and Severity: This new section requires taking into account “the design of electrical equipment, including its overcurrent protective device and its operating time.” The electrical equipment operating conditions and the condition of maintenance shall also be considered.

130.5(C) Additional Protective Measures: This new section defines a requirement that if additional protective measures are required that include the use of PPE based on the hierarchy of risk control, three items shall be determined:

(1) Appropriate safety-related work practices

(2) The arc flash boundary

(3) The PPE to be used within the arc flash boundary

Table 130.5(C) Estimate of the Likelihood of Occurrence of an Arc Flash Incident for AC and DC Systems: “Shall be permitted to be used to estimate the likelihood of occurrence of an arc flash event to determine if additional protective measures are required.” This table was formerly Table 130.7(C)(15)(A)(a).

The term “Arc Flash PPE Required,” Yes or No was changed to “Likelihood of Occurrence” Yes or No.

Previously five conditions had to be met for “normal” equipment condition. A sixth has been added: “The equipment is used in accordance with instruction included in the listing and labeling and in accordance with manufacturer’s instructions.”

Table 130.5(G) Selection of Arc-Rated Clothing and other PPE When the Incident Energy Analysis Method is Used: This new table has been added and “shall be permitted to be used with the incident energy analysis method for selecting arc flash PPE.” The table is derived from information previously located in Annex Table H.3(b).

130.7 Personal and Other Protective Equipment

130.7(A) Informational Note 3: This note—which stated when the incident energy exceeds 40 cal/cm2 at the working distance, greater emphasis may be necessary with respect to de-energizing—has been deleted. Instead, a greater emphasis should always be placed on de-energizing, not just above 40 cal/cm2.

130.7(C)(7) Hand and Arm Protection: Three conditions have been added where using rubber insulating gloves without leather protectors is permitted:

(1) There shall be no activity performed that risks cutting or damaging the glove.

(2) The rubber insulating gloves shall be electrically retested before reuse.

(3) The voltage rating of the rubber insulating gloves shall be reduced by 50 percent for class 00 and by one whole class for classes 0 through 4.

130.7(C)(14) Standards for Personal Protective Equipment: (a) General: The reference to standards listed in Table 130.7(C)(14) which contains specific industry standards for PPE has been replaced with “PPE shall conform to applicable state, federal, or local codes and standards.” The list of standards is now in an informational note as examples.

(b) Conformity Assessment: This section requires that “All suppliers and manufactures of PPE shall demonstrate conformity with an appropriate product standard by one of the following methods.”

(1) Self-declaration with a Supplier’s Declaration of Conformity

(2) Self-declaration under a registered quality management system and product testing by an accredited laboratory and Suppliers Declaration of Conformity

(3) Certification by an accredited, independent, third-party certification organization

130.7(E)(1) Safety Signs and Tags: References to specific standards have been deleted and instead reference is made to “applicable state, federal or local codes and standards.”

205.3 General Maintenance Requirements: The new Informational Note No. 2 states that “Noncontact diagnostic methods in addition to scheduled maintenance activities of electrical equipment can assist in the identification of electrical anomalies.”

350.4 Electrical Safety Authority (ESA): This new section permits each laboratory or R&D System application to assign an ESA to ensure the use of appropriate electrical safety-related work practices and controls.

The 2018 edition is almost here, and then the next countdown will begin—for the 2021 edition. Change is certainly a guaranteed constant.

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What’s the difference between the Main and System Bonding Jumper?

The main bonding jumper and the system bonding jumper perform the same function.  And that is to connect the Equipment Grounding Conductor (bare or green wire) to the grounded neutral conductor at either at the transformer location (separately derive system) or the first panel supplied by the transformer.

Although they perform the same function, the two terms are used to distinguish themselves from each other.  The main bonding jumper is installed at the incoming service equipment.  The system bonding jumper is any bonding jumper in a downstream separately derived system (transformer).

For example if the facility receives 480 volts at the incoming service, there will be one main bonding jumper.  And if the facility has three downstream transformers (480 volt DELTA to 208 volt WYE), each transformer (or first panelboard) will have the system bonding jumper.

Additional info:

In a grounded system, the primary function of the main bonding jumper and the system bonding jumper is to create the path for the ground fault current between the Equipment Grounding Conductor and the grounded (neutral) conductor.

Table 250.102(C)(1) (which looks really familiar with Table 250.66 for sizing grounding electrode conductors) is used to establish the minimum size of the main and system bonding jumpers. Unlike the grounding electrode conductor, which carries current to the earth (ground) via the connection to a grounding electrode like the water pipe or concrete encased electrode, the main and system bonding jumpers are placed directly in the supply side ground fault current path.