SAMLE JOB SAFETY ANALYSIS POWER UTILITY
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G4 ENGINEERING CONSULTANTS INTERNATIONAL INC
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National Tool & Engineering Institute
Renewable Energy Efficiency Technology Level 4
Apply Occupational Health & Safety Regulations, codes and
Practices in the Work Place (ETERNE0072B)
Job Task Analysis for Changing of Defective Insulator on 138 kV
Transmission Tie line – Duhaney to Tredegar
Names: Donovan A. Moore
Date: May 15, 2019
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Table of Contents
OVERVIEW .................................................................................................................................................... 3
Situational Background/Scenario.............................................................................................................. 3
Purpose ..................................................................................................................................................... 4
Scope/Limitations ..................................................................................................................................... 7
INTRODUCTION .......................................................................................................................................... 15
GENERAL SAFETY PROCEDURE/SAFE WORK PRACTICES............................................................................. 3
SPECIFIC ACTIVITIES/WORK PROCEDURES .................................................................................................. 3
Roles and Responsibilities ......................................................................................................................... 8
Preparatory Activities................................................................................................................................ 3
Switching and Earthing Procedures ......................................................................................................... 4
Execution of Corrective Works.................................................................................................................. 3
Closure of Works for Safe Re-Energized line ............................................................................................ 4
Restoration of Line Section to Grid ........................................................................................................... 4
IDENTIFICATION OF HAZARDS, RISKS AND CONTROL MEASURES ............................................................. 3
DEVELOPMENT OF RISK REGISTER ............................................................................................................... 3
CONCLUSION ................................................................................................................................................ 3
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OVERVIEW
Situational Background/Scenario *
G4 Engineering Consultants have been apprised by the Management of JPS that on April
the 25th, 2019, an insulator flash over occurred on Tower 19, approximately 5.45 km from the
Duhaney Substation, in the hill range overlooking the Caymanas plane. SCADA system
indicated phase to phase faults magnitude of only 650 Amps for a short duration of 0.0005
microseconds; a condition which was not of sufficient magnitude and duration to initiate relay
protection mechanisms. However, the incident resulted a damaged insulator on one phase of the
3 phase transmission line Star 138kV system between Duhaney and Tredegar. The insulator
indicated surface damage, suspected by unknown causes (which could be appropriately attributed
to an aged di-electric).
Based on its contact with Power Utility firm, G4 Engineering Consultants were engaged
to effect replacement to the damaged item in accordance with Engineering Design, Transmission
& Distribution (T&D) Standards, and related Safety & Work Procedure Standards, relevant to
the corrective maintenance process. Further, the Management of JPS, (headed by Board
chairman, Dr Lunan), required that a comprehensive Job Analysis be documented and presented
before execution. The purpose of this documentation was to test the readiness of G4 Consultants
regarding its level of knowledge, technical capability and capacity to operate within compliance.
Regardless, the existing condition was to be treated as urgent for repairs, as the
compromised insulation condition could likely escalate if left un-attended. This tie line is
essential for restoration within the next three (3) to five (5) days as typical load profile indicate
that demand conditions within the Kingston Metropolitan area will require this circuit to be in
tact as a means of supply both MVAs and MVARs to be imported from Old Harbour into
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Duhaney via Tredegar. The safe restoration of this line is required for ensuring system stability
and supply reliability over the next few days to come, and beyond.
* The actual scenario above is purely fictitious and was generated to inspire creative
thought in depicting a real-world condition, that would help to enrich the context for response to
an assignment question, and the interactive discussion/presentation to follow.
Purpose
This document shall seek to create a comprehensive Job Safety Analysis for the
Corrective maintenance/repair activities for replacing a damaged insulator on the Duhaney to
Tredegar 138 kV Transmission line on the JPS Power Grid. As a prerequisite for achieving the
stated intent, the required job processes and procedures, necessary for executing the work
activity shall be thoroughly outlined in the document. The document will necessarily identify all
the risks associated with the job, and how such risks can be appropriately managed.
Consequently, a Risk Registry will be included as an informational source for personnel,
practitioners, reviewers and other interested parties to reference in accordance with their
respective needs.
Scope/limitations
The core of the substance in this document, namely, the Job Analysis content, and all its
components shall be understood as only pertaining to the steps required to safely execute the
work for the damaged insulator in question, as described above. Whilst general principles can be
applied to similar job activities of insulation replacement on the T&D System at the transmission
level, the Job Analysis herein contained is specifically for the job described for the scenario
depicted.
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INTRODUCTION
This Job Safety Analysis document shall provide a comprehensive view of the approach,
scope and purpose of the job/tasks to be undertaken, and all the relevant safety standards and
requirements to ensure that all personnel are protected from undue exposure to hazards that may
exist within the specific work environment. The documentation will highlight the roles and
responsibilities of all assigned personnel on the job, pertaining to the activity to be undertaken,
and will further describe all the sequential processes and activities from the preparatory stage
(before actual execution) to the final stages and closure of the work operation.
The intent of such thorough documentation is to provide a meaningful sample for
appropriate adaptation and application to other assignments, similar or otherwise. The content of
any other Job Analysis shall be specific towards those jobs only. However, the next section to
follow provide extracted samples of general guidance that are broadly relevant to working on
Overhead Transmission lines.
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GENERAL SAFETY PROCEDURES/SAFE WORK PRACTICES
Situational Background/Scenario *
G4 Engineering Consultants have been apprised by the Management of JPS that on April
the 25th, 2019, an insulator flash over occurred on Tower 19, approximately 5.45 km from the
Duhaney Substation, in the hill range overlooking the Caymanas plain. SCADA system
indicated phase to phase faults magnitude of only 650 Amps for a short duration of 0.0005
microseconds; a condition which was not of sufficient magnitude and duration to initiate relay
protection mechanisms. However, the incident resulted a damaged insulator on one phase of the
3 phase transmission line Star 138kV system between Duhaney and Tredegar. The insulator
indicated surface damage, suspected by unknown causes (which could be appropriately attributed
to an aged di-electric).
SPECIFIC ACTIVITIES/WORK PROCEDURES
Roles & Responsibilities
In order to ensure that all relevant work personnel are fully aware, engaged and
adequately prepared to safely and effectively execute the Job Task to be undertaken, each
personnel and his/her role in the work activity must be identified. In addition, this step is
necessary to facilitate the clear lines of communication, interaction and consultations with all the
relevant personnel that will be involved with completing the assigned Job Task.
The following personnel along with their roles and responsibilities were identified as
important to delivering the specific job, to the required standards:
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DESCRIPTION OF PERSONNEL'S ROLES AND RESPONSIBILITIES FOR SPECIFIC TRANSMISSION LINE CORRECTIVE WORK
TABLE 1 - COMPONENT OF THE REQUIRED PREPARATION ACTIVITES FOR SAFE EXECUTION OF TASKS ON H.V. TRANSMISSION LINE
JOB
FUNCTION/TITLE
NATURE OF RESPONSIBILITY
NO. OF
PERSONNEL
Advanced Technical/Business
Qualfications/Professional
Certification. Over 15+ years of
progressive/distinguished
experience in Power Industry
Advanced Technical/Business
Qualfications/Professional
Certification. Over 10+ years of
progressive/distinguished
experience in Power Industry
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Engage, motivate and facilitate teamwork
based on standards of excellence, safe work
practices through policy enforcement,
consultations/wrok group discussions,
planning/coordination
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1. Coordinate work preparation activities 2.
Lead out in Tailbaord Discussions. 3. Provide
direct supervsion/instructions for tasks 4.
Control on-site hazards. 5. Take interventive
actions and manage communication
6-8
Obey instructions, Safety Standards, conform
to required work practices, conformance to
safety requirements, hazard control
procedures/system and ensure execution of
tasks/sub-tasks to avoid all injuries/danger
to self and fellow team-members
Technical/Academic Qualifications
at Undergraduate Degree/NVQJ
Level 5. At least five (5) years of
experience in Power Systems
Operations & Mtce. D2 - D3, T1-T2
Switching Authorization
Diploma/Assoc Degree/NVQJ Level
4 Technical Qualifications. At least
three (3) years of experience as a
Competent Staff. Specialized
JM/LM Training up to Grade A, Red
Seal or JM/LM Level 1. T1 - T3
Switching Authorization
Trained and Certified competent
Line Personnel, with High School
Diploma/5 ordinary level subjects
(preferably, NVQJ-Level 2 -3).
Authorization to switch at D1 - D3,
T1 desirable
Define Overarching Safety Policy, Develop Corporate
Strategy for Risk Management, Oversee
conformance to Legal/Regulatory Standards
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Director of T& D
Grid Operations
Implement framework for Technical Standards
conformance in Transmission & Distribution
portfolio, in accordance with firm's Safety Policies,
and Corporate Risk Mgt. Stategies. Provide general
managemnt oversight to work processes and
resource allocations
1
Manage assigned project and operational
deliverables, verify and pre-approve work resources,
Enforce conformance to Job Safety & Work Parctices
Supervisor/Leadman
- (Red Seal/JM-LM 1)
Coordinate assigned work/field activities in
conformity to established standards, through
adherance to the highest levels of Safety practices to
ensure full control of hazards and total prevention of
accidents on the job
Line Technician(s)
Execute assigned tasks to appropriate standards,
whilst adhering to safety rules/guidelines,
instructions and procedures, to prevent injury to self
and fellow team members
REQUIREMENT OF
TECHNICAL STATUS
Create the necessary business,
legal/contractual frameworks both from a
business & engineering standpoint, through
high level application of existing and
immergent industry standards/trends
Ensure adequete provisions of resources for
works standards, hazard/risk mitigation.
Provide Approvals for Job-Site Acess,
Outage/Live Line Work Plans, Permission to
Work (PTW) and contingencies
Chief Technical
Officer
Operations Manager
- TLM
ROLES FOR SPECFIC JOB TASK
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Preparatory Activities
In order to ensure that all relevant work personnel are fully aware, engaged and
adequately prepared to safely and effectively execute the Job Task to be undertaken, each
personnel and his/her role in the work activity must be identified. In addition, this step is
necessary to facilitate the clear lines of communication, interaction and consultations with all the
relevant personnel that will be involved with completing the assigned Job Task.
The Preparatory processes will be sub-divided in two (2) components/stages; Stage 1 –
Planning of Standards, Procedures & Safety Conformance, and Stage 2 – Planning of Resource
Requirements & Job Task Delivery. Both related stages are highlighted in the respective lists
below:
STAGE 1 PREPARATION
Under Stage 1 of the preparation for execution, the actions and decisions outlined must
be carried out before resources are committed and prior to actual work on the transmission
system. These include (but are not necessarily limited to):
1. Clear description on the nature of the work(s) to be done
2. Identification of all hazards and associated risks that may exist, or may arise
3. Discussion and consultation with JPS System Control & Planning Department– the
ultimate Technical Controllers of the Power System’s Grid
a. This communication would include request for approval of line section deenergization (if an outage is required) or request for use of Hot Stick/Live
Line Method (if working on the line section in an energised state is required)
b. Approval would be granted on technical considerations such as Customer’s
Reliability and System/Power Grid Stability
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c. The Applicable Information Technology Software (or otherwise manually
prepared forms) would be accessed and the essential details for the work to be
carried out placed in the forms. The completed form(s) with any necessary
attachments/data sheets would be submitted by some senior staff personnel at
the Transmission Line Maintenance (TLM) level. (Please note that if JPS
were to outsource this technical business operations component to a capable
Engineering firm, as mentioned in the scenario, the request would be
submitted by a person of equivalent rank/seniority, such as a
Supervisory/Lead personnel and/or an Operations/Maintenance Manager).
4. Planning/Work Team Meeting to discuss work procedures, hazards risks and safety,
pre-work responsibilities (who is responsible to do and get what), and on-site
responsibilities
a. Included here is specific instructions, special pre-cautions to work team
members
b. Accommodations must be given for staff interaction, feedback and request for
clarifications
5. Verification of Switching device location, identification numbers and operating
conditions/status
6. Emergency procedures – Plans and Contingencies for any undue exposures to hazards
causing accidents and injury. This will include First Aid Response, Emergency
extraction, rescue and transportation for medical treatment
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7. Work Environment control – Access Restrictions/Allowance, Limitations of Access,
Defined Work Zone(s), steps to mitigate environmental impact (if any).Site
mapping/layout with established boundaries
STAGE 2 PREPARATION
Under Stage 1 of the preparation for execution, the actions and decisions outlined must
be carried out before resources are committed and prior to actual work on the transmission
system. These include (but are not necessarily limited to):
Following the completion (or advanced development) of issues addressed in STAGE 1
are obtained, Stage 2 Preparation would include actions/decisions such as:
1. Determination of the tools, equipment, vehicles/machinery, Safety control devices,
protective equipment, administrative controls and all other resources are made ready
for the job to be carried out
2. Identification and notification of actual work team members, that must include an
Authorized Person(s), Competent Persons and Qualified Persons, with the requisite
training, credentials, knowledge, certification and competences to do the job
effectively and safely
3. Confirmed Work dates and resources based on all necessary approvals for works at
Departmental, System Control/Grid Operations and Corporate levels of the Power
Utility Firm.
4. Mobilization plans to work site, with plans for ample on-the-site preparations before
any work is done
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Switching & Earthing Procedures
There are two (2) choices of approach that can be taken to safely execute the corrective
works on the transmission line in question: (1) De-Energization and shorting to earth of the line
and (2) Use of a Live Line Method (Hot stick/Live Line Tools, Insulating/Rubber Gloves or
Barehanded/Equal-potential). However, this Job Safety Analysis documentation, shall select to
use the De-Energized Work Method (1), to safely complete the task of changing the defective
insulator. For this method chosen, the applicable hazard control measures that will be applied as
shown in the modified Hierarchy of Controls diagram shown here:
Considering the circuit diagram below, the schematic shall be used to provide a sequence
of steps for application of the De-Energization Method. This is known as a Switching Order.
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197/9-151
197/9-830
197/9-837
197/9-839
TREDEGAR S/S
197/9-106
197/-/-/9-537
20/9-739
20/9-730
20/9-737
DUHANEY S/S
SCHEMATIC DIAGRAM: SECTION OF JPS GRID –
TRANSMISSION TIE LINE BETWEEN DUHANEY & TREDEGAR
SUB-STATIONS
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Steps for Application of De-Energized Circuit Method
These are the steps for de-energising, isolating and grounding the 138 kV Transmission
Tie Line between Duhaney and Tredegar Sub-stations, on the JPS Electric Grid:
AT TREDEGAR
(1) Confirm that By-Pass switch, 197/8-838 (not shown in the diagram) is in the Open
Position
(2) Trip Circuit Breaker 197/9-830, and confirm the breaker indicates open
(3) Confirm that By-Pass switch 197/9-539 (not shown in schematic) is in the Open
Position
(4) Trip Bus Tie Breaker 197/9-530, and conform the breaker is indicating open
(5) Open Isolator 197/9-539
(6) Open Bus Breaker Isolator 197/9-839
AT DUHANEY
(7) Confirm that By-Pass switch (not shown) is in the Open Position
(8) Trip Circuit Breaker 20/9-730, and confirm the breaker indicates open
(9) Open 20/9-739 (looking away from the bus/towards the line)
(10)
Open Tie Line Isolator Switch 197/9-151 (Note an interlocking
device/mechanism may exist that will prevent closing earth switch 197/9 – 106)
(11)
Test/Buzz Line for verification of De-Energized status
(12)
Close Earthing Switch 197/9-151
(13)
Apply Additional Short & Ground Equipment (of suitable fault current rating)
mid span away from work location/tower to be worked on)
(14)
Specify/Impose Physical Barriers on work space
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(15)
Issue Permit to Work Document from Authorized Personnel (in Charge of
Switching) to Competent Person (in Charge of Work)
Execution of Corrective Works
As should be expected no work shall proceed on any section of the Power Utility Grid
until the following conditions are met:
1. The decision is made at the Preparatory Stage, that the De-Energized Method (in this
particular case) is to be used, and all the necessary preparations to include resources,
notifications and approvals have been granted
2. The Switching Process as outlined in the section above regarding Method of Isolation
have been executed by an Authorized Person (a competent, technically
knowledgeable and trained/certified personnel who is given the authority in writing)
to coordinate the re-configuration/switching of the system/circuit, under the authority
of the System Control Department (the custodians of the JPS Electric Grid)
The steps below indicate the sequence of activities for doing the Corrective Work of
changing the damaged insulator:
(1) Transport Personnel, materials and tools to work site
(2) Set Up Work Site
a. Lay Out Tools/Equipment
b. Create barriers/Boundaries around established perimeter
c. Clean/prepare tools for use
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(3) Hold Tailboard Meeting on site
a. Assign roles (ideally agreed prior in preparation stage), identify person in
charge, designated climbers/aerial unit operators, ground men, Spotters/flag
men, First Aider
b. Discuss work procedure
c. Identify hazards and associated risks (as a formal process this entails
recording hazards/risks identified on appropriate instrument/forms
d. Discuss and agree on how to avoid hazards/mitigate risks
(4) Put required Controls in place and/or confirm that they are adequately in place
(5) Have each personnel sign on to the Tailboard document
(6) Issue Permit-to-Work/All clear to commence work
(7) Take up assumed/assign work positions and affix tools
(8) Remove old insulator (approach is dependent on tools applied and type of insulation
configuration being used)
(9) Replace new insulator
(10)
Inspect adjacent insulator conditions and determine need for change
(11)
Repeat steps (8) and steps (9) if necessary
(12)
Do quality control checks – item(s) properly anchored, insulator angle correct,
clearance between phases maintained, conductor at proper sag/tension
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Closure of Works for Safe Re-Energization
(1) Remove Tools, equipment, additional short and ground and personnel from line
section
(2) Sign of Tail Board Conference Document
(3) Cancel Permit-to-Work (and any other access/authorization documents)
(4) Give notification of Clearance-to-Energize line section to Authorized Person
(5) Proceed with re-energization steps
(6) Stand Clear for re-energization