High Voltage Safe Working Procedures
3.2 The Inherent Dangers and Avoidance of Disastrous Consequences What is risk?
IMO a : T a a
a a . (MSC C 1023/MEPC C 392).
Here, the frequency is ( . ., a ) a
a a .
In other words, risk has two components:
Likelihood of occurrence Severity of the consequences.
A hazard is a substance, situation or practice that has the potential to cause harm. Briefly, what we are concerned with, therefore, is:
The identification of hazards
The assessment of the risks associated with those hazards
The application of controls to reduce the risks that are deemed intolerable The monitoring of the effectiveness of the controls
High Voltage Safe Working Procedures
The controls may be applied either to reduce the likelihood of occurrence of an adverse event, or to reduce the severity of the consequences.
The risks we are concerned with are those which are reasonably foreseeable and relate to:
1. The health and safety of all those who are directly or indirectly involved in the activity, or who may be otherwise affected
2. The property of the company and others 3. The environment
This process includes the following elements:
1. Risk assessment
2. Work Permits and Checklist 3. Tool Box Meetings
3.2.1 Risk Assessment
T a a a a a
risks associated with shipboard operations and take risk control measures to reduce the risk to an acceptable level or As Low as Reasonably Practicable (ALARP) to create awareness about the safety, health and environment issues prior to conducting a task.
A risk assessment should be performed before the work is started. Risk assessment is required and should be carried out prior to any activity where the following conditions can occur and any operations which present risk to people, property and environment including:
1. Routine work.
2. Breakdown Maintenance
3. Maintenance / immobilization of critical equipment.
4. When operational conditions change i.e., change of equipment, crew, etc.
Chapter 3
2. Be compliant with ISM Chapter 1.2.2.2 that the company should assess all identified risks in its ships, for its personnel and the environment and establish appropriate safeguards.
A , a A G R A ent in
S O a (Published by the International Association of Classification Societies (IACS) - Dated: 26/03/2004 - Revision: 0)
Quote
The best safeguard against accidents is a genuine safety culture - awareness and constant vigilance on the part of all those involved, and the establishment of safety as a permanent and natural feature of organizational decision-making .
Unquote
The process is carried out by carrying out the following steps:
1. Identifying and analysing potential hazards and the assessment of risk.
2. Action plan listing accident prevention and risk reducing measures in order or priority.
3. Execution of plan.
4. Evaluation of results.
High Voltage Safe Working Procedures
Identify the processes
Apply the lessons learned
Evaluate and analyse performance of
processes and controls
Define and implement new
or additional controls Identify and
assess the risk associated
with the process
Monitor changing conditions and
practices
Identify the hazards
associated with the processes
Develop and implement performance measurement
criteria
Identify and evaluate existing
controls
Figure 3.1 – The Risk Management Flow Chart
Chapter 3
3.2.2 Tool Box Meeting
A toolbox meeting is a meeting held by the authorised person and competent persons designated to complete the task, at the workplace to discuss the hazards that may be encountered during that task and the procedures that are in place to successfully manage any hazards. It is a process of continuous hazard awareness.
A toolbox meeting should be held prior to carrying out any safety critical tasks, complicated operation or at any time it is felt necessary.
If the task at hand requires a risk assessment, then a risk assessment shall be initiated by the authorised person prior to the toolbox meeting.
The risk assessment will then be discussed at the toolbox meeting.
The toolbox meeting should include all personnel likely to be engaged in the operation or whose work may be affected by it.
3.2.2.1 Toolbox Meeting Agenda
The following points will be discussed during toolbox meetings:
The operation at hand and how it will be conducted.
Discuss the relevant risk assessment.
Identify hazards and control measures to mitigate them.
The contingency measures to be taken in case of a failure or loss of a control.
The individual responsibilities for the operation, i.e. who does what.
All persons involved in the task should be satisfied that the risks have been reduced to an acceptable level or as low as reasonably practicable before the task commences.
Below are examples of some questions that may be raised when discussing such operational matters: If the answer is a , a
measures should be taken before starting the job.
High Voltage Safe Working Procedures
1. Is there a risk of slipping, tripping, falling from a height or falling overboard?
2. Is there a risk of being struck by or against an object?
3. Is there a risk of being caught in, on, or between objects?
4. Is there any risk of lack of oxygen or exposure to toxic gases or hazardous substances?
5. Is there a risk of fire?
6. Is there a risk of electric shock?
7. Is there a risk of electric arc flash / arc blast?
8. Is there a risk due to excessive heat, cold, radiation, noise, rolling or pitching?
9. Is there a risk due to fatigue?
10. Is there a risk of pollution of any type?
11. Is there a risk due to poor lighting?
12. Are there any navigational risks involved?
3.2.3 High Voltage Electrical Risk Assessment Steps
1. Identify the electrical hazards associated with the task and the electrical system, or the electrical process involved (e.g., shock hazard or an arc flash hazard).
2. Identify the electrical work to be performed within the electrical system or process.
3. Define the possible failure modes that result in exposure to electrical hazards and the potential harm.
4. Assess the severity of the potential injury from the electrical hazards.
5. Determine the likelihood of the occurrence for each hazard.
6. Define the level of risk for the associated hazard.
Chapter 3
The risk related to an identified hazard may be thought of as being composed of the severity of the injury and the likelihood of occurrence of that injury. There are five procedures which can be followed in order to carry out the risk management process as shown in Figure 3.2 below:
Figure 3.2 – Procedure for Risk Management
High Voltage Safe Working Procedures
3.2.4 Risk Assessment Forms
Description: DG No.6 Alternator Exciter and AVR Inspection / Repair Risk Assessment No.
E XXXX Department: Engineering
Stage 1 Preparations / Isolation
Hazard Area Consequence Initial
Risk Factor
Control Measures
Final Risk Accepta
ble
Reference Publications
Comments Live low
voltage control circuit
People, Assets
Environment, Reputation
Personal Injury, Electric shock
B4
Isolate all control supplies including heaters, use Lockout for Life (LOFL), post notices, Test and ensure that the circuit is dead (with a multimeter)
COSWP 3.12.7, 3.12.11
Unfamiliar with HV equipment
, breaker racking
out/in
People, Assets
Environment, Reputation
Electric shock, Personal Injury,
Mechanical Damage
C3
A trained person is to be in-charge, no excessive force to be applied on the breaker while racking it in / out. Follow
a e c .
Ensure complete familiarity with HV work procedures.
COSWP 20.12.2, 20.7, 20.14,
20.15
Live equipment
High Voltage
People, Assets
Environment, Reputation
Electric shock, Mechanical asset damage, death by
Electrocution
C4
Good discussion and planning, check that all instruments are working before starting the job, ensure that rubber matting is in place, rack out the DG isolation breaker to the fully withdrawn position and earth it, use HV gloves, test for dead bus bars / terminals with a HV test stick, use lock out for life / post notices.
Wrist watches or any jewellery should be removed, wear appropriate PPE / wear a HV boiler suit.
F e a e
instructions, earth the
COSWP 20.12.2, 20.7, 20.14,
20.15, 20.12.2
Chapter 3
Stage 1 Preparations / Isolation
Hazard Area Consequence
Initial Risk
Factor Control Measure Final Risk Acceptable
Reference Publications
Comments Unwanted
Personnel People Assets
Environment, Reputation
Personal Injury, Electric
shock C3
Restrict entry to the work space for any personal not included in the work scope of the area.
COSWP 3.12.11
Contractor
Unfamiliarity People Assets
Environment, Reputation
Personal Injury
C4
Discuss LSR, Discuss and follow risk assessment, any unsafe job to be stopped at any time, job to be monitored by the
aff.
COSWP 3.12
Ship Movement
People Assets
Environment, Reputation
Asset damage, Personal
injury
C4
Check the weather conditions before starting. Work should not be started in bad weather, Bridge to keep E/R informed about the weather conditions
COSWP 11.2, 11.8, 11.11,
11.12
Stage 2 Maintenance Sharp edges
on equipment People Assets
Environment, Reputation
Cuts / Personal
Injury D2
Wear gloves, the boiler suit sleeves must be fully rolled down, beware of sharp edges.
COSWP 8.9.1, 8.9.2, 3.12.1, 3.12.5
Tripping Hazard
People Assets
Environment, Reputation
Falling, Body injury
B4
Visual inspection of area before starting the work, Secure loose material / tools and clean up slippery surfaces before starting the job.
COSWP 23.2.1, 23.2.2,
23.2.5
Noise People Assets
Environment, Reputation
Damage to the
ears C3
Wear ear
protection COSWP 8.6,
18.22.10, 12.5.2, 12.7 Restricted
spaces
People Assets
Environment, Reputation
Cuts / wounds, trapped body
parts C3
Discuss restricted space entry procedures, wear gloves, boiler suit sleeves fully rolled down, do not be in a hurry
COSWP 20.2, 20.12, 8.9.2
Incorrect tools People Assets
Environment, Reputation
Personal injury, Mechanical damage to the
equipment
D3
Correct tools to be used, inspect / test tools before use,
F a e
instructions.
COSWP 3.12, 8.4.1, 8.4.2,
20.3
High Voltage Safe Working Procedures
Stage 2 Maintenance (continued)
Hazard Area Consequence
Initial Risk
Factor Control Measure Final Risk Acceptable
Reference Publications Comments Insufficient
Lighting People, Assets
Environment, Reputation
Hand injury, Personal
injury C4
Check the lighting before starting, 24V hand lamps and approved flash lights are to be used as required.
COSWP 3.12, 3.12.1
Chemicals / Using electro- cleaner
People, Assets
Environment Reputation
Burns, Personal
injury D3
Wear chemical- proof gloves, a face shield with a helmet and the body must be fully protected.
COSWP 8.7.1, 8.7.2,
21.5.5
Fatigue People, Assets
Environment, Reputation
Personal injury
C4
Ensure sufficient rest before the work, take regular breaks and drink sufficient water, follow the rest requirements.
COSWP 3.6, 3.6.2, 3.6.3,
3.12
Manual
Lifting People, Assets
Environment, Reputation
Back pain
B4
Use proper lifting techniques, ask for assistance if required, do not be in a hurry
COSWP 10.3.4, 10.4.9,
3.12.9
Accidental starting of the engine
People, Assets
Environment, Reputation
Trapped body part, damage
to the machinery
B4
Shut-off the engine starting air, use LOFL, release the air pressure on the engine side, keep
the engine
Standby in the Off condition, among other precautions and post notices.
COSWP 20.7, 20.12.2, 20.5
Lifting cooler/
Falling objects
People, Assets
Environment, Reputation
Personal injury, mechanical
damage B4
Check the
condition of all gear before use, do not stand / work
under the
suspended load
COSWP 8.5, 8.5.1, 8.5.3
Falling from
height People, Assets
Environment, Reputation
Broken body parts, personal injury
C4
Ensure that a safety harness is worn, secured to a strong point, inspect and secure the staging, a portable ladder is to be used.
COSWP 8.10.1, 8.10.2,
4.6.4
Chapter 3
Stage 2 Maintenance (continued)
Hazard Area Consequence Initial Risk
Factor Control Measure Final Risk Acceptable
Reference Publications
Comments Falling or
slipping People, Assets
Environment, Reputation
Broken body parts
C3
Wear a safety harness, a safety helmet with a chin strap on, secure the harness to an upper strong point, secure a portable ladder before use, keep
a person
standing by.
COSWP 8.10.1,
8.10.2
Residual
energy People, Assets
Environment, Reputation
Fatality, personal injury
B4
Once the circuit breaker is isolated, the CB in the HV room
should be
earthed to discharge any residual energy, lock the earth switch in the closed position and remove the key until work completed, Test the HV test sticks before commencing the work. Check all LV circuits and prove the circuit to be dead before starting the work.
COSWP 20.7, 20.14,
3.6
Stage 3 De-Isolation Metal
tools left inside
People, Assets
Environment, Reputation
Electrical and mechanical
damage
C4
Use the
minimum
number of tools at a time, keep a track of the tools being used.
Carry out
inspection of the cabinet before and after by a minimum of two persons. Secure the tools by using lanyards.
COSWP 3.10.1, 27.13.1,
27.13.4
Identify the hazards and potential accidents e.g., a generator without regular maintenance.
A possible accident can be: loose connections ⇒ heating ⇒ explosion ⇒ fire! Define the frequency or the likelihood that an accident might happen, how often the hazard might lead to an accident: Rare (1) Unlikely (2) Possible (3) Likely (4) Probable (5). In the case of a
High Voltage Safe Working Procedures
Define the severity and consequences as to what kind of impact the hazard and potential accident would have. Negligible (1) Minor (2) Significant (3) Serious (4) Life threatening (5).
In case of a generator running without regular maintenance, the consequences of a loose connection could be just stopping of the generator, or a more serious explosion and fire; the consequences could be significant or serious so give it a score of (4).
CONSEQUENCE INCREASING LIKELYHOOD>>>
SEVERITY
People Asset Environment Reputation Never heard in
the Industry
Heard in the Industry
C* C** C***
No injury or health affected
No
damage No effect No
impairment A0 B0 C0 D0 E0
Slight injury or health is affected
Slight damage
Slight effect
Slight
impairment A1 B1 C1 D1 E1
Minor injury or health affected,
death
Minor damage
Minor effect
Minor
impairment A2 B2 C2 D2 E2
Major injury or health affected,
death
Moderate damage
Moderate effect
Moderate
Impairment A3 B3 C3 D3 E3
Permanent or total disability, $ loss
Major damage
Major effect
Major
Impairment A4 B4 C4 D4 E4
More than $ loss Maximum damage
Maximum effect
Maximum
impairment A5 B5 C5 D5 E5
Chapter 3
T a a a
designer and / or manufacturer. The following measures can be adopted to reduce risk:
Introduction of safe working procedures Executing work under supervision
Implementing permit-to-work systems
Provision and usage of additional safeguards Use of adequate personal protective equipment
Training users to follow safe and recommended procedures Reading operating / safety instructions and acting accordingly
When risk reduction measures have been executed, they must be evaluated in order to ensure that the measures taken were adequate for the purpose of reducing the risk to an appropriate level. This can be done by repeating the risk assessment process.