Job Safety Analysis-Preliminary Hazard Analysis-Failure mode and Effects Analysis- Hazard and Operability- Fault Tree Analysis- Event Tree Analysis Qualitative and Quantitative Risk Assessment- Checklist Analysis- Root cause analysis- What-If Analysis- and Hazard Identification and Risk Assessment

1. Unit-V
Hazard Identification
Techniques

2. Job Safety Analysis
Job Safety Analysis (JSA) is a process that helps
integrate accepted safety and health principles into a
particular task or job operation. The goal of a JSA is
to identify potential hazards associated with each step
of a job and recommend procedures to control or
prevent these hazards.
• Selecting the Job: Choose the job or task to be
analyzed.
• Breaking Down the Job: Divide the job into
individual steps.
• Identifying Potential Hazards: Determine the
hazards associated with each step.
• Determining Preventive Measures: Develop
measures to eliminate or reduce the hazards.

3. Preliminary Hazard Analysis
Preliminary Hazard Analysis (PHA) is a risk
assessment tool used in the early stages of system
design to identify and categorize potential hazards
associated with the operation of a proposed system,
process, or procedure. It’s a semi-quantitative
analysis that helps in:
• Identifying all potential hazards and accidental
events that may lead to an accident.
• Ranking the identified accidental
events according to their severity.
• Identifying required hazard controls and follow-up
actions.

4. • The PHA is often the first step in the system safety
process and can be developed using techniques
such as Failure Modes and Effects Analysis
(FMEA) and Energy Trace and Barrier Analysis
(ETBA). It’s typically performed by a
knowledgeable team and relies on expert judgment
to assess the significance of hazards and assign a
ranking to each situation.
• The process involves establishing a PHA team,
describing the system to be analyzed, collecting
risk information from previous systems, identifying
hazards, recording all findings, and noting that no

5. Failure mode and Effects Analysis
Failure Mode and Effects Analysis (FMEA) is a
systematic, step-by-step approach for identifying all
possible failures in a design, a manufacturing or
assembly process, or a product or service. It’s a
proactive tool used to anticipate potential problems
before they occur and to take corrective actions to
prevent them.
• Assemble a Cross-Functional Team: Gather a
diverse group of people with knowledge about the
system, product, or service.
• Define the Scope of the FMEA: Determine whether
it’s for a concept, system, design, process, or
service.

6. • Assign Severity, Occurrence, and Detection
Ratings: Rate the severity of the effects, the
frequency of occurrence, and the likelihood of
detection before failure occurs.
• Calculate the Risk Priority Number (RPN):
Multiply the severity, occurrence, and detection
ratings to get the RPN, which helps prioritize
the failure modes.
• Develop Action Plans: Identify actions to
reduce the RPN by addressing the most critical
failure modes first.
• Implement Actions and Reassess: Take the
necessary steps to mitigate risks and reassess
the system to ensure effectiveness.

7. Hazard and Operability
Hazard and Operability (HAZOP) is a structured and
systematic examination of a complex system, typically
a process facility, to identify potential hazards to
personnel, equipment, or the environment, as well as
operability problems that could affect operational
efficiency.
• Define the Scope: Clearly outline the boundaries of
the study.
• Select the Team: Assemble a multidisciplinary team
with various expertise.
• Gather Information: Collect all relevant information
on the process or system.
• Identify the Elements: Break down the process into

8. • Identify Potential Hazards and Operability Issues:
Discuss and record possible problems for each
element.
• Evaluate Risks: Assess the severity and likelihood of
identified hazards.
• Recommend Safeguards: Suggest measures to
mitigate or eliminate risks.
• Document Findings: Record all the hazards,
operability issues, and recommendations.
• Review and Update: Regularly revisit the HAZOP to
ensure it remains current and effective.
HAZOP is widely used in industries such as chemical,
pharmaceutical, oil and gas, and nuclear, where it helps
to proactively catch hazards and formulate risk mitigation
strategies during the planning or design stage of

9. Fault Tree Analysis
Fault Tree Analysis (FTA) is a risk analysis technique
used to determine the probability of a specific undesired
event within a system. This method uses a top-down,
deductive failure analysis that involves identifying many
potential causes of system failures.
• Define the Undesired Event: Clearly
specify the event that you want to
analyze, which should be significant and
measurable.
• Construct the Fault Tree: Create a
diagram that visually represents the
pathways to the top event from basic
events and intermediate events.
• Identify Contributing Factors: Determine
the basic and intermediate events that

10. • Calculate the Top Event Probability: Use the
probabilities of the contributing factors to
calculate the overall probability of the undesired
event.
• Evaluate the Results: Analyze the fault tree to
identify areas of highest risk and potential
improvements.
• Develop Mitigation Strategies: Propose actions
to reduce the risk of the top event occurring.
FTA is particularly useful in industries where
system failures can have significant
consequences, such as aerospace, nuclear
power, chemical processing, and automotive

11. Event Tree Analysis
Event Tree Analysis (ETA) is a forward, top-down,
logical modeling technique used in risk
assessment to explore the possible outcomes
following an initiating event. It’s particularly useful
for analyzing the effects of functioning or failed
systems given that an event has occurred.
• Define the Initiating Event: Identify and clearly
describe the event that starts the analysis.
• Develop the Event Tree: Create a branching
diagram that represents all possible paths from
the initiating event to the final outcomes.
• Identify Possible Outcomes: Determine all the
potential consequences that can result from the

12. • Assign Probabilities: Estimate the likelihood of
each branch of the event tree occurring.
• Calculate the Overall System Analysis: Assess
the probabilities of the outcomes to understand
the risk profile of the system.
• Recommend Preventive Measures: Based on
the analysis, suggest actions to mitigate the
identified risks.
ETA is a powerful tool that can be applied to a
wide range of systems, including nuclear power
plants, spacecraft, and chemical plants. It helps in
preventing negative outcomes by providing risk
assessors with the probability of occurrence for

13. Qualitative and Quantitative Risk Assessment
Qualitative and Quantitative Risk Assessments
are two fundamental approaches to risk analysis,
each with its own methodology and focus areas:
• Qualitative Risk Assessment:
• Subjective Analysis: It’s based on expert
judgment and experience rather than hard
numbers.
• Risk Rating: Risks are often rated on a scale
(e.g., low, medium, high) to prioritize them.
• Scenarios: It involves scenario-based analysis
to understand the impact of risks.
• First Line of Defense: It helps identify the most
significant risks that need immediate attention

14. • Quantitative Risk Assessment:
• Numerical Values: This approach assigns objective
numerical values to risks.
• Probability and Impact: It quantifies the likelihood of
risks occurring and their potential impact in
measurable terms.
• Data-Driven: Relies on historical data and
statistical methods for analysis.
• Detailed Analysis: It’s used for a more detailed
understanding of risks and is often applied after
qualitative analysis
The key difference between the two is that qualitative
analysis is based on subjective judgment, while
quantitative analysis relies on objective, specific data.
Qualitative analysis is useful for a broad initial

15. Checklist Analysis
Checklist Analysis is a method used to systematically review
materials or processes using a list to determine their accuracy
and completeness. It’s particularly useful in project
management and risk identification processes.
• Develop the Checklist: Based on knowledge from previous
projects and historical information, create a list of items,
steps, or tasks.
• Review the Checklist: Systematically go through the list to
check for accuracy and completeness of the project or
process.
• Identify Risks: Use the checklist to pinpoint potential risks
involved in the project management plan.
• Mitigate Risks: For any risks identified, come up with
appropriate mitigating measures.
• Evaluate and Update: After completing the analysis,
evaluate the recommendations and update the checklist to

16. Root cause analysis
Root Cause Analysis (RCA) is a methodical
approach used to identify the underlying reasons
for faults, problems, or incidents. It’s a critical
component of problem-solving that goes beyond
treating symptoms to understand and address the
fundamental causes. Here’s a general outline of
the RCA process:
• Identify the Problem: Clearly define the issue
that needs to be resolved.
• Gather Data: Collect information and evidence
related to the problem.
• Analyze the Data: Look for patterns and
relationships to determine potential causes.
• Identify Root Causes: Use tools like the “Five
Whys” or cause-and-effect diagrams to drill
down to the root causes.

17. • Develop Action Plan: Create a strategy to address the
root causes and prevent recurrence.
• Implement Solutions: Put the action plan into practice.
• Monitor and Adjust: Review the effectiveness of the
solutions and make adjustments as necessary.
RCA is widely used across various industries, including
manufacturing, healthcare, IT, and telecommunications. It
can be performed using different techniques such as
the Five Whys, Failure Mode and Effects Analysis
(FMEA), Fault Tree Analysis, Ishikawa diagrams,
and Pareto analysis.
The goal of RCA is not only to solve the problem but also
to provide context and information that will result in an
action or a decision. It emphasizes focusing on how and
why something happened, rather than who is

18. What-If Analysis
What-If Analysis is a decision-making tool used to
evaluate the potential outcomes of different scenarios by
changing various input values in a model. It’s commonly
used in financial modeling, project management, and
strategic planning. The process involves:
• Defining Scenarios: Establishing different scenarios
to explore how varying conditions might affect
outcomes.
• Changing Variables: Modifying one or more input
variables to see how changes influence the results.
• Analyzing Outcomes: Examining the effects of the
changes on the end results.
• Making Decisions: Using the insights gained from the
analysis to make informed decisions.

19. Hazard Identification and Risk Assessment
Hazard Identification and Risk Assessment (HIRA)
are critical processes used to maintain a high level of
safety and efficiency in the workplace. They involve
identifying potential risks and hazards, assessing
their severity, and implementing controls to mitigate
or eliminate those risks.
• Hazard Identification: Inspect the workspace and
processes to identify potential risks to human
health and safety. This step may involve regular
inspections, engaging employees, and analyzing
each job task for potential hazards.
• Risk Assessment: After identifying hazards,
assess their severity, likelihood, and other factors
to create a comprehensive plan for worker

20. The importance of HIRA cannot be overstated,
as it serves as the foundation for implementing
safety controls, policies, and best practices to
protect workers throughout operations. Safety
issues can cause significant harm not only to
individuals but also to the organization, making it
essential to conduct thorough hazard
identification and risk assessments.
Organizations may use various methods for
these processes, including inspections, hazard
analysis, and involving employees who work
closely with potential hazards. The goal is to
ensure that all potential threats to worker safety
are detected and addressed