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🛡️ Introduction to Process Safety Assessment Series v1.0

📖 Reading Time: 100-120 minutes 📊 Level: Intermediate 💻 Code Examples: 30

Introduction to Process Safety Assessment Series v1.0

From Safety Fundamentals to HAZOP, FMEA, and Anomaly Detection - Complete Practical Guide to Chemical Process Safety

Series Overview

This series is a four-chapter educational content that provides step-by-step learning from the fundamentals to practice of safety assessment in chemical processes. You will systematically master safety assessment methods required in industry, from basic concepts of process safety to HAZOP, FMEA, risk assessment, and anomaly detection.

Features:
- ✅ Practice-oriented: 30 executable Python code examples
- ✅ Systematic Structure: Four-chapter structure for progressive learning from basic theory to industrial applications
- ✅ Industrial Applications: Complete implementation of HAZOP, LOPA, SIL calculations, and F-N curves
- ✅ Latest Technologies: Machine learning-based anomaly detection, risk prediction, and safety analysis automation

Total Learning Time: 100-120 minutes (including code execution and exercises)


How to Learn

Recommended Learning Sequence

flowchart TD A[Chapter 1: Process Safety Fundamentals] --> B[Chapter 2: HAZOP and Risk Assessment] B --> C[Chapter 3: FMEA and Reliability Analysis] C --> D[Chapter 4: Anomaly Detection and Proactive Safety] style A fill:#e8f5e9 style B fill:#c8e6c9 style C fill:#a5d6a7 style D fill:#81c784

For Beginners (First-time learners of process safety):
- Chapter 1 → Chapter 2 → Chapter 3 → Chapter 4
- Time Required: 100-120 minutes

Chemical Engineering Practitioners (with basic knowledge of process design):
- Chapter 1 (brief review) → Chapter 2 → Chapter 3 → Chapter 4
- Time Required: 80-100 minutes

Safety Management Practitioners (with HAZOP or FMEA experience):
- Chapter 3 → Chapter 4
- Time Required: 50-60 minutes


Chapter Details

Chapter 1: Process Safety Fundamentals

📖 Reading Time: 25-30 minutes 💻 Code Examples: 8 📊 Difficulty: Intermediate

Learning Content

  1. Overview of Process Safety
    • What is Process Safety (difference from occupational safety)
    • History of Major Accidents (Bhopal, Flixborough, Texas City)
    • Hierarchy of Safety Management (PSM: Process Safety Management)
    • Concept of Risk (Hazard vs Risk)
  2. Hazard Identification Framework
    • Hazard Classification (Physical, Chemical, Biological)
    • Hazard Identification Methods (Checklist, What-if, HAZID)
    • Overview of Process Hazard Analysis (PHA)
    • Implementation of Hazard Identification System in Python
  3. Risk Assessment Fundamentals
    • Risk Matrix (Frequency × Consequence)
    • Risk Ranking and Prioritization
    • Tolerable Risk Criteria (ALARP: As Low As Reasonably Practicable)
    • Building a Risk Register
  4. Layer of Protection Analysis (LOPA)
    • LOPA Concepts and Procedures
    • Types of Protection Layers (IPL: Independent Protection Layer)
    • Risk Reduction Factor
    • Safety Integrity Level (SIL) Calculation

Learning Objectives

Read Chapter 1 →

Chapter 2: HAZOP and Risk Assessment

📖 Reading Time: 30-35 minutes 💻 Code Examples: 8 📊 Difficulty: Intermediate

Learning Content

  1. HAZOP Study Fundamentals
    • What is HAZOP (Hazard and Operability Study)
    • Application of Guide Words (No, More, Less, Reverse, etc.)
    • Deviation Analysis
    • Cause-Consequence-Safeguard
  2. HAZOP Automation System
    • P&ID (Piping and Instrumentation Diagram) Analysis
    • Automation of Guide Word Application
    • Comprehensive Generation of Deviation Scenarios
    • Automatic Generation of HAZOP Reports
  3. Quantitative Risk Assessment (QRA)
    • Event Frequency Analysis (Event Tree Analysis)
    • Failure Frequency Database (Generic Failure Rate)
    • Consequence Calculation (Consequence Modeling)
    • Individual Risk vs Societal Risk
  4. F-N Curves and Risk Criteria
    • Creating F-N Curves (Frequency-Consequence Curves)
    • Tolerability Criteria Lines
    • ALARP Demonstration
    • Risk Ranking and Prioritization

Learning Objectives

Read Chapter 2 →

Chapter 3: FMEA and Reliability Analysis

📖 Reading Time: 25-30 minutes 💻 Code Examples: 7 📊 Difficulty: Intermediate

Learning Content

  1. FMEA (Failure Mode and Effects Analysis)
    • FMEA Concepts and Procedures
    • Identification of Failure Modes
    • Calculation of RPN (Risk Priority Number)
    • Criticality Analysis
  2. Reliability Engineering Fundamentals
    • Reliability Function and MTBF (Mean Time Between Failures)
    • Life Prediction Using Weibull Distribution
    • Bathtub Curve and Failure Rate
    • Redundancy Design (Parallel and Series Systems)
  3. Fault Tree Analysis (FTA)
    • Definition of Top Event
    • Construction of Logic Gates (AND, OR)
    • Minimal Cut Sets
    • Calculation of System Reliability
  4. Preventive Maintenance Optimization
    • RCM (Reliability Centered Maintenance)
    • Failure Prediction Models
    • Optimization of Maintenance Intervals
    • Risk-Based Inspection (RBI)

Learning Objectives

Read Chapter 3 →

Chapter 4: Anomaly Detection and Proactive Safety

📖 Reading Time: 30-35 minutes 💻 Code Examples: 7 📊 Difficulty: Intermediate to Advanced

Learning Content

  1. Anomaly Detection Using Machine Learning
    • Unsupervised Learning (Isolation Forest, One-Class SVM)
    • Statistical Process Control (SPC)
    • Time Series Anomaly Detection (LSTM, Autoencoder)
    • Process Data Preprocessing
  2. Early Warning System
    • Anomaly Scoring
    • Threshold Setting and Optimization
    • Balance of False Positives/Negatives
    • Real-time Monitoring
  3. Root Cause Analysis (RCA)
    • Automation of 5 Whys Analysis
    • Causal Relationship Analysis
    • Correlation Analysis and Feature Importance
    • Accident Investigation Support Tools
  4. Proactive Safety Culture
    • Leading Indicators
    • Safety KPIs (Key Performance Indicators)
    • Safety Performance Dashboard
    • Continuous Improvement Cycle (PDCA)

Learning Objectives

Read Chapter 4 →


Overall Learning Outcomes

Upon completing this series, you will acquire the following skills and knowledge:

Knowledge Level (Understanding)

Practical Skills (Doing)

Application Ability (Applying)


FAQ (Frequently Asked Questions)

Q1: What level of prior knowledge in chemical engineering is required?

A: It is desirable to understand the fundamentals of chemical engineering (material balance, reaction engineering, unit operations) and basic risk management concepts. This assumes that you have completed chemical engineering courses at the university sophomore-junior level.

Q2: Is practical experience with HAZOP or FMEA required?

A: No, it is not required. This series allows you to learn from the fundamentals to practice of HAZOP and FMEA step by step. However, expert guidance is recommended for practical application.

Q3: What Python libraries are required?

A: Primarily uses NumPy, Pandas, Scikit-learn, Matplotlib, and Seaborn. TensorFlow/Keras is also used for anomaly detection. All can be installed via pip.

Q4: What is the relationship with the Process Simulation Series?

A: By applying the safety assessment methods of this series to models built in the Process Simulation Series, safety verification at the design stage becomes possible. Combining both series enables safe and efficient process design.

Q5: Can it be applied to actual chemical plants?

A: Yes. The methods in this series are widely used in industry. However, implementation requires safety regulations, internal standards, and expert review. Particularly for safety instrumented system (SIS) design, compliance with standards such as IEC 61511 is required.


Next Steps

Recommended Actions After Series Completion

Immediate (within 1 week):
1. ✅ Publish the anomaly detection system from Chapter 4 on GitHub
2. ✅ Assess safety evaluation opportunities for your company's processes
3. ✅ Try creating a simple risk matrix

Short-term (1-3 months):
1. ✅ Conduct HAZOP study on actual processes
2. ✅ Build machine learning-based anomaly detection system
3. ✅ Create safety KPI dashboard
4. ✅ Learn IEC 61511 (SIS standard)

Long-term (6 months or more):
1. ✅ Build Process Safety Management (PSM) system
2. ✅ Implement real-time anomaly detection system
3. ✅ Conference presentations or paper writing
4. ✅ Career development as a process safety engineer


Feedback and Support

About This Series

This series was created under Dr. Yusuke Hashimoto of Tohoku University as part of the PI Knowledge Hub project.

Creation Date: October 26, 2025
Version: 1.0

We Welcome Your Feedback

To improve this series, we look forward to your feedback:

Contact: yusuke.hashimoto.b8@tohoku.ac.jp


License and Terms of Use

This series is published under the CC BY 4.0 (Creative Commons Attribution 4.0 International) license.

You may:
- ✅ Freely view and download
- ✅ Use for educational purposes (classes, study sessions, etc.)
- ✅ Modify and create derivatives (translation, summarization, etc.)

Conditions:
- 📌 Author credit must be displayed
- 📌 Modifications must be indicated
- 📌 For commercial use, please contact in advance

Details: CC BY 4.0 License Full Text


Let's Get Started!

Are you ready? Start with Chapter 1 and begin your journey into the world of process safety assessment!

Chapter 1: Process Safety Fundamentals →


Update History


Your journey to learning process safety begins here!

References

  1. Montgomery, D. C. (2019). Design and Analysis of Experiments (9th ed.). Wiley.
  2. Box, G. E. P., Hunter, J. S., & Hunter, W. G. (2005). Statistics for Experimenters: Design, Innovation, and Discovery (2nd ed.). Wiley.
  3. Seborg, D. E., Edgar, T. F., Mellichamp, D. A., & Doyle III, F. J. (2016). Process Dynamics and Control (4th ed.). Wiley.
  4. McKay, M. D., Beckman, R. J., & Conover, W. J. (2000). "A Comparison of Three Methods for Selecting Values of Input Variables in the Analysis of Output from a Computer Code." Technometrics, 42(1), 55-61.

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