Guidelines for Determining the Probability of Ignition of a Released Flammable Mass

FORWARD XI
 
1 INTRODUCTION 1
 
1.1 Objectives 1
 
1.2 Motivation for this Book 1
 
1.2.1 A Brief History of Fire Protection 2
 
1.2.2 The Development of Risk-Based Approaches to Flammables Management 3
 
1.2.3 Difficulties in Developing Ignition Probability Prediction Methods 4
 
1.2.4 Missing Variables 5
 
1.2.5 Summary of Industry Needs and Path Forward 5
 
1.2.6 Applications for This Book 6
 
1.2.7 Limitations in Applying the Approaches in This Book 7
 
1.3 Ignition Probability Overview 8
 
1.3.1 Theoretical Basis for Ignition 8
 
1.3.2 Key Ignition Factors Related to the Properties of the Fuel, and Available Surrogates that can be Used for Developing Probability of Ignition Predictions 13
 
1.3.3 Key Ignition Factors Related to the Release Source 19
 
1.3.4 Key Ignition Factors Related to the External Environment After the Release 27
 
1.4 Control of Ignition Sources 30
 
1.4.1 Ignition Source Management 30
 
1.4.2 Minimization of Release 33
 
1.5 Vapor Cloud Explosion Probability Overview 33
 
1.6 Detonation Overview 35
 
1.6.1 Detonation Using a Strong Ignition Source 35
 
1.6.2 Deflagration-to-Detonation Transition 35
 
1.6.3 Buncefield 35
 
1.7 Other Ignition Topics - Hydrogen 36
 
1.7.1 Ignition Mechanisms 36
 
1.7.2 Other Hydrogen Ignition Topics 37
 
2 ESTIMATION METHODS 39
 
2.1 Introduction 39
 
2.1.1 Event Tree 39
 
2.1.2 Failure Frequency Data for Use in Event Trees 41
 
2.1.3 Quantification of the Event Tree 41
 
2.2 Factors Influencing the Probability of Immediate Ignition 41
 
2.2.1 Temperature of Release Relative to the Autoignition Temperature 42
 
2.2.2 Minimum Ignition Energy (MIE) of Material Being Released 42
 
2.2.3 Pyrophoricity of Released Material 44
 
2.2.4 Pressure/Velocity of Discharge