Contents
Preface...................................................................................................................
... [Show More] xvii
Introduction........................................................................................................xxiii
Part I Introductory Comments
1 About the Book................................................................................................3
1.1 Introduction............................................................................................3
1.2 Why Use Risk-Based Decision Making?.............................................4
1.3 Book Contents.........................................................................................6
1.4 Definitions...............................................................................................7
1.5 Risk Terms............................................................................................. 13
1.6 Financial Risk....................................................................................... 16
References........................................................................................................22
2 History of Environmental Health Problems............................................23
2.1 Introduction..........................................................................................23
2.2 First Humans........................................................................................25
2.3 Development of Agriculture..............................................................26
2.4 Colonization of the New World.........................................................28
2.5 Industrial Revolution...........................................................................29
References........................................................................................................33
3 History of Environmental Hazard Problems...........................................35
3.1 Introduction..........................................................................................35
3.2 Early Accidents.....................................................................................36
3.2.1 Great Chicago Fire..................................................................36
3.2.2 South Fork Dam: Johnstown, Pennsylvania....................... 37
3.2.3 Oppau, Germany.................................................................... 37
3.2.4 East Ohio Gas Company: Cleveland, Ohio.........................38
3.2.5 Texas City, Texas.....................................................................39
3.3 Recent Major Accidents.......................................................................40
3.3.1 Flixborough, England............................................................40
3.3.2 Seveso, Italy............................................................................. 41
3.3.3 Three Mile Island, Pennsylvania..........................................42
3.3.4 Chernobyl, Russia...................................................................43
3.3.5 Bhopal, India............................................................................45
3.3.6 Ashland Oil, Pennsylvania....................................................47
3.3.7 Trans World Airlines: Long Island, New York...................48
x Contents
3.4 Major Accidents in the Twenty-First Century.................................53
3.4.1 Y2K............................................................................................54
3.4.2 The Indian Ocean Earthquake and Tsunami.....................54
3.4.3 Katrina......................................................................................54
3.4.4 2010 Earthquakes....................................................................55
3.4.5 Chilean Mine Accident..........................................................56
3.4.6 BP Disaster...............................................................................56
3.5 Advances in Safety Features..............................................................60
References........................................................................................................63
4 Health Risk versus Hazard Risk................................................................65
4.1 Introduction..........................................................................................65
4.2 Introduction to the Health Risk Assessment Process..................... 67
4.3 Introduction to the Hazard Risk Assessment Process...................68
4.4 Qualitative Risk Scenarios.................................................................. 70
4.5 What Are the Differences?..................................................................72
4.6 Uncertainty Factors..............................................................................73
4.7 Future Trends in Environmental Risk Assessment........................ 74
References........................................................................................................75
5 Environmental Regulatory Framework....................................................77
5.1 Introduction..........................................................................................77
5.2 Regulatory System...............................................................................78
5.3 Laws and Regulations: The Differences........................................... 81
5.4 Role of the States..................................................................................83
5.5 Resource Conservation and Recovery Act.......................................83
5.6 Major Toxic Chemical Laws Administered by the U.S. EPA.........85
5.7 Legislative Tools for Controlling Water Pollution...........................89
5.7.1 Clean Water Act......................................................................89
5.7.2 Safe Drinking Water Act........................................................92
5.7.3 Marine Protection, Research, and Sanctuaries
Act (Title 1)...............................................................................94
5.8 Oil Pollution Act...................................................................................94
5.9 Superfund Amendments and Reauthorization Act (SARA)
of 1986....................................................................................................95
5.10 Clean Air Act........................................................................................99
5.10.1 Provisions for Attainment and Maintenance of
National Ambient Air Quality Standards......................... 100
5.10.2 Provisions Relating to Mobile Sources.............................. 101
5.10.3 Air Toxics............................................................................... 101
5.10.4 Acid Deposition Control...................................................... 102
5.10.5 Operating Permits................................................................. 103
5.10.6 Stratospheric Ozone Protection.......................................... 103
Contents xi
5.10.7 Provisions Relating to Enforcement................................... 103
5.10.8 Provisions Relating to Chemical Accidents
and Hazards.......................................................................... 105
5.11 Occupational Safety and Health Act............................................... 106
5.12 EPA’s Risk Management Program................................................... 108
5.13 Pollution Prevention Act of 1990...................................................... 113
References...................................................................................................... 114
6 Emergency Planning and Response........................................................ 117
6.1 Introduction........................................................................................ 117
6.2 Need for Emergency Response Planning....................................... 118
6.3 Planning Committee......................................................................... 119
6.4 Hazards Survey..................................................................................123
6.5 Plan for Emergencies......................................................................... 126
6.6 Training of Personnel........................................................................ 130
6.7 Notification of Public and Regulatory Officials............................ 131
6.8 Plan Implementation......................................................................... 133
6.8.1 General Questions................................................................ 134
6.8.2 Emergency Organization..................................................... 134
6.8.3 Emergency Action................................................................. 135
6.8.4 Alarms.................................................................................... 135
6.8.5 Communications................................................................... 135
6.8.6 Evacuation.............................................................................. 135
6.8.7 Accounting for Personnel.................................................... 135
6.8.8 First Aid.................................................................................. 136
6.8.9 Transportation....................................................................... 136
6.8.10 Security................................................................................... 136
6.8.11 Firefighting............................................................................ 136
6.8.12 Outside Agencies.................................................................. 136
6.8.13 Training.................................................................................. 136
6.9 Other State Regulatory Initiatives................................................... 137
6.9.1 New Jersey Toxic Catastrophe Prevention Act................. 138
6.10 Illustrative Examples......................................................................... 140
References...................................................................................................... 148
Part II Health Risk Assessment
7 Introduction to Health Risk Assessment................................................ 153
7.1 Introduction........................................................................................ 153
7.2 Health Risk Evaluation Process....................................................... 155
7.3 Health Problem Identification.......................................................... 157
7.4 Toxicology and Dose–Response....................................................... 158
xii Contents
7.5 Exposure Assessment........................................................................ 160
7.6 Health Risk Characterization........................................................... 161
References...................................................................................................... 164
8 Health Problem Identification.................................................................. 165
8.1 Introduction........................................................................................ 165
8.2 Toxicology Principles......................................................................... 168
8.3 Epidemiology Principles................................................................... 169
8.4 Molecular/Atomic Structural Analysis........................................... 171
8.5 Material Safety Data Sheets.............................................................. 172
8.6 Engineering Problem Solving.......................................................... 184
8.7 Fate of Chemicals in the Environment Related to
Health Problems................................................................................. 185
8.8 Carcinogens versus Noncarcinogens.............................................. 188
8.8.1 Noncarcinogens.................................................................... 188
8.8.2 Carcinogens........................................................................... 189
References...................................................................................................... 189
9 Toxicity and Dose–Response.................................................................... 191
9.1 Introduction........................................................................................ 191
9.2 Definitions........................................................................................... 192
9.3 Toxicology...........................................................................................200
9.4 Epidemiology......................................................................................203
9.5 Noncarcinogens.................................................................................. 207
9.5.1 Concept of Threshold...........................................................208
9.5.2 Derivation of an Oral RfD...................................................209
9.5.3 Derivation of an Inhalation RfD......................................... 210
9.5.4 Derivation of a Subchronic RfD.......................................... 211
9.5.5 Derivation of Developmental Toxicant RfD...................... 212
9.5.6 Calculation Scheme for Noncarcinogens.......................... 213
9.5.7 Dose–Response Relationships............................................ 213
9.6 Carcinogens........................................................................................ 214
9.6.1 Concept of Nonthreshold Effects........................................ 215
9.6.2 Assigning a Weight of Evidence......................................... 215
9.6.3 Generating a Slope Factor.................................................... 216
9.6.4 Identifying the Appropriate Data Set................................ 216
9.6.5 Dose–Response Relationships............................................ 219
9.7 Uncertainties/Limitations................................................................222
9.7.1 Uncertainties Related to Toxicity Information................. 224
References......................................................................................................233
10 Exposure Assessment.................................................................................235
10.1 Introduction........................................................................................235
10.2 Components of an Exposure Assessment...................................... 239
10.2.1 Step 1: Characterization of Exposure Setting................... 239
Contents xiii
10.2.2 Step 2: Identification of Exposure Pathways..................... 239
10.2.3 Step 3: Quantification of Exposure..................................... 240
10.2.4 Step 4: Quantification of Intakes......................................... 241
10.3 Dispersion in Water Systems............................................................ 242
10.3.1 Rivers and Estuaries.............................................................244
10.3.2 Lakes and Impoundments................................................... 246
10.3.3 Groundwater......................................................................... 247
10.4 Dispersion in Soils.............................................................................250
10.5 Dispersion in the Atmosphere.........................................................253
10.5.1 Effective Height of Atmospheric Emissions.....................253
10.5.2 Atmospheric Dispersion Equations for
Continuous Sources..............................................................258
10.5.3 Atmospheric Dispersion Equations for
Instantaneous Sources......................................................... 276
References...................................................................................................... 282
11 Health Risk Characterization...................................................................283
11.1 Introduction........................................................................................283
11.2 Qualitative Health Risk Scenarios...................................................285
11.3 Quantitative Risk: Noncarcinogens................................................289
11.3.1 Risks for Multiple Substances.............................................290
11.3.2 Noncarcinogenic Effects: Chronic Exposures..................290
11.3.3 Noncarcinogenic Effects: Subchronic Exposures............. 291
11.3.4 Noncarcinogenic Effects: Less than
2 Week Exposures................................................................ 291
11.3.5 Segregation of Hazard Indices............................................ 292
11.3.6 Combining Risks across Exposure Pathways................... 292
11.4 Quantitative Risk: Carcinogens....................................................... 295
11.4.1 Risks for Multiple Substances............................................. 296
11.4.2 Combining Risk across Exposure Pathways..................... 297
11.5 Risk Uncertainties/Limitations....................................................... 301
11.5.1 Uncertainty and Variability................................................302
11.5.2 Assessment and Presentation of Uncertainty...................304
11.6 Risk-Based Decision Making............................................................305
11.7 Public Perception of Risk..................................................................306
11.7.1 Everyday Risks......................................................................307
11.7.2 Outrage Factors.....................................................................307
References...................................................................................................... 317
Part III Hazard Risk Assessment
12 Introduction to Hazard Risk Assessment.............................................. 321
12.1 Introduction........................................................................................ 321
12.2 Risk Evaluation Process for Accidents............................................ 323
xiv Contents
12.3 Hazard Identification........................................................................ 326
12.4 Probability and Causes of Accidents............................................... 329
12.5 Consequences of Accidents.............................................................. 331
12.6 Hazard Risk Characterization......................................................... 331
References......................................................................................................334
13 Hazard/Event Problem Identification......................................................335
13.1 Introduction........................................................................................335
13.2 Process Equipment.............................................................................336
13.2.1 Reactors..................................................................................336
13.2.2 Heat Exchangers...................................................................336
13.2.3 Mass Transfer Equipment.................................................... 337
13.2.3.1 Distillation Columns............................................ 337
13.2.3.2 Adsorbers............................................................... 337
13.2.3.3 Absorbers................................................................338
13.2.4 Ancillary Equipment............................................................339
13.2.5 Environmental Control Equipment...................................340
13.2.6 Utilities................................................................................... 341
13.2.7 Protective and Safety Systems............................................342
13.2.8 Process Diagrams.................................................................343
13.2.9 Plant Siting and Layout........................................................344
13.3 Classification of Accidents................................................................347
13.3.1 Equipment Failures..............................................................348
13.3.2 Human Errors and Occupational Mishaps.......................350
13.3.2.1 Human Element.....................................................350
13.3.2.2 Task Variables........................................................ 351
13.3.2.3 Environmental Element....................................... 351
13.3.3 Transport Accidents............................................................. 352
13.3.4 Electrical Failures..................................................................353
13.3.5 Nuclear Accidents.................................................................354
13.3.6 Natural Disasters..................................................................356
13.4 Fires, Explosions, Toxic Emissions, and Hazardous Spills.......... 359
13.4.1 Fire Fundamentals................................................................359
13.4.2 Plant Fires..............................................................................363
13.4.3 Causes of Plant Fires............................................................365
13.4.4 Explosion Fundamentals.....................................................366
13.4.5 Unconfined Vapor Cloud Explosions (UVCEs)................ 370
13.4.6 Plant Explosions.................................................................... 370
13.4.7 Toxic Emissions..................................................................... 373
13.4.8 Hazardous Spills................................................................... 374
13.5 Hazard Event Evaluation Techniques.............................................377
13.5.1 System Checklists.................................................................380
13.5.2 Safety Reviews/Safety Audits............................................ 381
13.5.3 “What If” Analyses............................................................... 382
Contents xv
13.5.4 Preliminary Hazard Analyses (PHAs)..............................383
13.5.5 Hazard and Operability (HAZOP) Studies......................384
References...................................................................................................... 392
14 Hazard/Event Probability.......................................................................... 395
14.1 Introduction........................................................................................ 395
14.2 Accident Causes................................................................................. 395
14.3 Series and Parallel Systems.............................................................. 398
14.4 Probability Distributions..................................................................403
14.4.1 Binomial Distribution..........................................................406
14.4.2 Poisson Distribution.............................................................408
14.4.3 Exponential Distribution..................................................... 410
14.4.4 Normal Distribution............................................................. 412
14.4.5 Log-Normal Distribution..................................................... 416
14.5 Weibull Distribution.......................................................................... 424
14.6 Fault Tree Analysis............................................................................430
References......................................................................................................438
15 Hazard/Event Consequences.....................................................................439
15.1 Introduction........................................................................................439
15.2 Accident Minimization/Prevention................................................440
15.3 Consequence Estimation................................................................... 452
15.4 Failure Modes, Effects, and Criticality Analysis (FMECA).........458
15.5 Vulnerability Analysis...................................................................... 461
15.6 Event Tree Analysis...........................................................................468
References...................................................................................................... 475
16 Hazard Risk Characterization..................................................................477
16.1 Introduction........................................................................................477
16.2 Risk Characterization........................................................................480
16.3 Public Perception of Risk..................................................................482
16.4 Risk Communication.........................................................................482
16.5 Cause–Consequence Analysis.........................................................487
16.6 Qualitative Hazard Risk Assessment.............................................489
16.7 Uncertainties/Limitations................................................................ 494
16.8 Quantitative Hazard Risk Assessment........................................... 497
References......................................................................................................507
Part IV Case Studies
17 The Case for Case Studies......................................................................... 511
17.1 Introduction........................................................................................ 511
17.2 Case Study Criteria: Is It Logical, Relevant, and Reasonable?...... 512
xvi Contents
17.3 Preparing a Case Study Solution..................................................... 512
Reference........................................................................................................ 513
18 Monte Carlo Simulation............................................................................. 515
18.1 Introduction........................................................................................ 515
18.2 Case Study 1: Time to Pump Failure............................................... 516
18.3 Case Study 2: Time to Failure of Two Electrical Components....... 518
18.4 Case Study 3: Nuclear Plant Temperature Gauge Lifetime......... 521
18.5 Case Study 4: Bus Section Failures in Electrostatic
Precipitators........................................................................................ 525
References...................................................................................................... 528
19 Emergency Planning and Response........................................................ 529
19.1 Introduction........................................................................................ 529
19.2 Case Study 1: Terrorist Attack of a Pharmaceutical
Company’s Plant in Greenpoint, Brooklyn, New York................. 529
19.3 Case Study 2: Terrorist Attack of the Brooklyn
Navy Yard in Greenpoint, Brooklyn, New York............................ 531
19.4 Case Study 3: Plans to Counter the Possibility of a Process
or Plant-Related Accident at the “Wedo” Chemical Facility
in Suffolk County, Long Island, New York....................................533
19.5 Case Study 4: Dilution Ventilation Models....................................538
References......................................................................................................548
20 Natural Disasters.........................................................................................549
20.1 Introduction........................................................................................549
20.2 Case Study 1: Hurricanes..................................................................550
20.3 Case Study 2: Floods.......................................................................... 559
20.4 Case Study 3: Earthquakes............................................................... 562
20.5 Case Study 4: Meteorites...................................................................566
20.6 Case Study 5: Combined Hurricanes and Flooding..................... 569
References...................................................................................................... 571
21 Industrial Accidents.................................................................................... 573
21.1 Introduction........................................................................................ 573
21.2 Case Study 1: Nanochemical Plant Accident................................. 573
21.3 Case Study 2: Caustic Tank Preliminary Hazard Analysis......... 579
21.4 Case Study 3: Transportation of Hazardous Chemicals..............583
21.5 Case Study 4: Offshore Rig Accident..............................................586
References...................................................................................................... 589
Afterword............................................................................................................. 591
xvii
Preface
And I honor the man who is willing to sink
Half his present repute for the freedom to think,
And, when he has thought, be his cause strong or weak,
Will risk t’ other half for the freedom to speak.
James R. Russell (1819–1891)
A Fable for Critics
Risk. Health risk. Hazard risk. Individual risk. Societal risk. Etc. Risk has
surged to the forefront of numerous engineering and scientific areas of
interest. Why? A good question. Some of the more obvious reasons include
(not in the order of importance) the following:
1. Increased environmental health and safety legislation
2. The accompanying massive regulations
3. Regulatory fines
4. Liability concerns
5. Environmental activists and their organizations
6. Public concerns
7. Skyrocketing health-care costs
8. Skyrocketing workers’ compensation costs
9. Codes of ethics
These factors, individually or in toto, have created a need for engineers and
scientists to develop a proficiency in risk and risk-related areas. In turn, this
need has given rise to the driving force that led to the writing of this book.
Specific details follow.
Society has indeed experienced the aforementioned dramatic explosion
(no pun intended) in technological advances that continue to accelerate.
These advances include new domestic products, new drugs, sophisticated
industrial processes, energy exploration and development, and expansion
into outer space, all of which have introduced (particularly in the workplace)
new diseases, have complicated numerous earlier health-related problems,
and have caused unanticipated accidents.
The rapid growth and expansion of the chemical and petroleum industry have been accompanied by a simultaneous rise in both human health
problems and human, material, and property losses because of fires, explosions, hazardous and toxic spills, equipment failures, other accidents, and
xviii Preface
business interruptions. Concern over the potential consequences of massive
emissions of “harmful” chemicals and catastrophic accidents, particularly at
chemical and petrochemical plants, has sparked interest at both the industrial and regulatory levels in obtaining a better understanding of the subject
of this book, Environmental Health and Hazard Risk Assessment: Principles and
Calculations. The writing of this book was also undertaken, in part, as a result
of this growing concern.
In the wake of the British Petroleum (BP) Deepwater Horizon offshore oil
rig explosion on April 20, 2010, and the accompanying millions of gallons
of oil that were released into the Gulf of Mexico from the damaged rig, the
general subject of environmental risk suddenly took on a never-dreamed-of
level of importance at the national level. How and why this disaster occurred
is still being debated by engineers, scientists, politicians, regulators, and the
average citizen. One thing that cannot be debated is that the BP rig catastrophe produced the worst environmental disaster in American history.
Officials of not only BP but also Exxon Mobil, Conoco Philips, Shell, and
Chevron continue to insist that the accident was an aberration and could
not happen again. Really? The scientific community knows better since accidents are an integral part of life; discussions of this nature have to ultimately
lead to an often-misunderstood term referred to as “risk.”
The subject of emergency preparedness and response has also surfaced.
Immediately following the BP disaster, steps were taken not only to prepare
for the environmental effects associated with the massive emission that
occurred but also to institute programs and actions to help reduce (or possibly eliminate) the probability of this occurring again. For example, the oil
from the blown-out deepwater well had the potential to move up the Atlantic
coast and ultimately reach Long Island (home to one of the authors), beaches,
and local estuaries. Nassau County worked with New York City in tracking
the currents of the spill at the time. In addition to tracking that spill, the
County was in partnership with other municipalities in drafting an oil spill
response plan to address any local impacts.
In recent years, the engineering profession has expanded its responsibilities to society to include environmental risk, with particular emphasis on
accidents and massive emissions arising at industrial sources. Increasing
numbers of engineers, scientists, technicians, and maintenance personnel
are now confronting problems in this most important area. To cope with
these challenges, the engineers and scientists of today and tomorrow must
develop both a proficiency in environmental risk and an improved understanding of the subject. Because environmental risk is a highly sophisticated
and complex endeavor, many company administrators and regulatory officials are seeking highly trained and professionally educated personnel to
fill positions in this area. Thus, companies and government agencies have
acquired an interest in the continuing education of employees and students.
It was also in the spirit of responding to this particular concern that this
book was undertaken.
Preface xix
Regarding students, the Accreditation Board for Engineering and
Technology (ABET) requires that engineering graduates understand the
engineer’s responsibility to protect both the public and workers’ safety.
Traditionally, engineering schools have done an excellent job of educating
their students on the fundamental laws of nature governing their fields
and on the application of these laws to the solution of engineering problems. Unfortunately, they have been less successful in conveying to the students the importance of occupational health and environmental safety in the
design of chemical processes. This concern also served as a driving force for
the writing of this book.
This book is intended primarily for regulatory officials, company administrators, engineers, technicians, industry maintenance personnel, and
both undergraduate and first-year graduate students. It is assumed that the
reader has taken basic courses in physics and chemistry; only a minimum
background in mathematics is required (though calculus is desirable). Our
aims are to offer the reader the fundamentals of health risk and hazard
risk assessment with appropriate practical applications in the chemical
process industries, and to provide an introduction to the specialized and
reference books in this and related areas. The reader is encouraged to use
the works cited in the bibliography to continue development beyond the
scope of this book.
As is usually the case in preparing a manuscript, the decisions of what to
include and what to omit have been difficult. However, every attempt has
been made to offer engineering and science course material to readers at a
level that will enable them to better cope with some of the complex problems
encountered in this field.
This book is divided into four parts. Part I (Introductory Comments) serves
as an introduction to t [Show Less]