This edition first published 2018
© 2018 the American Institute of Chemical Engineers

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The American Institute of Chemical Engineers (1e, 2003)

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ISBN: 978-1-119-47463-0

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CONTENTS

ACRONYMS AND ABBREVIATIONS

GLOSSARY

ACKNOWLEDGMENTS

FOREWORD

PREFACE

1 INTRODUCTION

1.1 OBJECTIVES
1.2 A SITING AND LAYOUT APPROACH
1.3 HOW TO USE THIS GUIDELINE
1.4 THE PROTECTION LAYERS
1.5 TERMINOLOGY
1.6 GUIDELINE REFERENCES
1.7 SEPARATION DISTANCES BASED PRIMARILY ON FIRE CONSEQUENCES

2 OVERVIEW OF BENEFITS

2.1 IMPLICATIONS OF SITING AND LAYOUT
2.2 MANAGEMENT OF RISKS
2.3 IMPLEMENTING A STEP-WISE APPROACH FOR THE SITING AND LAYOUT OF FACILITIES
2.4 ANTICIPATING THE CHANGING WORLD
2.5 SUMMARIZING THE BUSINESS CASE FOR PROPER SITING OF A FACILITY

3 IDENTIFYING THE PROCESS HAZARDS AND RISKS

3.1 INTRODUCTION
3.2 DESCRIBING THE FACILITY’S SCOPE
3.3 SCREENING FOR PRELIMINARY HAZARDS
3.4 EVALUATING THE RISKS
3.5 CHECKLIST FOR IDENTIFYING THE PROCESS HAZARDS AND RISKS
3.6 SUMMARY

4 SELECTING A FACILITY LOCATION

4.1 INTRODUCTION
4.2 ADDITIONAL INFORMATION ON THE FACILITY
4.3 SELECTING A TEAM TO LOCATE THE FACILITY
4.4 GUIDELINES WHEN SURVEYING POTENTIAL FACILITY LOCATIONS
4.5 DETERMINING THE LOCATION PLOT SIZE
4.6 CONSTRUCTION AND TURNAROUND ISSUES
4.7 MAPS AND INFORMATION
4.8 GEOLOGICAL ISSUES
4.9 WEATHER ISSUES
4.10 SEISMIC ISSUES
4.11 OFF-SITE ISSUES
4.12 SECURITY ISSUES
4.13 ENVIRONMENTAL ISSUES
4.14 INFRASTRUCTURE ISSUES
4.15 BUILDING AND STRUCTURE ISSUES
4.16 MATERIAL HANDLING ISSUES
4.17 COMMUNICATIONS ISSUES
4.18 ENGINEERING DESIGN ISSUES
4.19 UTILITIES ISSUES
4.20 OTHER CHARACTERISTICS
4.21 PREPARING THE INFORMATION WHEN COMPARING LOCATIONS
4.22 A SITING AND LAYOUT ILLUSTRATION
4.23 CHECKLIST FOR SELECTING A FACILITY LOCATION
4.24 SUMMARY

5 SELECTING THE PROCESS UNIT LAYOUT WITHIN A FACILITY

5.1 INTRODUCTION
5.2 BLOCK LAYOUT METHODOLOGY OVERVIEW
5.3 HOW THE BLOCK LAYOUT INTEGRATES WITH THE FACILITY LOCATION
5.4 APPLYING PREVENTIVE MEASURES WHEN ARRANGING PROCESS UNITS
5.5 APPLYING MITIGATIVE MEASURES WHEN ARRANGING PROCESS UNITS
5.6 CONSTRUCTION AND TURNAROUNDS
5.7 THE BLOCK LAYOUT APPROACH: STEP 1 - EVALUATING THE LOCATION’S CHARACTERISTICS
5.8 OFF-SITE ISSUES
5.9 SECURITY ISSUES
5.10 ENVIRONMENTAL ISSUES
5.11 INFRASTRUCTURE ISSUES
5.12 THE BLOCK LAYOUT APPROACH: STEP 2 - EVALUATING THE SEPARATION DISTANCES BETWEEN BLOCKS
5.13 CRITICAL AND OCCUPIED STRUCTURES
5.14 MATERIAL HANDLING
5.15 PROCESS UNITS
5.16 TANK FARMS
5.17 OTHER AREAS
5.18 UTILITIES
5.19 OPTIMIZING THE LOCATIONS OF THE PROCESS UNITS
5.20 RESOLVING BLOCK LAYOUT OPTIMIZATION ISSUES
5.21 CONTINUING THE SITING AND LAYOUT ILLUSTRATION
5.22 CHECKLIST FOR SELECTING THE LAYOUT OF PROCESS UNITS WITHIN A FACILITY
5.23 SUMMARY

6 SELECTING THE EQUIPMENT LAYOUT WITHIN A PROCESS UNIT

6.1 INTRODUCTION
6.2 EQUIPMENT LAYOUT METHODOLOGY OVERVIEW
6.3 HOW THE EQUIPMENT LAYOUT INTEGRATES WITH THE BLOCK LAYOUT
6.4 APPLYING PREVENTIVE MEASURES WHEN ARRANGING EQUIPMENT
6.5 APPLYING MITIGATIVE MEASURES WHEN ARRANGING EQUIPMENT
6.6 CRITICAL AND OCCUPIED STRUCTURE DESIGN
6.7 EQUIPMENT
6.8 RESOLVING EQUIPMENT LAYOUT OPTIMIZATION ISSUES
6.9 CONTINUING THE SITING AND LAYOUT ILLUSTRATION
6.10 CHECKLIST FOR SELECTING THE EQUIPMENT LAYOUT WITHIN A PROCESS UNIT
6.11 SUMMARY

7 MANAGING CHANGES

7.1 INTRODUCTION
7.2 ADDRESSING SURROUNDING COMMUNITY AND INDUSTRIAL EXPANSIONS
7.3 A SITING AND LAYOUT APPROACH WHEN MANAGING CHANGES
7.4 MAINTAINING FACILITY INTEGRITY DURING ITS LIFE CYCLE
7.5 MANAGING EXPANSIONS AT AN EXISTING FACILITY
7.6 MANAGING PURCHASES OF EXISTING FACILITIES
7.7 MONITORING CHANGES WITH PERIODIC REVIEWS
7.8 ADDRESSING SITING AND LAYOUT ISSUES WHICH ARE IDENTIFIED DURING EXPANSIONS
7.9 SUMMARY

8 CASE HISTORIES

9 REFERENCES

10 APPENDICES

APPENDIX A. ADDITIONAL SITING AND LAYOUT REFERENCES

APPENDIX B. CCPS RECOMMENDED DISTANCE TABLES FOR SITING AND LAYOUT OF FACILITIES

APPENDIX C. CHECKLIST FOR IDENTIFYING THE PROCESS HAZARDS AND RISKS

APPENDIX D. CHECKLIST FOR SELECTING A FACILITY LOCATION

APPENDIX E. CHECKLIST FOR SELECTING THE PROCESS UNIT LAYOUT WITHIN A FACILITY

APPENDIX F. CHECKLIST FOR SELECTING THE EQUIPMENT LAYOUT WITHIN A PROCESS UNIT

INDEX

EULA

List of Tables

Chapter 1

Table 1.1
Table 1.2

Chapter 3

Table 3.1

Chapter 4

Table 4.1
Table 4.1

Chapter 5

Table 5.1
Table 5.2
Table 5.3
Table 5.4
Table 5.5
Table 5.6
Table 5.7
Table 5.8
Table 5.9
Table 5.10

Chapter 6

Table 6.1

Chapter 7

Table 7.1
Table 7.2

Chapter 8

Table 8.1

Appendices

Table 10.1

Appendix A

Table A.1
Table A.2
Table A.3
Table A.4
Table A.5
Table A.6
Table A.7
Table A.8

Appendix C

Table C.1

Appendix D

Table D.1

Appendix E

Table E.1

Appendix F

Table F.1

List of Illustrations

Chapter 1

Figure 1.1. A Siting and Layout Approach
Figure 1.2. A Facility’s Protection Layers
Figure 1.3. Guideline Terminology

Chapter 2

Figure 2.1. The Effect of Time on the Options for Reducing Process Safety Risks
Figure 2.2. Life cycle Phases for a Facility, a Process Unit, or the Equipment
Figure 2.3. The Chapters Corresponding to the Steps for Siting and Laying out of Facilities

Chapter 3

Figure 3.1. An illustration of potential flammability limit contours for flash fires
Figure 3.2. An illustration of potential thermal radiation contours from pool or jet fires
Figure 3.3. An illustration of potential blast overpressure contours
Figure 3.4. An illustration of potential toxic release endpoint contours from a small leak using the ERPG guidance
Figure 3.5. An illustration of potential toxic release endpoint contours from a small leak using probits

Chapter 4

Figure 4.1. Typical Land Use Guidance for the Land Surrounding a Facility
Figure 4.2. Characteristics Considered when Selecting a Facility Location
Figure 4.3. A Southeast “Prevailing Wind” Direction shown on a Wind Rose Diagram
Figure 4.4. Location 1-Proposed Inland Site in Remote Area
Figure 4.5. Location 2-Proposed Inland Site with Nearby Development

Chapter 5

Figure 5.1. Flowchart used to Determine the Process Unit Layout Distances at a Facility
Figure 5.2. An Example of a Modeled Dispersion Profile
Figure 5.3. How Layout Distances are Measured at a Facility
Figure 5.4. Blast Overpressure Contours for the Proposed Site
Figure 5.5. Block Layout Diagram for the New Low Hazard Operation
Figure 5.6. Block Layout Diagram with Layout Distances for the New Low Hazard Operation
Figure 5.7. Building Damage Levels as a Function of Pressure-Impulse Curves
Figure 5.8. Rail Car Fragment thrown from the Crescent City BLEVE
Figure 5.9. Location 3 Facility Layout for its Structures and Process Unit Blocks

Chapter 6

Figure 6.1. Flowchart used to Determine Equipment Layout Distances within a Process Unit
Figure 6.2. Computer Aided Design (CAD) Image Depicting a Proposed Layout of Equipment within a Process Unit
Figure 6.3. Traditional Pump Row / Pipeway Arrangement when Transferring Materials in Overhead Piping
Figure 6.4. A Safer Process Unit Pump Row / Pipeway Arrangement when Transferring Flammable Materials in Overhead Piping
Figure 6.5. An Example Hazardous Area / Zone Classification Drawing using a 3D Facility Plot Plan
Figure 6.6. The DuPont Brandywine Powder Mills
Figure 6.7. Layout of the Ethylene Unit’s Process Unit Blocks for Location 3
Figure 6.8. Layout of the Equipment in the Cracking Furnace Unit for Location 3

Chapter 7

Figure 7.1. A Siting and Layout Approach when Managing Changes
Figure 7.2. Managing Siting and Layout Changes within the Equipment, Process Unit, and Facility Life Cycles
Figure 7.3. The Separation Distances at the Existing Process Unit
Figure 7.4. The Proposed Layout for the Expansion Project at an Existing Facility

Chapter 8

Figure 8.1. Layout of the area surrounding the ISOM unit at Texas City
Figure 8.2. Image of PEPCON after Initial Explosion
Figure 8.3. Aerial View of the Explosion Damage in Danvers
Figure 8.4. Area Plot Plan and Impacted Areas Surrounding the PEMEX LPG Facility
Figure 8.5. Growth of the Community Surrounding the PEMEX LPG Facility
Figure 8.6. Images after the Explosion at the Little General Store
Figure 8.7. Flames Developing and Impinging on valero’s No. 1 Extractor Piping
Figure 8.8. The Pipe Bridge after the Incident at Valero
Figure 8.9. Range of Off-site Damage at Praxair in St. Louis
Figure 8.10. Range of the Vapor Cloud at Amuay
Figure 8.11. Range of the Blast Radius at West Fertilizer Company
Figure 8.12. Image of Damage from the West Fertilizer Company Explosion
Figure 8.13. Damage to the Concept Sciences Inc. Facility
Figure 8.14. T2 Laboratories, Inc., after the Explosion
Figure 8.15. Fragment of the T2 Laboratories 3-inch (7.6 cm) Thick Reactor
Figure 8.16. The Imperial Sugar Facility after the Explosions and Fires

Appendix D

Figure D.1. The Conservation Balance Across a Facility’’’s Property Line

Glossary

This Glossary contains the terms specific to this Guideline and process safety related terms from the CCPS Process Safety Glossary. The specific CCPS process safety related terms in this Guideline are current at the time of publication; please access the CCPS website for potential updates to the CCPS Glossary.

Term	Definition
Access Ways	Travel ways that provide occasional access to equipment or congested areas of a facility for maintenance, security, and firefighting vehicles. Also known as tertiary roadways.
Alternative Release Scenario (ARS)	The basis for an off-site consequence analysis required by the United States EPA Risk Management Program (RMP) Rule. This release scenario has less adverse consequences, but is more likely than the Worst Case Scenario. See Maximum Credible Event (MCE) and Worst Case Scenario (WCS).
As Low As Reasonably Practicable (ALARP)	The concept that efforts to reduce risk should be continued until the incremental sacrifice (cost, time, effort, or other expenditure of resources) is grossly disproportionate to the incremental risk reduction achieved. The term as low as reasonably achievable (ALARA) is often used synonymously.
Barrier	See Safeguard.
Boilover	A violent expulsion of contents caused by a heat wave from the surface burning at the top of the tank reaching the water layer at the bottom of the tank.
Brownfield	An industrial or commercial property that is abandoned or underused and is being considered as a location for a new facility or for redevelopment.
Buffer Zone	Additional undeveloped land surrounding the facility, often purchased to provide additional distance between the hazards and the surrounding community, which helps reduce the likelihood or severity of potential off-site impact, or helps reduce the likelihood of future community growth next to the facility.
Building	A rigid, enclosed structure.
Chambering	Enclosing a hazardous process unit within a building such that toxic materials are confined during a loss of containment (risk is unacceptable if the toxic material escapes).
Combustible Material	Materials that cause fires.
Combustible dust	A finely divided combustible particulate solid that presents a flash fire hazard or explosion hazard when suspended in air or the process-specific oxidizing medium over a range of concentrations [NFPA 652, NFPA 654].
Complex	A collection of facilities that may or may not be owned by the same company, but are located within the contiguous boundaries of a specific geographic location, such as an industrial or chemical park. A facility within a complex may feed or take raw materials from another facility in the complex or may be totally independent of its industrial neighbors.
Confinement	Obstacles such as walls and ceilings of a building, vessel, pipe, etc. that serve to limit the expansion of a dispersing burning vapor cloud.
Congestion	Obstacles in the path of the flame that generate turbulence and compression.
Containment	A system characteristic which prevents reactants or products from being exchanged between the chemical system and its environment.
Critical Equipment	Equipment, instrumentation, controls, or systems whose malfunction or failure would likely result in a catastrophic release of highly hazardous chemicals, or whose proper operation is required to mitigate the consequences of such release.
Critical Infrastructure	Systems and assets, whether physical or virtual, so vital that the loss, interruption, incapacity, or destruction of which (1) would have a negative or debilitating effect on the security, economic security, public health, or safety of a nation, region, or any local government, or (2) cause national or regional catastrophic effects.
Domino Effect	The triggering of secondary events, such as toxic releases, by a primary event, such as an explosion, such that the result is an increase in consequences or area of an effect zone. Generally only considered when a significant escalation of the original incident results.
Emergency Planning Response Guidelines (ERPG)	A system of guidelines for airborne concentrations of toxic materials prepared by the AIHA. For example, ERPG-2 is the maximum airborne concentration below which it is believed nearly all individuals could be exposed for up to one hour without experiencing or developing irreversible or other serious health effects or symptoms that could impair an individual’s ability to take protective action.
Equipment	A piece of hardware which can be defined in terms of mechanical, electrical or instrumentation components contained within its boundaries.
Facility	Sometimes also called a plant. The physical location where a management system activity is performed. In early life cycle stages, a facility may be the company’s central research laboratory, pilot plant, or the engineering offices of a technology vendor. In later stages, the facility may be a typical chemical plant, storage terminal, distribution center, or corporate office. In the context of this document, a facility is a portion of or a complete plant, unit, site, complex or offshore platform or any combination thereof.
Fixed facility	A portion of or a complete plant, unit, site, complex or any combination thereof that is generally not moveable. In contrast, mobile facilities, such as ships (e.g., transport vessels, floating platform storage and offloading vessels, drilling platforms), trucks, and trains, are designed to be movable.
Flammable Material	Materials that cause fires.
Grassroots	Totally new facility that may be built upon a greenfield or brownfield location.
Greenfield	Undeveloped property that has not been used before for either commercial or industrial purposes and is being considered as a location for a new facility.
Hazard	An inherent chemical or physical characteristic that has the potential for causing damage to people, property, or the environment. (Note: This guideline refers to “process safety” chemical hazards, such as their toxicity, flammability, and reactivity, and physical hazards, such as extreme processing conditions such as high pressures and temperatures.)
Hazardous Area Classification (HAC)	Locations which are classified depending on the properties of the flammable gas, flammable liquid-produced vapor, combustible liquid-produced vapors, combustible dusts, or fibers/flyings that may be present, and the likelihood that a flammable or combustible concentration or quantity is present [adapted from Article 500 of NFPA 70, National Electrical Code]. See Zone.
Hazardous Process Area or Unit	An area containing equipment (e.g., pipes, pumps, valves, vessels, reactors, and supporting structures) intended to process or store materials. Hazardous process areas/units have the potential for explosion, fire, or toxic material releases.
Hazard Zone	For an incident that produces an outcome such as toxic release, the hazard zone is the area over which the airborne concentration equals or exceeds some level of concern. For a flammable release, the area of effect is based on a specified level of thermal radiation. For a release that results in explosion, this is the area defined by specified overpressure levels.
Infrastructure	The basic facilities, services, and installations needed for the functioning of a site such as transportation and communications systems, water and power lines, and public institutions including emergency response organizations.
Inherently Safer	A condition in which the hazards associated with the materials and operations used in the process have been reduced or eliminated, and this reduction or elimination is permanent and inseparable from the process.
Knock-on Effect	See Domino Effect.
Layer of Protection	A concept whereby a device, system, orhuman action is provided to reduce the likelihood and/or severity of a specific loss event.
Layout	The relative location of equipment or buildings within a given site.
Life Cycle	The stages that a physical process or a management system goes through as it proceeds from birth to death. These stages include conception, design, deployment, acquisition, operation, maintenance, decommissioning, and disposal. (Note: This guideline refers to these stages as eight distinct phases: design, fabricate, install, commission, operate, maintain, change, and decommission.)
Lower Explosivity Limit (LEL)	See Lower Flammability Limit (LFL). (Note: This guideline refers to LFL, only.)
Lower Flammability Limit (LFL)	That concentration of a combustible material in air below which ignition will not occur. It is often, interchangeably called Lower Explosive Limit (LEL) and for dusts, the Minimum Explosible Concentration (MEC).
Maximum Credible Event (MCE)	A hypothetical explosion, fire, or toxic material release event that has the potential maximum consequence to the occupants under consideration from among the major scenarios evaluated. The major scenarios are realistic and have a reasonable probability of occurrence considering the chemicals, inventories, equipment and piping design, operating conditions, fuel reactivity, process unit geometry, industry incident history, and other factors. Each building may have its own set of MCEs for potential explosion, fire, or toxic material release impacts [API RP 752]. See Worst Case Scenario (WCS) or Alternative Release Scenario (ARS).
Mitigative Safeguard	A safeguard that is designed to reduce the severity of a loss event. Mitigative safeguards can be divided into detection safeguards and correction safeguards. See Safeguard.
Off-Site	Outside of the facility’s property line - represents the adjacent area external to the company’s boundary limits, with the “off-site consequences” representing the impact, if any, on industrial neighbors, the surrounding community or environment.
On-site	Inside the facility’s property line - the processes and support operations within the company’s boundary or property limits (this may be the “fence line” if the adjacent land is not owned by the company).
On-Site Personnel	Employees, contractors, visitors, service providers, and others present at the facility.
Permanent Building	Rigid structures intended for permanent use in fixed locations.
Piperack, Pipeway, Pipeband	A structure that supports pipes, power leads, and instrument cable trays.
Plant	See Facility.
Pool Fire	The combustion of material evaporating from a layer of liquid at the base of the fire.
Portable Building	Rigid structure that can be easily moved to another location within the facility. Portable buildings include temporary buildings or trailers used to house people or store equipment.
Preventive Safeguard	A safeguard that prevents the occurrence of a particular loss event, given that an initiating cause has occurred; i.e., a safeguard that intervenes between an initiating cause and a loss event in an incident sequence. See Safeguard.
Probit	A random variable with a mean of 5 and a variance of 1, which is used in various effect models. Probit-based models derived from experimental dose-response data, are often used to estimate the health effect that might result based upon the intensity and duration of an exposure to a harmful substance or condition (e.g., exposure to a toxic atmosphere, or a thermal radiation exposure).
Process Safety Hazard	See Hazard.
Process Section (or Train)	A “process section” or “train” is an area within a process unit containing combination of processing equipment that is focused on a single operation.
Property Line	The perimeter of a facility surrounded by the community, other industrial facilities, or undeveloped land owned by someone external to the company. Sometimes called a property boundary.
Quantitative Risk Analysis (QRA)	The systematic development of numerical estimates of the expected frequency and severity of potential incidents associated with a facility or operation based on engineering evaluation and mathematical techniques.
Risk Based Process Safety (RBPS)	The Center for Chemical Process Safety’s process safety management system approach that uses risk based strategies and implementation tactics that are commensurate with the risk based need for process safety activities, availability of resources, and existing process safety culture to design, correct, and improve process safety management activities.
Safeguard	Design features, equipment, procedures, etc. in place to decrease the probability or mitigate the severity of a cause-consequence scenario. Also known as a protective layer.
Safe Haven	A building or enclosure that is designed to provide protection to its occupants from exposure to outside hazards
Sheltering	Physical protection (such as an enclosed building) against the outcome of an incident.
Siting	The process of locating a complex, site, plant, or unit.
Stakeholder	Individuals or organizations that can (or believe they can) be affected by the facility’s operations, or who are involved with assisting or monitoring facility operation.
Structure	Something (such as a building, bridge or pipe rack) that is constructed to support equipment, piping, or personnel and is usually designed to stand on its own.
Tent	A term used to describe a wide range of structures, such as traditional tents with or without sides (a “canopy”), air inflated structures, air supported structures, tensioned membrane structures, scaffold structures, or structures that use a combination of fabric and rigid panels (API RP 756).
Turnaround	A scheduled shutdown period when planned inspection, testing, and preventative maintenance, as well as corrective maintenance such as modifications, replacements, or repairs are performed.
Utility	Supplies services to the facility such as electricity, instrument air, steam or heating medium, fuels (oil, gas, etc.), refrigeration, cooling water or cooling medium, or inert gases.
Vapor Cloud Explosion (VCE)	The explosion resulting from the ignition of a cloud of flammable vapor, gas, or mist in which flame speeds accelerate to sufficiently high velocities to produce significant overpressure.
Wind Rose Diagram	A plan view diagram that shows the percentage of time the wind is blowing in a particular direction. Often used as a symbol to indicate the "prevailing wind" direction (e.g., on a drawing or map).
Worst Case Scenario (WCS)	The basis for an off-site consequence analysis required by the EPA RMP Rule. This intentionally conservative accident scenario assumes the release of the entire inventory of a vessel, under the most unfavorable conditions, and with the failure of most protective features. See Maximum Credible Event (MCE) and Alternative Release Scenario (ARS).
Zone	Zone (per Article 500 of NFPA 70, National Electrical Code): The classification system for electrical and electronic equipment and wiring for all voltages in locations where fire or explosion hazards may exist. (Also the area defined through a “Hazardous Area Classification” (HAC).) Zone (per European electrical classification): The “zone” is equivalent to the “area” noted in Hazardous Area Classifications in the United States.

AIChE	American Institute of Chemical Engineers
AIHA	American Institute of Industrial Hygienists
ALARA	As Low As Reasonably Available
ALARP	As Low As Reasonably Practicable
AOTC	Associated Overseas Countries and Territories
API	American Petroleum Institute
ARS	Alternative Release Scenario
ASME	American Society of Mechanical Engineers
ATEX	European Directives 1999/92/EC and 2014/34/EU
BPCS	Basic Process Control System
BPV	Bursting Pressure Vessel
BSI	British Standards Institution
BST	Baker-Strehlow-Tang blast model
CCPS	Center for Chemical Process Safety
CFD	Computational Fluid Dynamics
CFR	United States Code of Federal Regulations
COMAH	United Kingdom HSE Control of Major Accident Hazards
CSB	United States Chemical Safety Board
DHA	Dust Hazards Analysis
DHS	United States Department of Homeland Security
DIN	Deutsches Institut für Normung
DOT	United States Department of Transportation
EN	European Union Standards
EPA	United States Environmental Protection Agency
ERPG	Emergency Response Planning Guidelines (AIHA)
EU	European Union
GB	China standards annotation
HAC	Hazardous Area Classification (electrical)
IChemE	Institution of Chemical Engineers
ISD	Inherently Safer Design
ISO	International Organization for Standardization
ITPM	Inspection, Testing, and Preventative Maintenance program
LEL	Lower Explosivity Limit
LFG	Liquefied Flammable Gas
LFL	Lower Flammability Limit
LNG	Liquefied Natural Gas
LPG	Liquefied Petroleum Gas
MEC	Minimum Explosible Concentration (i.e., combustible dusts)
MCE	Maximum Credible Event
NFPA	National Fire Protection Agency
OSHA	United States Occupational Safety and Health Administration
PED	Pressure Equipment Directive
POTW	Publically Owned Treatment Works
PSM	Process Safety Management
PSS	Process Safety System
RBI	Risk Based Inspection program
RBPS	Risk Based Process Safety
RCM	Reliability Centered Maintenance
RCRA	Resource Conservation and Recovery Act (United States EPA)
RMP	Risk Management Program (United States EPA)
RP	Recommended Practice (i.e., API guidance)
UK	United Kingdom
UK HSE	United Kingdom Health and Safety Executive
US	United States
VCE	Vapor Cloud Explosion
WCS	Worst Case Scenario

Martin Timm	Chair, Praxair
Don Connolley	Vice Chair, BP
Susan Bayley	Linde
Chris Buchwald	ExxonMobil
Bruce Bullough	Corden Pharma (Retired)
Andrew Carpenter	Exponent
Andy Crerand	Shell
Chris Devlin	Celanese
Randy Hawkins	Philips66
Dave Herrmann	DuPont (Retired)
Manuel Herce	DuPont
David Hill	OxyChem (Retired)
Casey Johnson	Bayer / Covestro
Jayant Kulkarni	Aon
Bill Lindberg	Air Liquide
Reid McPhail	CNRL
Tim Murphy	Arkema
Pamela Nelson	Cytec
Eric Peterson	MMI Engineering
Ray Qi	Huntsman
Mark Saunders	Koch Industries
Florine Vincik	BASF
Jonas Duarte	Chemtura
Charles Cowley	CCPS Staff Consultant

Jordi Costa Sala	Celanese
Curtis Clements	Chemours
Cheryl Grounds	BP; Co-author of the 2003 Edition
Michael Hiam	BP
Pete Lodal	Eastman
Louisa Nara	CCPS
Keith Noll	Cytec
John Remy	Lyondell-Basel
Renato Sampaio	Dow
Jan Windhorst	Nova Chemicals (Retired); peer reviewer of 2003 Edition

GUIDELINES FOR SITING AND LAYOUT OF FACILITIES

CENTER FOR CHEMICAL PROCESS SAFETY OF
THE
AMERICAN INSTITUTE OF CHEMICAL
ENGINEERS
New York, NY

Acronyms and Abbreviations

Glossary

Acknowledgments

Foreword

Preface

CENTER FOR CHEMICAL PROCESS SAFETY OF THE AMERICAN INSTITUTE OF CHEMICAL ENGINEERS New York, NY

CENTER FOR CHEMICAL PROCESS SAFETY OF
THE
AMERICAN INSTITUTE OF CHEMICAL
ENGINEERS
New York, NY