Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 59
4
The Concepts of Inherently Safer Processes
and Assessment
INTRODUCTION
The committee was asked to consider the processes used by Bayer Crop -
Science to manufacture methyl isocyanate (MIC) and carbamate pesticides in
Institute, West Virginia, and compare its analysis to “the inherently safer process
assessments conducted by Bayer and previous owners of the Institute site.”
Whereas the preceding chapter provided an overview of the plant and its history
to provide background on the development of the processes, this chapter provides
an overview to the concept of inherently safer processes (ISPs) and describes the
role of ISPs in a process safety management (PSM) system as background for
the analysis of the decisions made during those developments. Chapter 5 contains
the analysis of alternative methods for production of MIC and the carbamate
pesticides produced in Institute, including consideration of ISPs. This chapter
also provides an introduction to the role that ISP analyses can play in decision-
making. More information about the broader context in which companies manage
decision making, and a suggested framework for approaching that process in
complex scenarios, is presented in Chapter 6.
THE ISP CONCEPT
ISP is best described as a philosophy for engineering design of material
processing plants, rather than a specific set of technologies or processes. The ISP
philosophy can be applied at all stages in the life cycle of a manufacturing plant,
from early process invention and research, through development, plant design,
operation, and eventual shutdown and demolition, and at all levels of design detail.
59
OCR for page 59
60 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
It is an approach that encourages the designer to attempt to eliminate or minimize
hazards (physical, inhalational, etc.) identified at each stage in the process life
cycle, and at every level of process and plant design, rather than accepting the
existence of the hazards and designing safety systems to control those hazards. It
may not always be feasible to eliminate or reduce hazards, but the ISP philosophy
requires that this be attempted before moving on to specification of risk manage-
ment equipment and procedures. Note that describing a process as “inherently
safer” can only be done in the context of specific hazard or subset of hazards and
that management of all hazards must be considered in order to design a safer
process. Thus, a substitution (inherent) might eliminate one type of hazard but
require the development of new standard operating procedures (procedural) to
manage a different one.
The terms “inherently safer processes” (ISPs),1 and variations such as “inher-
ently safer technology” (IST) and “inherently safer design” (ISD) were first used
in discussions about PSM in the 1970s after serious process industry incidents
around that time.2 These incidents focused industry, government, and public
attention on PSM, and resulted in the initial development of many of the PSM
techniques and regulations that are in common use throughout the world today.
The ISP philosophy was first fully articulated in 1977 by Trevor Kletz, a
senior safety advisor for Imperial Chemical Industries (ICI). That year Kletz
presented the Jubilee Lecture to the Society of Chemical Industry in Widnes,
England, which he titled “What you don’t have, can’t leak.” In his talk, Kletz
challenged the practice of storing large quantities of flammable or toxic mate -
rials at manufacturing plants and questioned the need for the use of elevated
temperatures and pressures in processing (Kletz, 1978). He also suggested that
risk management efforts should aim at elimination of hazards where feasible,
instead of using safety systems and procedures to manage the risk. This should
be accomplished, for example, by reducing the amounts of hazardous material
used in processes, using less-hazardous materials, or developing technology that
allows for processes to proceed under milder conditions. Kletz described this as
“inherently safer.”3
In subsequent years, a set of principles for ISPs were established within the
chemical community, an effort supported by Kletz (1984, 1985, 1991, 1998) and
others in the chemical industry (Puranik et al., 1990; Ashford, 1993; Windhorst,
1995; Mannan, 2005; See also additional references at the end of this chapter). As
1 The term “inherently safer processes” is used here in accordance with the language of the state -
ment of task.
2 These included a 1974 explosion at a chemical plant in Flixborough, England that resulted in the
deaths of 28 and injuries to another 36 individuals and a 1976 chemical release at Seveso in Milan,
Italy that sickened many in the surrounding area.
3 In his 1977 lecture, Kletz used the term “intrinsically safer.” This was later changed to “inherently
safer” to avoid confusion with the use of “intrinsically safe” to describe electrical equipment designed
to meet specific hazardous area classification requirements.
OCR for page 59
61
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
the principles spread and were adopted, many examples of their implementation
emerged. The Center for Chemical Process Safety (CCPS) aggregated this infor-
mation in the book Inherently Safer Chemical Processes: A Life Cycle Approach
(Bollinger et al., 1996; CCPS, 2008b). The early versions focused primarily on
general concepts, but as acceptance of ISPs by the professional community has
grown, the later versions extended the scope to provide more specific guidance
on application of those concepts to process design. Today there are a number of
working definitions of ISPs, some of which are presented in Box 4.1. In general,
these definitions are quite consistent and reflect a consensus of the engineering
community on what ISP means.
BOX 4.1
Definitions of Inherently Safer Processes
CCPS (2008b, p. 11). “Inherent safety is a concept, an approach to
safety that focuses on eliminating or reducing the hazards associated
with a set of conditions. A chemical manufacturing process is inherently
safer if it reduces or eliminates the hazards associated with materials
and operations used in the process and this reduction or elimination is
permanent and inseparable. The process of identifying and implementing
inherent safety in a specific context is called inherently safer design. A
process with reduced hazards is described as inherently safer compared
to a process with only passive, active, and procedural controls. An inher
ently safer process should not, however, be considered ‘inherently safe’
or ‘absolutely safe.’ While implementing inherent safety concepts will
move a process in the direction of reduced risk, it will not remove all risks.
No chemical process is without risk, but all chemical processes can be
made safer by applying inherently safer concepts.”
Kletz and Amyotte (2010, p. 4). “Intensification, substitution, attenua
tion, and limitation of effects produce inherently safer design because
they avoid hazards instead of controlling them by adding protective
equipment. The term inherently safer implies that the process is safer
because of its very nature and not because equipment has been added
to make it safer. Note that we talk of inherently safer plants, not inherently
safe ones, for we cannot remove all hazards.”
State of New Jersey and Contra Costa County, California. New
Jersey, in its Toxic Catastrophe Prevention Act (TCPA) (NJDEP, 2009),
and Contra Costa County, California, in its Industrial Safety Ordinance
continued
OCR for page 59
62 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
BOX 4.1 Continued
(Contra Costa Health Services, 1999), require consideration of ISPs as
part of their regulation of hazardous industrial facilities. Both regulations
cite the 1996 CCPS definition of ISP (Bollinger et al., 1996) (the regula
tions were issued before publication of the second edition of the CCPS
book), which is substantially the same as the 2008 definition above,
although not as concisely stated.
U.S. Department of Homeland Security/CCPS. The U.S. Department of
Homeland Security (DHS), concerned about the potential for intentional
release of hazardous materials by terrorist attack, has been interested in
ISP as an approach to chemical security. In 2010, the Chemical Security
Analysis Center of DHS asked the CCPS to develop a scientific definition
of IST (CCPS, 2010, p. Exec 1). A summary of that definition is:
Inherently Safer Technology (IST), also known as Inherently Safer Design
(ISD), permanently eliminates or reduces hazards to avoid or reduce the
consequences of incidents. IST is a philosophy, applied to the design
and operation life cycle. . . . IST considers options, including eliminating
a hazard, reducing a hazard, substituting less hazardous material, using
less hazardous process conditions, and design a process to reduce the
potential for, or consequences of, human error, equipment failure. . . . IST’s
are relative. A technology can only be described as inherently safer when
compared to a different technology, including a description of the hazard
or set of hazards being considered, their location, and the potentially
affected population. . . . IST’s are based on an informed decision process.
Because an option may be inherently safer with regard to some hazards
and inherently less safe with regard to others, decisions about the optimum
strategy for managing risks from all hazards are required. The decision
process must consider the entire life cycle, the full spectrum of hazards
and risks, and the potential for transfer of risk from one impacted popula
tion to another.
HIERARCHY OF HAZARD CONTROL
PSM is an interactive, ongoing method for controlling hazards across a
facility or organization, with the overall goal of reducing the frequency and/or
consequence of an incident. As described in Chapter 2, within the United States,
requirements for PSM exist under the Occupational Health and Safety Administra-
tion’s (OSHA) process safety management standard (OSHA, 29 CFR 1910.119).
The PSM standard lists 14 mandatory elements ranging from employee training
to process hazard analysis to change management. In practice, PSM is a system
OCR for page 59
63
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
that necessitates consideration of multiple options for achieving a safe process
and the possible outcomes from each of those options. For example, when deter-
mining which hazard management strategy is the best option for a given situation,
it is important to understand the effect that any one change in process design may
have on all classes of hazard and how that change may affect the type of control
strategy required to maintain a safe working environment.
One approach for acknowledging and addressing these trade-offs is to con -
sider a hierarchy of hazard control. The hierarchy contains four tiers, inherent,
passive, active, and procedural, which are described briefly below.4,5 Consider-
ing these possible hazard control methods in turn can help identify options for
process design or modifications to improve process safety.
Inherent
The inherent approach to hazard control is to minimize or eliminate the
hazard. Substituting water for a flammable solvent to eliminate the fire hazard
is an example. CCPS identifies four ISP strategies to consider when designing
or modifying a process (CCPS, 2008b). As adapted from that volume, one can:
Substitute—use materials, chemistry, and processes that are less hazardous;
Minimize—use the smallest quantity of hazardous materials feasible for the
process, reduce the size of equipment operating under hazardous conditions, such
as high temperature or pressure;
Moderate—reduce hazards by dilution, refrigeration, process alternatives
that operate at less-hazardous conditions; reduce potential impact of an accident
by siting hazardous facilities remotely from people and other property; or
Simplify—eliminate unnecessary complexity, design “user-friendly” plants.
Kletz and Amyotte (2010, pp. 16-17) use somewhat different terminology
and identify more specific categories (which can be mapped into the four CCPS
categories above), but the basic philosophy remains the same. As stated in that
reference:
One person’s intensify may be another’s minimize. Someone’s attenuate may
be someone else’s moderate. You may wish to consider segregate as a measure
4 As with the terminology regarding inherent safety categories, these classifications fall along a
spectrum of process safety approaches, and people may disagree about the category into which a par-
ticular design falls. For example, some might consider that a high pressure reactor design capable of
containing a runaway reaction is an inherently safer design. Others would call this a passive strategy
because the hazard—the high pressure from the runaway reaction—still exists, although it is robustly
contained by a high pressure vessel.
5 Not that the use of these terms is not limited to chemical process safety but are also used in
consideration of nuclear facility design and management.
OCR for page 59
64 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
separate from inherent safety; your colleague may consider it a form of limita-
tion of effects….the characteristics of a user-friendly plant are sometimes not
sharply divided and may merge into one another. Process design, like life, is
seldom linear.
The following definitions will be familiar to many in the process industry.
These have been summarized and adapted from the 2008 publication Inherently
Safer Chemical Processes: A Life Cycle Approach, 2nd Edition from the AIChE
Center for Chemical Process Safety, and similar definitions can be found in many
reference texts on process safety.
Passive
Passive safety systems are those that control hazards with process or equip -
ment design features without additional, active functioning of any device. For
example, a containment dike around a hazardous material storage tank limits a
spill to an enclosed area because of the geometry and construction of the dike,
and no action is required to provide this function.
Active
Active safety systems control hazards through controls and systems designed
to monitor and maintain specific conditions or to be triggered by an event. Active
systems include process controls, safety instrumented systems (SIS), and mitiga -
tion systems. A sprinkler system put in place to extinguish a fire is an example
of an active system designed to minimize consequences. A control system that
regulates solvent flow into a reactor vessel and prevents overflow is an example
of a monitoring system.
Procedural
Procedural safety systems control hazards through personnel education and
management. Such systems include standard operating procedures, safety rules
and procedures, operator training, emergency response procedures, and manage -
ment systems. For example, an operator may be trained to monitor the solvent
level in a reactor vessel and to shut off the feeds to the tank if the volume exceeds
a given quantity.
In general, inherent and passive strategies are the most robust and reliable,
requiring the least monitoring or interaction to be effective, but incorporation of
strategies from all tiers of the hierarchy should be considered and incorporated
as needed for comprehensive PSM. Note that all process safety controls have
the potential to reduce the probability or likelihood that a worst-case accident
OCR for page 59
65
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
occurs. However, the incorporation of ISP concepts into process design also has
the potential to provide assurance that, should a worst-case release occur (i.e.,
the entire chemical inventory under worst meteorological conditions), an absolute
upper bound to the magnitude of an offsite release exists, and that this upper
bound is less severe than the worst-case accident resulting from conventional
passive, active, and procedural controls.
When performing a process safety assessment, one should consider each
level of this process safety “hierarchy” in turn. Quite logically, if the hazard can
be controlled with a system that emphasizes inherent safety, active controls will
not be necessary. However, since ISP is defined in the context of a specific hazard,
the risk of introducing new hazards must be considered. For example, one can
describe a process alternative as inherently safer with respect to the acute toxicity
of a particular raw material when compared with another alternative. This state -
ment does not say anything about the relative inherent safety characteristics of
the two processes with respect to other hazards (fire, explosion, reactive chemis -
try, chronic toxicity, environmental impact, etc.). These hazards may be greater,
reduced, or remain essentially unchanged between the two process alternatives,
and the ISP for one hazard may also introduce new concerns.
Thus, it will always be necessary for process plant designers and operators
to develop rigorous PSM systems incorporating the appropriate combination of
inherent, passive, active, and procedural safety systems to manage all hazards.
Some will be best managed using inherent methods, but others will inevitably
remain and be effectively managed with other PSM systems. One must never
assume that it is unnecessary to worry about all elements of PSM because one
“inherently safer” process has been implemented.
INCORPORATING ISP INTO THE PROCESS LIFE CYCLE
The philosophy of ISP applies at all stages, but available options, or the
feasibility of implementing those options, change over the course of a tech-
nology’s life cycle. Every life cycle begins with initial research and product/
process conception, and then moves through process development, conceptual
plant design, scaleup, engineering and detailed plant design, plant construction,
startup, and ongoing operation and future modification (Hendershot, 2011a,b).
In each of these phases, different kinds of choices and decisions are made by
chemists, engineers, and other technologists. Both the second edition of the CCPS
book, Inherently Safer Chemical Processes: A Lifecycle Approach and the recent
volume by Kletz and Amyotte contain examples of how such analyses can be
incorporated into a process hazard analysis, including examples from industry,
and each contains additional citations for more information. These descriptions
will not be reproduced here. The purpose of this section is not to provide a step-
by-step description of how such analyses can be done, but to provide the reader
OCR for page 59
66 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
with a broad overview of the elements of the analysis as context for the rest of
the report.
There is potential synergy between process simulation and understanding ISP
characteristics of a process. Process simulation is a mathematical representation of
industrial chemical processes, often used in process design, control, and optimiza -
tion. Simulations assist engineers in evaluating process alternatives and to identify
possible options to, for example, reduce energy consumption, minimize waste,
perform cost and benefit studies, and maximize profitability. These tools provide
information about process operating conditions and inventory in-process equip-
ment, both of which are important factors in understanding ISP. It may be possible
to more explicitly incorporate ISP considerations into process simulation tools,
e.g., the inventory of hazardous materials for different process options. Linking
process simulation models to accident consequence and likelihood models would
have the potential to facilitate the investigation of potential benefits of process
alternatives being studied.
It is clear that the best opportunity for implementing ISP into a facility is
early in the life cycle of a product or process. At that early stage, process tech-
nologies have not been chosen, facilities have not been built, and customers have
not yet evaluated product samples or made commitments based on products with
particular characteristics. As a product moves through its life cycle, these and
other factors may limit options, make changes more difficult, or involve more
people and organizations in the change. Development of an ISP, as with the devel-
opment of any new process, requires extensive resources, including for example,
expert personnel, laboratory facilities, pilot plant facilities, and significant finan -
cial expenditures, and modifications can become more costly when the process
involves modification of an existing facility.
Some typical process life-cycle stages and some examples of ISP options that
are best considered at an early stage include:
• Selection of basic technology. Consider ISP options for the chemical
synthesis route, raw material and chemical intermediate hazards, energetic reac -
tions, etc.
• Implementation of the selected technology. Consider how the chosen
process chemistry will be implemented. Can hazardous operating conditions be
minimized through better catalysts or other changes in operating conditions?
Can impurities and by-products be avoided to eliminate purification steps? What
specific unit operations are required? What is the order of processing steps?
• Plant design. Consider ISP aspects of plant proximity to the surrounding
population, in-plant occupied areas, and sensitive environmental areas; the gen -
eral layout of the equipment on the selected plant site; and the number of parallel
systems and size of those system (Hendershot, 2010a).
• Detailed equipment design. Minimize the inventory of hazardous mate-
rial in specific pieces of process equipment. Consider the impact of equipment
OCR for page 59
67
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
layout on the length and size of piping containing hazardous materials. Consider
human factors in the design of equipment to minimize the potential for incorrect
operation and human error (Hendershot, 2010a).
• Operation. Use ISP principles on ongoing PSM activities such as man-
agement of change, incident investigation, pre-startup safety reviews, operating
procedures, and training to identify new opportunities for ISP.
It is important to consider the entire footprint of a process when evaluating
ISP options. Is risk actually reduced, or is it transferred somewhere else, perhaps
increasing overall risk? One example used to demonstrate this concept relates
to the balance of onsite storage versus increased deliveries of hazardous mate -
rial (Hendershot, 2006; CCPS, 2010). If a plant reduces the size of a hazardous
material storage tank, would the smaller tank size require a change from shipment
of the material to the plant in railroad tank cars to much smaller trucks? Such a
change could then result in a greater number of shipments overall to meet process
requirements (one rail car can hold approximately an order of magnitude more
material than a truck). With the additional shipments traveling by road instead
of rail, the change in storage tank size could result in greater overall risk from
release, depending on details of the transportation route.
It is also important to recognize that an ISP assessment is often not going
to result in a clear, well-defined, and feasible path forward for a company. It is
a useful philosophy that can help a company reduce its risk and provide struc -
ture for consideration of the full range of options in process design. The results
of any analysis, however, have to be considered in context. For example, as
already described, the inherent safety of one hazard may be reduced and another
increased depending on size of a shipment or the mode of transportation of the
shipment, or risk may shift from one community well equipped to respond to an
emergency to one less able to do so. The cost to eliminate a hazard completely
may be prohibitive, but introducing a well-designed passive control system may
be feasible. Consideration of these and other, broader trade-offs (community
perception, product quality requirements, etc.) should be factored into any final
decision.
ADDITIONAL CONSIDERATIONS
As stated in Manuele (2003), “An organization’s culture consists of its values,
beliefs, legends, rituals, mission, goals, performance measures, and sense of
responsibility to its employees, to its customers, and to its community, all of which
are translated into a system of expected behavior.” When the philosophy of ISP
is incorporated into the culture of an organization, it becomes one of the cultural
norms that guide behavior within that organization. Consideration of ISP can then
be incorporated into all process and design activities rather than being considered
an additional check-the-box exercise.
OCR for page 59
68 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
CCPS (2008) highlighted elements within organizations that can encourage
successful adoption of ISP as part of the organizational culture. The first of these
is integration of ISP into the PSM system. This should include consideration
of ISP at all stages in the process life cycle, particularly at three key stages:
product and process development, conceptual facility planning and early design,
and during routine operation (including modifications and incident investigation).
The second element is education and awareness. ISP is a philosophy of design;
its application should extend beyond just engineering design to plant operation
activities. Identifying opportunities to eliminate or reduce hazards should be
part of the job for everyone involved in the design and operation of a process
facility. This can only happen if there is a broad awareness and understanding
of ISP concepts and principles, and these require that education and supporting
documentation be made available to personnel.
RELATIONSHIP BETWEEN EMERGENCY PREPAREDNESS AND ISP
Emergency preparedness (EP is often considered to be an alternative to
ISP strategies because EP is a procedural control). However, as is the case
with active, passive, and other procedural controls (e.g., personnel training), EP
can—and should—be implemented concurrently with ISP, e.g., where Horng
et al. (2005) recommended combining source reduction with warning systems
to reduce chlorine risks in Taiwan. A closer examination reveals that EP and
ISP are closely linked because the latter can be used to reduce the magnitude
of incident demands on the onsite and offsite emergency response organizations
by reducing the size of the vulnerable zones (VZs) around chemical facilities.
Specifically, applying ISP principles to the EPA (1987) procedure for calculating
VZs shows that substitution decreases VZ size by reducing source toxicity (i.e.,
level of concern), whereas minimization achieves this objective by reducing the
quantity available for release, and moderation reduces VZ size by decreasing the
temperature and pressure of a release.
Smaller VZs reduce the demands on the emergency response organizations
by reducing the size of the population at risk. Of particular importance is the
fact that smaller VZs often mean that there are smaller special populations at
risk—such as residents of schools, hospitals, nursing homes, jails, and athletic
stadiums (see Lindell and Perry, 2006, Table 1, for a list of special facilities).
Special populations generally have more logistical impediments to implementing
population protection actions such as evacuation (Van Willigen et al., 2002) and,
probably to a lesser extent, sheltering in-place (Sorensen et al., 2004).
Although the adoption of ISP strategies can have a positive effect on nearby
offsite risks, it is important to recognize that they can have a negative effect
on more remote offsite risks by transferring rather than reducing total risk (see
CCPS, 2008b, p. 212). This risk transfer occurs when reducing onsite chemical
inventory has the unintended consequence of increasing the number of shipments
OCR for page 59
69
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
and thus increasing the probability of releases on transportation routes. This can
have an adverse impact on emergency response because releases from onsite
sources, by their very nature, take place at locations where they are expected to
occur and where there are (relatively) ample resources for emergency response.
Releases during transportation, by contrast, take place at unexpected locations
where there are likely to be fewer resources to support an emergency response.
For example, the sites of transportation incidents will lack the detection and
monitoring systems that are often installed around fixed-site facilities. Moreover,
the primary responders to transportation incidents will be public sector hazardous
materials response teams that are likely to have a relatively limited knowledge of
any given chemical, given that hundreds of chemicals might pass through their
jurisdictions. By contrast, facility personnel often handle only a few chemicals
and thus usually have a deeper knowledge of these chemicals’ characteristics and
behavior.
Additional information about the relationship between ISP and emergency
response and emergency preparedness can be found in Appendix C.
OPTIONS FOR INCORPORATING ISP IN PSM
There are two common approaches to formal consideration of ISP: inde -
pendent, stand-alone ISP reviews and incorporation of ISP into existing process
safety review activities.
Independent ISP Reviews
An independent ISP review is conducted by a team that uses knowledge of
chemistry, engineering, operation, process safety, and other relevant expertise to
examine a process with the objective of understanding its hazards and finding
ways to eliminate or reduce those hazards. The review can be done at any stage in
the process life cycle from early product and process development through oper-
ating facilities. The more established the process, the more difficult and costly
it becomes to take advantage of ISP opportunities involving the basic process
technology. Thus, early consideration of ISP in product and process selection is
important. Major renovation of established facilities also provides an opportunity
to reevaluate the basic process technology from an ISP perspective.
The most important tool for an ISP review is an extensive checklist to help
the team think about strategies and how they might apply to the process being
considered. ISP reviews can draw upon any of the traditional process safety
review techniques (e.g., HAZOP,6 What If, and Checklists) to identify hazards,
6 HAZOP (Hazard and Operability Analysis) is a method of systematic evaluation of existing pro -
cesses and operations developed for process hazard analysis and commonly used within the chemical
industry.
OCR for page 59
72 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
TABLE 4.1 Examples of Development of ISP Assessment Methodologies and
Their Application and Extension, 2002-2010
Reference Contribution
Adu et al. (2008) Comparative evaluation of various methods for assessing EHS
hazards in early phases of chemical process design.
Al-Mutairi et al. (2008) Linking of inherent safety and environmental concerns with
optimization of process scheduling.
Carvalho et al. (2008) Method for identifying retrofit design alternatives of chemical
processes. Uses Inherent Safety Index (ISI) developed by
other researchers.
Cordella et al. (2009) Further development of procedure for decomposition product
analysis (Cozzani et al., 2006) to account for acute and
long-term harm to human health, ecosystem damage, and
environmental media contamination.
Cozzani et al. (2006) Procedure for assessment of hazards arising from
decomposition products formed due to loss of chemical
process control. Applicable to consideration of substitution
principle.
Gentile et al. (2003) Fuzzy-logic-based index for evaluation of inherently safer
process alternatives with the aim of linking to process
simulation.
Gupta and Edwards (2003) Graphical approach for evaluating inherent safety based on
earlier developed Loughborough Prototype Index of Inherent
Safety (PIIS).
Hassim and Hurme (2010a) An Inherent Occupational Health Index was developed to
assess the health risk of process routes during the process
research and development stage. The index can be used to
compare process routes or to determine the level of inherent
occupational health hazards.
Hassim and Hurme (2010b) The Health Quotient Index (HQI) was developed for
assessment during the preliminary process design phase.
This index quantifies a worker’s health risk from exposure to
fugitive emissions by using data from process flow diagrams.
This method can be used to quantify the level of risk from a
process or to compare alternative processes.
Hassim and Hurme (2010c) The Occupational Health Index (OHI) was developed
for assessment during the basic engineering stage. “This
method relies on the information available in piping and
instrumentation diagrams and the plot plan.” The health
aspects considered are chronic and acute inhalation risks, and
dermal/eye risk.
Hassim and Hurme (2010d) This method estimates inhalation exposures and risks and can
be used early in the design stages by utilizing process flow
diagrams. The risk of chemical exposure can be evaluated
through either the “hazard quotient method or calculating
the carcinogenic chemicals intake and the resulting risk of
cancer.”
OCR for page 59
73
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
TABLE 4.1 Continued
Reference Contribution
Hassim and Edwards (2006) Process Route Healthiness Index (PRHI) for quantification
of health hazards arising from alternative chemical process
routes. Application is in early stages of chemical plant design.
Hurme and Rahman (2005) Discussion of implementation of inherent safety throughout
process life-cycle phases. Use of ISI developed earlier.
Khan and Amyotte (2004) Integrated Inherent Safety Index (I2SI).
Khan and Amyotte (2005) Further development of I2SI to include cost model.
Kossoy et al. (2007) Use of nonlinear optimization method to select inherently
safer operational parameters for given configuration of reactor
equipment and materials. Primary concern is cooling failure.
Landucci et al. (2007) Procedure and indexes for evaluating inherent safety at
preliminary process flow diagram (PFD) stage for hydrogen
storage options.
Landucci et al. (2008) Further development of PFD method (Landucci et al., 2007)
by use of quantitative key performance indicators (KPIs) to
remove subjective judgment.
Leong and Shariff (2008) Further development of iRET (Shariff et al., 2006) to
incorporate a quantitative inherent safety level (ISL), thus
enabling integration of design simulation software with an
Inherent Safety Index Module (ISIM). Application is again at
the preliminary design stage.
Leong and Shariff (2009) Evolution of ISIM (Leong and Shariff, 2008) to a Process
Route Index (PRI) for comparison and ranking of different
routes to manufacture the same product based on hazard
potential of routes.
Meel and Seider (2005) Use of game theory to achieve inherently safer operation of
chemical reactors.
Palaniappan et al. (2002a) “Methodology for the integrated inherent safety and waste
minimization analysis during process design.”
Palaniappan et al. (2002b) Indexing procedure for inherent safety analysis at process
route selection stage.
Palaniappan et al. (2002c) Indexing procedure for inherent safety analysis at process
flowsheet development stage. Discussion of iSafe, an expert
system for automating procedures developed by Palaniappan
et al. (2002b,c).
Rahman et al. (2005) Comparative evaluation of three ISIs with expert judgment at
process concept phase.
Rusli and Shariff (2010) This paper presents the Qualitative Assessment for Inherently
Safer Design (QAISP) method for application during
preliminary design. This qualitative method combines hazard
review techniques with inherently safer design concepts to
generate inherently safer plant options/proactive measures.
Shah et al. (2003) SREST (substance, reactivity, equipment, and safety
technology) layer assessment method for environment, health,
and safety (EHS) aspects in early phases of chemical process
design.
continued
OCR for page 59
74 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
TABLE 4.1 Continued
Reference Contribution
Shariff and Leong (2009) This paper proposes a method of evaluating inherent risk
within a process as a result of the chemicals used and the
process conditions. Through integration with HYSYS, the
method can be used as early as the initial design stages to
determine the probability and consequence of possible risk
due to major accidents.
Shariff and Zaini (2010) This paper reports on the development of Toxic Release
Consequence Analysis Tool (TORCAT), a “tool for
consequence analysis and design improvement via inherent
safety principle by utilizing an integrated process design
simulator with toxic release consequence analysis model.”
Shariff et al. (2006) Integrated Risk Estimation Tool (iRET) for inherent safety
application at preliminary design stage. iRET links the design
simulation software HYSYS with an explosion consequence
model.
Srinivasan and Kraslawski (2006) Application of TRIZ methodology for creative problem
solving to design of inherently safer chemical processes.
Srinivasan and Nhan (2008) Inherent Benign-ness Indicator (IBI), a statistical-analysis-
based method for comparing alternative chemical process
routes.
Tugnoli et al. (2009) A quantitative inherent safety assessment method is presented.
This method utilizes process flow diagrams in early design
stages. The result of the assessment is a quantification of
the inherent safety of the process scheme by a set of key
performance indicators.
SOURCE: Adapted from Kletz and Amyotte (2010) and supplemented with additional citations from
the literature from late 2009-2010.
• Many of the methods deal specifically with the early concept and route-
selection stages of the design process.
• Some of the approaches use sophisticated mathematical and problem-
solving techniques such as fuzzy logic.
• There has been a growing trend to link inherent safety with environmental
and health issues in an effort to achieve an integrated approach.
• There have been attempts to incorporate inherent safety assessment into
process design simulators, and these efforts should be encouraged.
• Some of the indexing methods have been in existence long enough for
comparative evaluations to be made among them.
When commenting in 2005 on potential barriers to wider adoption of inher-
ently safer design principles in the process industries, Edwards (2005) noted that
the issue may not be the availability of ISP assessment tools but rather the limited
use of these tools by industry. Reasons might include the subjective judgment
OCR for page 59
75
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
required by some of these tools and also their attendant complexity (Kletz and
Amyotte, 2010). In 2011, it appears that the same availability of tools, yet limited
uptake by industry, exists. Additional concerns surround the incorporation of
ISP and PSM analysis into the business decisions a company must make. This is
discussed in greater detail in Chapter 6.
Another approach that considers some important aspects of ISP, is conse-
quence analysis of potential incidents. Estimates of the potential impact of an
incident will include evaluation of the effect of inventory of hazardous material,
flammable and toxic properties, plant operating temperatures and pressures, plant
location, and other factors. Designers considering ISP alternatives for a process
can model consequences associated with potential design options and understand
whether the proposed ISP options have a significant impact on incident conse -
quences. However, modeling and evaluating potential probabilities and impacts
of system failures (worst-case accidents) can present their own challenges, espe -
cially with regards to modeling human behavior. This can lead to flawed evalu-
ations in terms of emergency response and risk communication needs. This is
described in greater detail in Box 4.2.
BOX 4.2
ISP and Probability Safety Analysis
Assessments about the safety of systems comprising conventional
active, passive, and procedural controls are typically based on probabi
listic safety analyses (PSAs) that estimate the probability of a worstcase
accident from three inputs. These are (1) a probabilistic safety model
(e.g., a mathematical model such as a fault tree or event tree) that iden
tifies the events, such as process component and engineering safety
feature (ESF) failure, that are required to produce a release; (2) the esti
mated probabilities of those events; and (3) the logical interrelationships
among those events. The probabilistic safety model is used to combine
the estimated probabilities of the individual events (component or ESF
failure) to produce the estimated probability of the worstcase accident.
Once a probabilistic safety model has been developed, it can be
used to compare the accident probabilities associated with different
plant/process designs. Ultimately, the mathematical model is often used
to determine when the probability of the worstcase accident has been
decreased to a level that is acceptable to plant management. However,
it is important to recognize that any mathematical model is a simplifica
tion of reality that ignores factors the analyst considers to have minimal
effects on the probability of an offsite release. In addition, probabilistic
continued
OCR for page 59
76 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
BOX 4.2 Continued
safety models sometimes ignore factors for which there are no available
data or for which there is no established procedure for including them in
the analysis.
One common problem in probabilistic safety models is that they are
applied to systems composed of both people and technical systems but
only the technical (equipment) components are modeled. This problem is
being addressed in techniques that address human reliability (e.g., Swain
and Guttman, 1983; Gertman et al., 2005; Spurgin, 2010) but human
reliability is not always considered in plant PSAs.
Another common problem in probabilistic safety models is that the
builders of the model often assume that the events in the model are
independent. This assumption is violated when a common cause can
fail multiple process components or ESFs, such as when an earthquake
simultaneously fails a pipe carrying a toxic chemical, the secondary con
tainment for that pipe, the flare tower, and the water curtain. Less obvi
ously, the independence assumption is violated when a single operator
fails to properly control multiple ESFs, a single maintenance person fails
to properly maintain multiple ESFs, a single manager fails to properly
supervise multiple operators or maintainers, or when an organizational
unit’s safety culture tolerates inadequate performance. Such dependen
cies could be included in the model, but often this is not done.
The neglect of human reliability and event dependence in probabilistic
safety models leads to systematic underestimates of incident probabili
ties. However, such underestimates will not create significant problems
when two system designs being compared that are very similar in their
susceptibility to human error and commoncause failures. This is be
cause in such cases comparison of similar system designs by subtraction
of the failure probability of one system from the failure probability of the
other yields the correct difference even if both of the absolute estimates
are biased. For example, suppose the estimated failure probability for
System 1 is PE1 (which equals PT1 PB, where PT1 is the true failure
probability for System 1 and PB is the bias due to omitted error causes)
and, similarly, the estimated failure probability for System 2 is PE2 (which
equals PT2 PB, where PT2 is the true failure probability for System 2 and
PB is again the bias due to omitted error causes). The difference between
the estimated failure probabilities for the two systems is unbiased as
long as the omitted error causes are the same in both systems because
PE2 PE1 = (PT2 PB) – (PT1 PB) = PT2 PT1. The difference between
the estimated failure probabilities for the two systems is unbiased as
long as the omitted error causes are the same in both systems because
PE2 PE1 = (PT2 Pe) – (PT1 Pe) = PT2 PT1. By contrast, the absolute esti
OCR for page 59
77
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
mates of failure probability (i.e., the differences of PE2 and PE1 from zero)
are biased to the extent that failure causes have been omitted from the
probabilistic safety model. This illustration explains why it is so important
to compare probabilistic safety analyses of (relatively) similar systems
and to be very skeptical of estimates of absolute failure probabilities.
Unless the failure modes for both systems are identical, the bias in each
estimate may not be the same in which case the probability models may
not be useful even for comparing alternative systems unless they are
corrected to account for commoncause failures and human errors.
One consequence of underestimating the failure probability of a con
ventional system of active, passive, and procedural controls is that such
underestimates make ISP strategies seem to be less advantageous
than they would be if the failure probability of a conventional system of
active, passive, and procedural controls were accurately estimated. If
the magnitude of the underestimate were known to be small, then there
would be little reason to be concerned about it. However, the magnitude
of the underestimate is not known, but the evidence from published post
accident investigations suggests that it might be sufficiently large that
conventional strategies of active, passive, and procedural controls are
being chosen in situations where ISP strategies might produce signifi
cantly greater levels of safety at reasonable cost. To avoid this problem of
underestimation, PSAs need to more carefully consider human reliability,
commoncause errors and, in particular, organizational safety culture.
Another consequence of underestimating the failure probability of
a conventional system of active, passive, and procedural controls is
that such underestimates can lead to a neglect of offsite emergency
response and emergency preparedness because of the belief that they
are unnecessary. Consequently, plant personnel have insufficient famil
iarity with offsite agencies emergency plans and procedures to work
effectively with them when emergencies occur. This can lead to major
problems in the implementation of warning and protective actions (shelter
in place or evacuation) of nearby residents.
Finally, underestimating the failure probability of a conventional sys
tem of active, passive, and procedural controls hinders risk communica
tion with other stakeholders. In many cases, community groups focus
on the worstcase accident and have relatively little interest about the
estimated probability of that event. By contrast, plant personnel typically
focus on the (estimated) low probability of a worstcase accident and
believe that this justifies a low priority for what they consider to be only
marginally greater safety at significantly greater cost. The disagreements
are likely to be particularly acute if community groups mistrust plant
management and, thus, have low confidence in the effectiveness of a
conventional system of active, passive, and procedural controls.
OCR for page 59
78 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
REFERENCES
Adu, I. K., H. Sugiyama, U. Fischer, and K. Hungerbuhler. 2008. Comparison of methods for assess -
ing environmental, health and safety (EHS) hazards in early phases of chemical process design .
Process Saf. Environ. Protect. 86(3):77-93.
Al-Mutairi, E. M., J. A. Suardin, S. M. Mannan, and M. M. El-Halwagi. 2008. An optimization ap -
proach to the integration of inherently safer design and process scheduling. J. Loss Prevent.
Proc. Ind. 21(5):543-549.
Amyotte, P. R., A. U. Goraya, D. C. Hendershot, and F. I. Khan. 2006. Incorporation of inherent
safety principles in process safety management. Pp. 175-207 in 21st Annual Center for Chemical
Process Safety International Conference on Process Safety Challenges in a Global Economy.
New York: American Institute of Chemical Engineers.
Ashford, N. A. 1993. The Encouragement of Technological Change for Preventing Chemical Ac-
cidents: Moving Firms From Secondary Prevention and Mitigation to Primary Prevention.
Cambridge, MA: Center for Technology, Policy and Industrial Development, Massachusetts
Institute of Technology.
Berger, S. A., and R. J. Lantzy. 1996. “Reducing Inherent Risk Through Consequence Modeling.”1996
Process Plant Safety Symposium, ed. Hatice Cullingford, 15-23. Houston, TX: South Texas Sec-
tion of the American Institute of Chemical Engineers.
Atherton, J., and F. Gil. 2008. Incidents that Define Process Safety. Hoboken, NJ: Wiley.
Bollinger, R. E., D. G. Clark, R. M. Dowell, R. M. Ewbank, D. C. Henershot, W. K. Lutz, S. I.
Meszaros, D. E. Park, and E. D. Wixom. 1996. Inherently Safer Chemical Processes: A Life
Cycle Approach. New York: Center for Chemical Process Safety of American Institute of
Chemical Engineers.
Carvalho, A., R. Gani, and H. Matos. 2008. Design of sustainable chemical processes: System -
atic retrofit analysis generation and evaluation alternatives. Process Saf. Environ. Protect.
86(5):328-346.
CCPS (Center for Chemical Process Safety). 1998. Guidelines for Design Solutions for Process
Equipment Failures. Hoboken, NJ: Wiley.
CCPS. 2008. Guidelines for Hazard Evaluation Procedures, 3rd Ed. Hoboken, NJ: Wiley.
CCPS. 2009. Inherently Safer Chemical Processes: A Life Cycle Approach, 2nd Ed. Hoboken, NJ:
Wiley
CCPS. 2010. Final Report: Definition for Inherently Safer Technology in Production, Transportation,
Storage, and Use. Prepared by Center for Chemical Process Safety, The American Institute
of Chemical Engineers, for U.S. Department of Homeland Security, Science & Technology,
Chemical Security Analysis Center, Aberdeen Proving Ground, MD. July 19 [online]. Avail -
able: http://www.aiche.org/uploadedFiles/CCPS/Resources/KnowledgeBase/IST%20Final%20
Definition%20Report.pdf. Accessed Sept. 23, 2011.
Conta Costa Health Services. 1999. County Ordinance Chapter 450-8: Industrial Safety Ordi-
nance. Contra Costa County, California [online]. Available: http://cchealth.org/groups/hazmat/
industrial_safety_ordinance.php. Accessed: Sept. 23, 2011.
Cordella, M., A. Tugnoli, F. Barontini, G. Spadoni, and V. Cozzani. 2009. Inherent safety of sub- sub-
stances: Identification of accidental scenarios due to decomposition products. J. Loss Prevent.
Proc. Ind. 22(4):455-462.
Cozzani, V., F. Barontini, and S. Zanelli. 2006. Assessing the inherent safety of substances: precursors
of hazardous products in the loss of control of chemical systems. In 06 AIChe: Proceedings of
American Institute of Chemical Engineers Spring National Meeting, April 23-27, 2006, Orlando,
FL. New York: American Institute of Chemical Engineers.
DHS (U.S. Department of Homeland Security). 2010. Final Report: Definition For Inherently Safer
Technology in Production, Transportation, Storage, and Use. Prepared by CCPS for U.S. DHS.
July 2010.
OCR for page 59
79
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
Doran, P., and T. R. Greig. 1993. Mond Index: How to Identify, Assess and Minimise Potential Haz-
ards on Chemical Plant Units for New and Existing Processes, 2nd Ed. Northwich: Imperial
Chemical Industries.
Dow (Dow Chemical Company). 1994a. Dow’s Fire and Explosion Index Hazard Classification
Guide, 7th Ed. New York: American Institute of Chemical Engineers.
Dow. 1994b. Dow’s Chemical Exposure Index, 1st Ed. New York: American Institute of Chemical
Engineers.
Edwards, D. W. 2005. Are we too risk-averse for inherent safety? An examination of current status
and barriers to adoption. Process Saf. Environ. Protect. 83(2):90-100.
Edwards, D. W., and D. Lawrence. 1993. Assessing the inherent safety of chemical process routes.
Process Saf. Environ. Protect. 71(B4):252-258.
Edwards, D. W., A. G. Rushton, and D. Lawrence. 1996. Quantifying the Inherent Safety of Chemi -
cal Process Routes. Paper presented at the 5th World Congress of Chemical Engineering, July
14-18, 1996, San Diego, CA.
Englund, S. M. 1991. Design and operate plants for inherent safety—Part 2. Chem. Eng. Prog.
(May):79-86.
Englund S. M. 1991. Design and operate plants for inherent safety—Part 1. Chem. Eng. Prog.
(March):85-91.
Englund, S. M. 1993. “Process and Design Options for Inherently Safer Plants.” Prevention and
Control of Accidental Releases of Hazardous Gases, ed. Vasilis M. Fthenakis, 9-62. New York:
Van Nostrand Reinhold.
Englund, S. 2007. Safety condition in chemical process industries. Pp. 83-146 in Kent and Riegel’s
Handbook of Industrial Chemistry and Biotechnology, Vol. 1, ed. J. A. Kent. New York: Springer.
EPA (U.S. Environmental Protection Agency). 1987. Technical Guidance for Hazards Analysis: Emer-
gency Planning for Extremely Hazardous Substances. U.S. Environmental Protection Agency,
Federal Emergency Management Agency, U.S. Department of Transportation. December [on -
line]. Available: http://www.epa.gov/osweroe1/docs/chem/tech.pdf. Accessed: Oct. 4, 2011.
Etowa, C. B., P. R. Amyotte, M. J. Pegg, and F. I. Khan. 2002. Quantification of inherent safety
aspects of the Dow indices. J. Loss Prevent. Proc. Ind. 15(6):477-487.
French, R. W., D. D. Williams, and E. D. Wixom. “Inherent Safety, Health and Environmental (SHE)
Reviews.” Proceedings of the 29th Annual Loss Prevention Symposium, ed. Everett D. Wixom
and Robert P. Benedetti, Paper 1c. New York: American Institute of Chemical Engineers, 1995.
Gentile, M., W. J. Rogers, and M. S. Mannan. 2003. Development of a fuzzy logic-based inherent
safety index. Process Saf. Environ. Protect. 81(6):444-456.
Gertman, D., H. Blackman, J. Marble, J. Byers, and C. Smith. 2005. The SPAR-H Human Reliability
Analysis Method. NUREG/CR-6883. Idaho National Laboratory. Rockville, MD: U.S. Nuclear
Regulatory Commission [online]. Available: http://www.nrc.gov/reading-rm/doc-collections/
nuregs/contract/cr6883/cr6883.pdf. Accessed: Feb. 15, 2012.
Gowland, R. T. 1995. “Applying Inherently Safer Concepts to an Acquisition Which Handles
Phosgene.”Proceedings of the 29th Annual Loss Prevention Symposium, ed. Everett D. Wixom
and Robert P. Benedetti, Paper No. 1d. New York: American Institute of Chemical Engineers.
Gupta, J. P., and D. W. Edwards. 2003. A simple graphical method for measuring inherent safety. J.
Hazard. Mater. 104(1-3):15-30.
Hassim, M. H., and D. W. Edwards. 2006. Development of a methodology for assessing inherent
occupational health hazards. Process Saf. Environ. Protect. 84(5):378-390.
Hassim, M. H., and M. Hurme. 2010a. Inherent occupational health assessment during basic engineer-
ing stage. J. Loss Prevent. Proc. Ind. 23(2):260-268.
Hassim, M. H., and M. Hurme. 2010b. Inherent occupational health assessment during preliminary
design stage. J. Loss Prevent. Proc. Ind. 23(3):476-482.
Hassim, M. H., and M. Hurme. 2010c. Inherent occupational health assessment during process re -
search and development stage. J. Loss Prevent. Proc. Ind. 23(1):127-138.
OCR for page 59
80 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
Hassim, M. H., and M. Hurme. 2010d. Occupational chemical exposure and risk estimation in process
development and design. Process Saf. Environ. Protect. 88(4):225-235.
Hendershot, D.C. 2003. Inherently Safer Design. SACHE Faculty Workshop, September 2003, Baton
Rouge, LA [online]. Available: http://static.scribd.com/docs/io019xho1iqpt.txt. Accessed: Sept.
27, 2011.
Hendershot, D. C. 2006. An overview of inherently safer design. Process Saf. Prog. 25(2):98-107.
Hendershot, D. C. 2010a. A summary of inherently safer technology. Process Saf. Prog. 29(4):389-392.
Hendershot, D. C. 2010b. Inherently safer technology. J. Chem. Health Saf. 17(2):29-30.
Hendershot, D. C. 2011a. Defining inherently safer technology. J. Chem. Health Saf. 18(1):46-47.
Hendershot, D. C. 2011b. Inherently Safer Design: An Overview of Key Elements. All Business
com [online]. Available: http://www.allbusiness.com/safety-accidents-disasters/accidents-chem-
ical/15519792-1.html#ixzz1Y7Tswa3b. Accessed: Sept. 27, 2011.
Hendershot, D. C., and S. Berger. 2006. Inherently Safer Design and Chemical Plant Security and
Safety. Prepared for submission to the U.S. Senate Environment and Public Works Committee,
June 21, Washington, DC [online]. Available: http://epw.senate.gov/109th/Hendershot_Testi-
http://epw.senate.gov/109th/Hendershot_Testi-
mony.pdf. Accessed: Sept. 27, 2011.
Horng, J-J., Y-S. Lin, C-M. Shu, and E. Tsai. (2005). Using consequence analysis on some chlorine
operation hazards and their possible effects on neighborhoods in central Taiwan. J. Loss Prevent.
Proc. Ind. 18:474-480.
Hurme, M., and M. Rahman. 2005. Implementing inherent safety throughout process lifecycle. J. Loss
Prevent. Proc. Ind. 18(4-6):238-244.
Khan, F. I., and P. R. Amyotte. 2003. How to make inherent safety practice a reality. Can. J. Chem.
Eng. 81(1):2-16.
Khan, F. I., and P. R. Amyotte. 2004. Integrated inherent safety index (I2SI): A tool for inherent safety
evaluation. Process Saf. Prog. 23(2):136-148.
Khan, F. I., and P. R. Amyotte. 2005. I2SI: A comprehensive quantitative tool for inherent safety and
cost evaluation. J. Loss Prevent. Proc. Ind. 18(4-6):310-326.
Khan, F. I., R. Sadiq, and P. R. Amyotte. 2003. Evaluation of available indices for inherently safer
design options. Process Saf. Prog. 22(2):83-97.
Kletz, T. A. 1978. “What you don’t have, can’t leak.” Chem. Ind. (May 6):287-292.
Kletz, T. A. 1984. Cheaper, Safer Plants, or Wealth and Safety at Work: Notes on Inherently Safer and
Simpler Plants. Rugby, Warwickshire, UK: The Institution of Chemical Engineers.
Kletz, T. A. 1985. Inherently safer plants. Plant/Operations Progress. 4(3):164-167.
Kletz, T. A. 1991. Plant Design for Safety: A User-Friendly Approach. New York: Hemisphere Pub.
Kletz, T. A. 1996. Inherently safer design: The growth of an idea. Process Saf. Prog. 15(1):5-8.
Kletz, T. A. 1998. Process Plants: A Handbook for Inherently Safer Design. Philadelphia: Taylor &
Francis.
Kletz, T. A., and P. Amyotte. 2010. Process Plants: A Handbook for Inherently Safer Design, 2nd Ed.
Boca Raton, FL: CRC Press.
Kossoy, A., A. Benin, and Yu. Akhmetshin. 2007. Simulation-based approach to design of inherently
safer processes. In Loss Prevention 2007: 12th International Symposium on Loss Prevention
and Safety Promotion in the Process Industries. Rugby, UK: IChemE.
Landucci, G., A. Tugnoli, C. Nicolella, and V. Cozzani. 2007. Assessment of inherently safer technol-
technol-
ogies for hydrogen storage. Pp. 1191-1196 in Loss Prevention 2007: 12th International Sympo-
sium on Loss Prevention and Safety Promotion in the Process Industries. Rugby, UK: IChemE.
Landucci, G., A. Tugnoli, and V. Cozzani. 2008. Inherent safety key performance indicators for hy- hy-
drogen storage systems. J. Hazard. Mater. 159(2-3):554-566.
Landucci, G., A. Tugnoli, C. Nicolella, and V. Cozzani. 2007. Assessment of inherently safer technol-
technol-
ogies for hydrogen storage. Pp. 1191-1196 in Loss Prevention 2007: 12th International Sympo-
sium on Loss Prevention and Safety Promotion in the Process Industries. Rugby, UK: IChemE.
OCR for page 59
81
THE CONCEPTS OF INHERENTLY SAFER PROCESSES AND ASSESSMENT
Leong, C. T., and A. M. Shariff. 2008. Inherent safety index module (ISIM) to assess inherent safety
level during preliminary design stage. Process Saf. Environ. Protect. 86(2):113-119.
Leong, C. T., and A. M. Shariff. 2009. Process route index (PRI) to assess level of explosiveness for
inherent safety quantification. J. Loss Prevent. Proc. Ind. 22(2):216-221.
Lin, D., A. Mittelman, V. Halpin, and D. Cannon. 1994. Inherently Safer Chemistry: A Guide to Cur-
rent Industrial Processes to Address High Risk Chemicals. Washington, DC: Office of Pollution
Prevention and Toxics, U.S. Environmental Protection Agency.
Lindell, M. K., and Perry, R. W. (2006). Onsite and offsite emergency preparedness. Pp. 1959-1971
in S. Lee. (Ed.) Encyclopedia of Chemical Processing. New York: Marcel Dekker.
Mannan, S., ed. 2005. Lee’s Loss Prevention in the Process Industries, 3rd Ed. Oxford, UK: Elsevier
Butterworth-Heinemann.
Mansfield, D. P., R. D. Turney, R. L. Rogers, M. Verwoerd, and P. Bots. “How to Integrate Inherent
SHE in Process Development and Plant Design.”IChemE Conference, Major Hazards Onshore
and Offshore 1995.
Manuele. F. A. 2003 On the Practice of Safety. Hoboken, NJ: John Wiley & Sons.
Meel, A., and W. D. Seider. 2005. Dynamic risk assessment of inherently safe chemical processes: Ac-
cident precursor approach. In 2005 Spring National Meeting Conference Proceedings, Atlanta,
GA. New York: American Institute of Chemical Engineers.
Mulhern, B. 2008. Up on green roofs. Turf Magazine, January [online]. Available: http://www.turf
magazine.com/article-192.aspx. Accessed Sept. 27, 2011.
NJ DEP (New Jersey Department of Environmental Protection). 2009. News about the TCPA Pro -
gram: Toxic Catastrophe Prevention Act (TCPA) TCPA 13:1K-24, March 16 [online]. Available:
http://www.state.nj.us/dep/rpp/brp/tcpa/tcpanews.htm. Accessed: Sept. 23, 2011.
Palaniappan, C., R. Srinivasan, and I. Halim. 2002a. A material-centric methodology for develop -
ing inherently safer environmentally benign processes. Comput. Chem. Eng. 26(4-5):757-774.
Palaniappan, C., R. Srinivasan, and R. Tan. 2002b. Expert system for the design of inherently safer
processes. 1. Route selection stage. Ind. Eng. Chem. Res. 41(26):6698-6710.
Palaniappan, C., R. Srinivasan, and R. Tan. 2002c. Expert system for the design of inherently safer
processes. 2. Flowsheet development stage. Ind. Eng. Chem. Res. 41(26):6711-6722.
Puranik, S. A., K. K. Hathi, and R. Sengupta. “Prevention of Hazards Through Technological
Alternatives.”Safety and Loss Prevention in the Chemical and Oil Processing Industries, 581-
87. IChemE Symposium Series, no. 120. Rugby, Warwickshire, UK: The Institution of Chemical
Engineers, 1990.
Rahman, M., A. M. Heikkila, and M. Hurme. 2005. Comparison of inherent safety indices in process
concept evaluation. J. Loss Prevent. Proc. Ind. 18(4-6):327-334.
Rogers, R. L., and S. Hallam. 1991. “A Chemical Approach to Inherent Safety.” IChemE Symposium
Series No. 124:235-241.
Rogers, R. L., D. P. Mansfield, Y. Malmen, R. D. Turney, and M. Verwoerd. 1995. The INSIDE
project: Integrating inherent safety in chemical process development and plant design. In Inter-
national Symposium on Runaway Reactions and Pressure Relief Design, ed. G. A. Melhem and
Harold G. Fisher, 668-89. New York: American Institute of Chemical Engineers.
Rusli, R., and A. M. Shariff. 2010. Qualitative assessment for inherently safer design (QAISP) at
preliminary design stage. J. Loss Prevent. Proc. Ind. 23(1):157-165.
Scheffler, N. E. 1995. Inherently safer latex plants. In Proceedings of the 29th Annual Loss Preven-
tion Symposium, ed. Everett D. Wixom and Robert P. Benedetti, Paper 1b. New York: American
Institute of Chemical Engineers.
Shah, S., U. Fischer, and K. Hungerbuhler. 2003. A hierarchical approach for the evaluation of
chemical process aspects from the perspective of inherent safety. Process Saf. Environ. Protect.
81(6):430-443.
Shariff, A. M., and C. T. Leong. 2009. Inherent risk assessment—A new concept to evaluate risk in
preliminary design stage. Process Saf. Environ. Protect. 87(6):371-376.
OCR for page 59
82 USE AND STORAGE OF METHYL ISOCYANATE (MIC) AT BAYER CROPSCIENCE
Shariff, A. M., and D. Zaini. 2010. Toxic release consequence analysis tool (TORCAT) for inherently
safer design plant. J. Hazard. Mater. 182(1-3):394-402.
Shariff, A. M., R. Rusli, C. T. Leong, V. R. Radhakrishnan, and A. Buang. 2006. Inherent safety tool
for explosion consequences study. J. Loss Prevent. Proc. Ind. 19(5):409-418.
Sorensen, J. H., Shumpert, B. L. and. Vogt, B. M. (2004). Planning for protective action decision
making: evacuate or shelter-in-place. J. Hazard. Mater. A109, 1-11.
Spurgin, A. J. (2010). Human Reliability Assessment: Theory and Practice. Boca Raton: CRC Press.
Srinivasan, R., and A. Kraslawski. 2006. Application of the TRIZ creativity enhancement approach to
design of inherently safer chemical processes. Chem. Eng. Process. 45(6):507-514.
Srinivasan, R., and N. T. Nhan. 2008. A statistical approach for evaluating inherent benign-ness of
chemical process routes in early design stages. Process Saf. Environ. Protect. 86(3):163-174.
Swain, A. D., and H. E., Guttmann. 1983. Handbook on Human Reliability Analysis with Emphasis
on Nuclear Power Plant Application. NUREG/CR-1278. SAND 80-0200 RX, AN. Final Report.
Rockville, MD: U.S. Nuclear Regulatory Commission.
Tugnoli, A., G. Landucci, and V. Cozzani. 2009. Key performance indicators for inherent safety: Ap-
Ap-
plication to the hydrogen supply chain. Process Saf. Prog. 28(2):156-170.
U.S. Department of Labor. Occupational Health and Safety Administration. Process safety man -
agement of highly hazardous chemical. (29 CFR § 1910.119) [online]. Available at http://
www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9760. Ac-
cessed: April 6, 2011.
Van Willigen, M., T. Edwards, B. Edwards, and S. Hessee. 2002. Riding out the storm: The experi -
ences of the physically disabled during Hurricanes Bonnie, Dennis, and Floyd. Natural Hazards
Review 3(3):98-106.
Windhorst, J. C. A. 1995. Application of inherently safe design concepts, fitness for use and risk
driven design process safety standards to an LPG project. In Loss Prevention and Safety Pro-
motion in the Process Industries, ed. J. J. Mewis, Hans J. Pasman, and E. E. De Rademacker,
543-54. Amsterdam: Elsevier Science B. V.