The growth of the chemical industry has resulted in the usage of more hazardous materials, typically at high pressures and temperatures. This increases a specific operation’s risk factors. Safety, risk evaluation, and hazard control now have the highest priority.

The chemical sector is an important element of industrial activities, which is progressing steadily. Specialty chemicals have high risks and hazards throughout manufacture, becoming essential to different industrial operations and product manufacturing. These dangers and risks are linked to equipment like furnaces, boilers, and cracking units that nearly invariably operate at extremely high pressures and temperatures. The potential effects on human life and the environment make these hazards much more significant.

These and other variables make it essential for manufacturers to take safety, hazard, and risk assessment seriously to recognize, comprehend, and develop strategies to reduce the hazards associated with a chemical plant.

This comprehensive article is a guide and not the ultimate declaration on each method, but it provides enough details for operators and engineers working in the process or chemical industries to make a well-informed choice about which approach might be most appropriate in a given situation and to evaluate the thoroughness and caliber of hazard and safety management. It is the obligation of each potential user to gain training and assistance from a professional before adopting any specific approach.

Let’s make a brief understanding of the important terms related to this topic:

What is Hazard?

A hazard is any specific situation, external or internal to the system, that can result in a disaster involving property, life, and environmental harm [1]. The origin of risk is identified by hazard [2].

What is Risk?

Risk is a way of describing the likelihood that a hazard will occur. It differs from a hazard in that risk indicates the probability of a hazard. Conversely, hazard identifies the source of risk [2]. Three main questions are resolved in risk analysis: (1) what is possible? (2) how often will it occur? (3) the implications.

Hazard Management

Hazard management is a comprehensive technique for describing issues and identifying hazards, collecting information about those hazards and assessing the risks, and then resolving, managing, and mitigating those risks.

Safety Management

Safety management is a set of well-organized, corporate or plant-wide procedures that provide efficient risk-based decision-making for routine industrial tasks. Safety systems assist businesses in providing the safest possible products and ensuring secure operations.

1 Hazard Identification

In a process plant or any other facility in the chemical industry, hazard identification is essential to the secure design and operation of any system. Depending on the circumstance, different methods are utilized, but they are all rigorous and systematic and rely on a lesser or greater extent of knowledge, typically including some level of experience. The following list includes some of the most popular techniques:

  • Fault Tree Analysis
  • Event Tree Analysis
  • Failure Modes Effects Analysis

Hazard identification tools are employed at the appropriate time throughout the development of a certain project. There may be numerous stages in a project where a method may be employed profitably; therefore, the timing of adoption is not necessarily crucial.

It should be understood that a “project” might be a maintenance operation, a modification, or a sizable development project for a process plant. Any of them can be recognized using identification techniques; the only variations are in the effort, complexity, and documentation. Although they originated in the process industry, certain techniques are more applicable there. The necessity and the intended study outcome should always be considered while choosing the techniques.

The term “Hazard Identification Methods” has been widely used. The two oldest are most likely “Checklists” and “What If?” The earliest method, Hazard and Operability Studies (formerly known as HAZOP) was tested in 1968. Since then, new techniques have emerged, some of which are modifications of earlier techniques.

It is difficult to develop an equally effective method for all operations involved in the process industry to identify hazards.

The following is a general hierarchy of risk-reducing measures:

  • Prevention
  • Detection
  • Control
  • Mitigation
  • Emergency response

These techniques can be applied analytically as well as quantitatively.

When conducting a study, there are specific regulations that must be followed. The Scope defines the limits of the research and specifies what will and will not be included in the investigation. It has to address who is responsible for carrying them out and whether or not they should be prioritized. After a HAZOP, when there may have been significant modifications to the drawings, the Scope should include clarifying who is responsible for doing a restudy.

2 Hazard Analysis

Hazard analysis, also called Hazard Studies, according to the primary intention of ICI, has various additional identities. Project hazard studies, process safety reviews, preliminary hazard analyses, project SHE reviews, etc., are examples of common ones.

It is a systematic study of a process and control project performed by chosen teams of qualified professionals at specified stages during its development to verify that the safety requirements incorporated into the project are met.

The most typical set of studies, conducted as necessary throughout the project’s life cycle, are:

(1) Conceptual design

(2) Design process

(3) Detailed engineering design

(4) Verification of construction design

(5) Pre-commissioning safety analysis

(6) Post start-up

The numbers are the same as those mentioned in the conventional Safety Studies which ICI developed in the 1970s.

As the project progresses and the detail gets more obvious, the team makeup and documentation vary from study to study. It has been standard practice to include two more studies in recent years.

(0) Inherently safer/less harmful design

(7) Demolition and decommissioning

It is crucial to understand that these studies are interlinked and, to some extent, feed into other studies. Each one looks at the prior research findings and will inform the one after that. The timeline is crucial to ensure that each evaluation is carried out at the right time during the project and avoids being done either too early, when the definition may still be lacking, or too late, when there may be few possibilities for modification.

2.1 Study 0: Inherent Safe Design

This study aims to analyze and put into practice the concepts of inherently safe design. On the team will be a person in charge of the project, a chemical engineer, a chemist, a safety engineer, and a technology expert.

The ideal scenario would have been a thorough examination of the background of that kind of procedure, including a check of accident records.

Guidewords are used to begin the inherently safer procedure and some of them are:

  • Intensify
  • Attenuate
  • Change
  • Substitute
  • Eliminate

Intensify: Minimize the working inventory or overall leak potential by concentrating the process in a more compact reactor with higher pressure. An example is a high-pressure catalytic reactor, which is substantially smaller than a traditional low-pressure reactor. Another option is switching from a constantly stirred-back mixed reactor to a linear reactor.

Attenuate: Lower the operating temperature or pressure such that the leak rate has a reduced likelihood of igniting or exploding. An example would be chilled storage for cryogenics rather than “green-field” storage.

Get it right the first time: Eliminate the need for changes at the last minute or even learn about the conditions that may affect the overall process.

Substitute: Change the production route to use chemicals that are safer or do not create hazardous intermediates or by-products. Steam is intrinsically safer than hot oil. Because steam heating has a high, self-limiting temperature, it could be safer than electrical heating.

Eliminate: When choosing the design pressures for your equipment, can you avoid the necessity for overpressure protection? The capacity to recover from and endure an upset or tolerate the extremes of the operating/upset conditions envelope are additional factors to consider. Also, consider the environment while figuring out how to catch leaks and rework them.

2.2 Study 1: Concept Stage Hazard Review

The fundamental Safety, Health, and Environment (SHE) information for the operation is evaluated in this investigation. This research should determine what additional information is needed and specify the schedule of studies necessary to ensure that all safety, health, and environmental problems can be effectively handled during the project. A basic problem should be investigated to see if it effect project progress. Typical problems include:

  • The feedstock qualities, the product and by-products, toxicity, and handling
  • Operative/start-up circumstances
  • Reactor control and reaction kinetics
  • Heating (cooling) systems that are intrinsically safer
  • Containment reliability
  • Effect on the environment
  • Usefulness and appropriateness of the site
  • The source of the materials and any transportation concerns
  • Building construction

Furthermore, any restrictions imposed by relevant law should be addressed.

2.3 Study 2: Process Design

The design alternative is being developed at the time of this research, and thorough design is only getting started. In order to manage these risks, it will often address risk assessment, hazard identification, and the operability and control elements that must be included in the detailed design. The analysis should look for any remaining problems that may cause the project’s design to be delayed.

Typical problems include:

  • Developing project safety criteria
  • Performing the start-up/shutdown evaluation
  • Examining the reactor’s output of harmful by-products
  • Performing the over/under pressure analysis
  • Performing a preliminary evaluation of the shutdown system’s performance
  • Considering both the safety impact of existing systems on the new system and the impact of the new system on existing systems
  • Taking into account the location of inhabited buildings both on and off-site
  • Taking into account any unique environmental elements
  • Regulatory clearances

The research team will study 0 and 1 stages and include operational staff and experts as needed. The initial Risk Assessments will be performed at this stage, especially if necessary for developing a Safety Case.

2.4 Study 3: Detailed Engineering Design

This analysis thoroughly examines a design to determine any flaws and discover hazards and operability issues. At this point, HAZOP experiments are often conducted [3]. Typical features include:

  • Verification that the design meets the project requirements
  • Looking at isolation requirements for removing equipment for repair
  • Examining the prerequisites for preparing to remove equipment for maintenance
  • Research on how to handle materials, such as how to access and remove equipment for repair
  • Research on evacuation
  • Research on relief and blowdown
  • Hazard area designation

The team might comprise mechanical, instrumentation, and electrical experts in addition to participants from study 2. Since different requests will arise at various points during the design process, the timeframe is challenging to estimate.

2.5 Study 4: Construction/Design Verification

In the last stages of construction, this evaluation is carried out. The hardware is examined to ensure that it has been constructed according to the designer’s specifications and that there have been no variances. It is also validated that operational and emergency procedures are examined and the steps from hazard study number 3 have been implemented. Typical features include:

  • As-built plans
  • Reservation and punch lists
  • Start-up and commissioning processes
  • Team building and training

2.6 Study 5: Pre-commissioning Safety Review

This examination conducted immediately before commissioning, determines if all construction-related concerns have been resolved and whether the commissioning team is prepared to begin operations. It may be considered a type of audit. Typical issues include:

  • Operational regulations
  • Getting ready before starting (equipment testing, cleaning, purging, drying, system shutdown function testing)
  • Operator education and training
  • Adherence to corporate and legislative norms
  • Examining the management of change processes, including examinations of earlier-staged changes

This study can be conducted like study 4 and be of comparable duration. SHE experts from the company might be a part of the team. There is just one more chance to fix any software and hardware issues.

2.7 Study 6: Post Start-up Review

This survey is conducted 6-12 months following the company’s inception. The project manager, plant manager and engineer, commissioning manager, and any other needed professionals should be on the team. The duration should not exceed a few days. This study must be applied to enhance upcoming projects and design systems.

2.8 Study 7: Demolition and Decommissioning

Many of the elements of studies 1 and 2 are present in this investigation. It looks for any problems that can arise during the decommissioning and destruction processes. The team should have members with knowledge of demolition as well as the design and execution of the process. The intricacy and scale of the plant will determine how long the investigation will go, although it might go on for many days. Typical problems could be:

  • Potential leftover fluids, associated dangers, and disposal or re-use techniques.
  • The elimination and re-use of catalysts.
  • Prepare the facility for destruction.
  • Make the most of recycled materials like high-alloy or stainless steel power cables.
  • Dangers related to “waste materials” (asbestos, catalysts, and things lodged in drains).

3 Hazard Identification and Management Techniques

This section will cover a comprehensive review of hazard identification and management techniques that might be used in different operations or scenarios in the process industry.

3.1 Hazard and Operability Study (HAZOP)

A HAZOP study is a multidisciplinary team’s organized examination of a system functioning. The team examines a concrete design for the operation or the procedure line-by-line or stage-by-stage. This is accomplished by looking for a deviation from the original design intention using a set of guidewords in conjunction with the system parameters. When a possible danger or operability issue is identified, the team uses their collective knowledge to determine whether the modification or more research is required. It is one of the most extensively utilized methods of hazard detection in process (and many other) industries.

This research should only be carried out once a well-defined and frozen state for the process description and the entire design is available. Any further adjustments must only be those required by the HAZOP study’s inferences or carried out under stringent management of change procedures. The Scope of the study, including the equipment to be inspected and the required methods of operation, must be established. The Scope should also include the possible issues that should be looked for. The procedure or operation is broken down into sections or phases, each of which the team reviews.

Figure 1: A flowchart describing the HAZOP analysis of a particular step or element of an operation.

Advantages

  • The technique can identify risks as well as operational issues.
  • An organized approach increases the likelihood of spotting potential problems.
  • Various risks can be evaluated, including those posed by chemicals, machinery, electricity, controls, and human contact.
  • Investigate unique and new processes.
  • The team acquires a thorough grasp of how the procedure will probably function.
  • A quicker start-up, fewer operational issues, and more dependability may have a financial payoff.

Disadvantages

  • The need for a multidisciplinary team and an experienced manager.
  • The high resource needs, both in terms of labor and data.
  • The necessity to complete the research within a constrained time frame and project life.

3.2 Task Analysis

A task is analyzed in an organized way using the Task Analysis technique. The process is broken down into specific phases to investigate each stage in the sequence and determine what can go wrong and what could be done to prevent or lessen the outcome.

Each stage of the chosen procedure is examined using task analysis. This could be a process-related, upkeep-related, or inspection-related duty. The task is initially examined to determine the necessary flow of events, such as what the operator must perform and what hardware modifications must be done or will be made to get the desired outcome. The analyst then thinks about each step and determines what may go wrong with it, if it could be skipped or performed in the incorrect sequence, and how any potential issues could be fixed. The operations team, which will prepare and transport the equipment, will be contacted in instances of maintenance and inspection. It is frequently used to analyze operating procedures and is typically applied to safety-critical phases in a process.

Advantages

  • It takes advantage of the expertise of those who have performed the assignment before.
  • It is adapted to each task’s specific needs.
  • It could employ a simple Hazard Study format.

Disadvantages

  • It could be based on experience that does not apply to the task at hand, or the experienced individual might not be easy to find.
  • When looking at simpler (inherently safer) procedures, there is a temptation to depend only on expertise and lose any structure in the analysis.

3.3 Failure Modes and Effects Analysis

A Failure Modes and Effects Analysis (FMEA) methodically examines all potential single failure modes of the various plant components and system elements. Each failure’s impact on the individual item and the rest of the system is recorded. Typically, a small team with an in-depth understanding of the machinery does the analysis. The seriousness of the effects and their propensity to occur are also evaluated and noted in an FMEA.

FMEA is a rigorous yet time-consuming technique for identifying hazards. It looks at every possible mode of failure for each component and portion of a chosen system, often a hardware component. The effects of each failure mode must be identified to establish if the reaction to this failure was adequate. It is an established technique with substantial guidelines [4,5].

The steps in the analysis process are first to determine the Scope of the research, then choose the level of analysis, and finally gather the required documentation. The physical limits of the hardware component are typically the designated physical boundary. A thorough description of the system, its operation, and its context are necessary, much like in a HAZOP analysis.

In order to thoroughly assess the impact of failures, key documentation elements will comprise the equipment designs, manuals, and data on protective measures. A thorough investigation will also need to look into potential service breakdowns (steam, electrical, cooling water, instrument air, etc.). To cover these appropriately, the team members must be familiar with the system, especially its operating history and failure mechanisms. The system is then rationally and methodically worked through by a small team, generally the manager and individuals with vast technical expertise, for instance, working downstream item to item. An engineer having information about the system’s design and functioning would be an excellent team.

Advantages

  • It is useful for identifying dangers linked to mechanical and electrical equipment failures, such as dependability issues.
  • The application is simple with obvious outcomes.
  • The study can identify regional and global system flaws.
  • A HAZOP analysis of a P&ID is analogous to an FMEA on an engineering item.
  • The team member needed is lower than for a HAZOP study.
  • It is possible to establish a semi-quantitative ranking of the risks.

Disadvantages

  • The approach is not the most successful at recognizing combinations of failures or when the danger arises from the overall process, although a skilled team may be assumed to detect it.
  • The approach focuses on the apparatus but ignores operational mistakes.
  • The analyst(s) must know how the equipment operates and failure mechanisms and determine how such failures affect other system components.
  • When used by an individual analyst, the approach can overlook significant interactions.

3.4 Fault Tree Analysis

Fault tree analysis (FTA) is an approach that concentrates on a certain undesirable event or primary system failure (the top event) and attempts to uncover all possible causes. The fault tree visually illustrates different equipment failures and human error combinations that might result in the top event. It may be used to determine the underlying reasons for risk and it can also be used to determine how often or frequently the top event may happen. It may help determine the underlying reasons for a large risk already identified and would only manifest itself in highly complicated circumstances.

The fault tree is typically built vertically, with the ultimate result at the top. The fault tree provides a visual representation of the structure of these circumstances as well as an estimated frequency for the top event through quantification using frequencies and likelihood. The tree can be built either “bottom-up” or “top-down,” starting with the causes and moving up to the top event. The top event in a full fault tree is connected to the beginning events through several intermediary levels where the prerequisites for the top event’s propagation are merged in AND or OR gates [6,7]. There will be many levels in a huge tree, and as the analysis moves away from the top event, the levels get more complicated and detailed. A basic fault tree for the occurrence of a fire in a processing facility would begin with the definition of the top event, followed by the identification of the necessary variables and a study of how these could occur. Figure 2 illustrates this type of fault tree.

Figure 2: A simple example of a fault tree for a process plant fire occurrence

Advantages

  • Fault tree analysis is a logical method to find combinations of human, equipment, and system faults that might pose a risk.
  • It is a deliberate, organized approach that results in a logical, pictorial representation of the underlying reasons for a danger.
  • The fault tree may be utilized to pinpoint important or single-point dependencies that contribute to the risk using the minimal cut set approach.
  • The fault tree helps identify the most important factors contributing to danger, especially if the outcome is numerical.
  • Using the method could inspire the analyst to look into unusual or new factors that could result in an unanticipated threat.

Disadvantages

  • Since fault trees are time-consuming to develop, they should only be utilized when necessary.
  • The analyst must be adept at using fault trees, particularly when deciding how much detail to add and possess a thorough knowledge of the system being studied.
  • If the access data are of low quality and lack robustness or relevance, the usefulness of a study will be constrained. It is not a method for making an exact forecast based on inaccurate data.

3.5 Layer of Protection Analysis

The layer of Protection Analysis (LOPA) is a methodical technique that examines a process plant’s safeguards to determine whether the level of protection offered is sufficient for each identified danger. With and without these extra aspects, the risk is compared against established risk criteria to determine if further controls or shutdown mechanisms are necessary. Although LOPA was initially intended to be an order-of-magnitude methodology, it has evolved by considering variables like failure probabilities and frequencies on demand that have been measured or calculated using tried-and-true techniques. This is especially important for human variables, which commonly start risks are considered when evaluating alarm systems as an additional layer of safety.

In order to assess the effectiveness of independent protection systems in chemical plants, LOPA looks at how they respond when an undesirable event occurs [8,9].

Figure 3: LOPA layers general view

Advantages

  • LOPA can be used as a rapid screening tool to determine whether a simple or more complicated shutdown mechanism is necessary (or not).
  • It offers a neatly organized tabulation, justifies the integrity level selection, and lists all the mitigating circumstances.
  • It clarifies the specifications for the development, use, and upkeep of safety systems.
  • Although the approach does not focus on identifying hazards in particular, it may be used to supplement those found during the HAZOP research stage and elaborate on their sources and effects.

Disadvantages

  • Quantifying the integrity of the independent protective layers and shutdown must justify systems.
  • The benefits of a protective layer may be subjectively evaluated and quantified.
  • LOPA may lessen the analytical precision.

3.6 The Risk Analysis Screening Tool (RAST)

RAST is a collection of process risk and safety analysis screening tools to support assessment teams. It fosters uniformity among analysis teams and strengthens company procedures and criteria. It uses streamlined, frequent empirical approaches to assess risks, repercussions, and dangers. The RAST technique facilitates to input chemicals, reactivity information, equipment type, operational parameters (such as pressures and temperatures), and facility layout. Then, depending on its internal database, Checklists, and what-If? RAST leverages these inputs to generate a preliminary list of risk scenarios before estimating the “worst” outcomes. Additional research teams may choose particular situations for a LOPA using the RAST program after the Hazard Evaluation is finished.

Figure 4: Hazard identification and risk analysis workflow

The timing of the research is extremely important since there might be serious financial repercussions if problems are found on a new project after it has been approved. To provide fundamental information, RAST is based on a proposed hazard identification and risk analysis work procedure (Figure 4). RAST begins with small data and gradually adds more to enhance the analysis.

RAST, in particular, is not a stand-alone application and should not be used by one person to make any risk-based choices. It does not answer all the problems arising during a complete risk evaluation.

Advantages

  • RAST can be used early on in a project, even if there are no precise P&IDs available. However, it necessitates some understanding of the final plan and equipment placement, which might not be accessible right once.
  • RAST offers a solid foundation for the team to build upon when developing risk scenarios, allowing them to include any known occurrences relevant to the equipment under examination.
  • The RAST software may be upgraded to represent the unique corporate process risk needs and criteria.
  • RAST helps the study team identify situations with low risk when a qualitative assessment of safety measures may be suitable.
  • RAST conducts a thorough consequence analysis to find high-risk situations that could prefer a more in-depth examination, like LOPA.
  • RAST contains the Relative Risk Ranking approach in addition to other methods to help the research team prioritize the work needed to create, put into place, and maintain the layers of protection for risk management.

Disadvantages

  • Although few things are needed in inputs to produce a qualitative risk assessment, substantial input data is necessary for semi-quantitative risk assessments like the LOPA.
  • To use the specialized capabilities of the RAST program, particularly when identifying if unsuitable inputs have been utilized and interpreting the findings, a thorough grasp of process risks and risk analysis approaches is essential.
  • In order to properly utilize RAST throughout the review, a cross-functional research team is needed.
  • The study team must identify additional Initiating Events (or Causes) for some of the danger scenarios listed in RAST as well as scenarios for less typical types of activities. However, an experienced team will find this a good place to start when “brainstorming.”

3.7 Checklists

A checklist is a carefully developed, detailed list of safety precautions, operating procedures, material characteristics, risks, or “good practice” design elements created by knowledgeable individuals for a specific application. Checklists are used to ensure that designs, operations, system status, etc., adhere to established regulations, standards, or other specified criteria.

The following sources might contribute to this list:

  • Global experience
  • Task analysis
  • HAZOP

Advantages

  • Checklists can be modified to meet the needs of specific applications and businesses.
  • Their usage is simple, organized, simple to comprehend, and can guarantee consistency.
  • They are especially helpful for routine or repetitive processes to ensure no obvious issue is ignored.
  • If analysts are urged to contribute to the list and have an open mind when using them, their worth will be increased.
  • They can help find and eliminate issues before they get embedded in the design’s details, saving time and money.

Disadvantages

  • It takes significant expertise and experience to develop an effective checklist.
  • Production and validation might need a lot of resources.
  • A fault can be overlooked if the checklist is incomplete due to inexperience.
  • The method may result in “blinkered” research that does not thoroughly examine the procedure’s risks.
  • Relying only on checklists might give a false perception of process safety.
  • New and unique processes are less suited to this technique.

3.8 What If?

It is a brainstorming method where a group of knowledgeable individuals with expertise in the research process pose questions and express their concerns about potential risks. The approach has a wide range and might be unstructured; however, the facilitator may provide some advice based on an initial examination of the process under study. More structure may be added by developing and implementing a checklist of inquiries and areas of concern. It is one of the earliest techniques for identifying hazards.

What-If is relatively easy to use and has applications at almost every step of a process’ existence. A small, professional team from many disciplines is responsible for carrying out the study. Using layout drawings, P&IDs, and other material and process papers, the research focuses on a specific step in the process and works through it while posing a series of What-If questions. Following the process stream or batch sequence, the team need to move systematically.

When analyzing a transfer line, one could think about issues like:

  • What if this line is not flowing? What may trigger it, and what results might it have?
  • What if maintenance calls for access? Can one access the equipment?
  • What if a fire breaks out? Can the emergency services gain entry? What facilities are present nearby?
  • What happens if a user is hurt? Is it possible to be rescued?
  • What happens if a strange condition develops?

The team will evaluate the effects in each instance and, considering the possible causes, assign a criticality grade to the event using a straightforward consequence-frequency matrix. When applicable, the team should list the alternatives or offer suggestions for improvement. The study results are provided in a straightforward table with columns for each What-If question’s consequences, safeguards, criticality, and recommendations. The approach will yield higher level and less risk-focused questions if used early in the process development, such as in the conception phase.

Advantages

  • The approach is extremely adaptable and may be applied at any stage of the life cycle of a process by altering the list of topics to be covered.
  • Since the method is straightforward, studies may be completed quite rapidly.
  • The method encourages the group to apply their creativity and knowledge.
  • What-If research can employ a different set of abilities and analyze less process-oriented hazards than a HAZOP study.
  • What-If may be incredibly helpful in the early phases of a project to pinpoint important difficulties and areas that require more research.
  • Well-designed research can determine new issues.

Disadvantages

  • The effectiveness of the approach is strongly influenced by the analyzer’s abilities, the origin of the discussion issues, and their depth of understanding.
  • The team can waste time on unimportant details or overlook crucial ones if the study is poorly organized.
  • Compared to other procedures, the outcomes are qualitative and less precise.
  • The leader must first undertake some preliminary research to determine the topics and questions to launch the debate and optimize its coverage.
  • It is challenging to evaluate the study’s quality.
  • The research used by an individual may provide a false sense of safety.

4 Current Trends

Risk assessment requires knowledge mining. This is a very difficult undertaking due to the complexity of the processes and systems involved, and as a result, experimenting may not always be physically possible or even practical from an economic standpoint [10]. This section will summarise several newly established hazard identification and risk assessment techniques [11].

SimHAZAN, a new hazard analysis method, uses simulation data and multi-agent modeling [12]. A computer-based hazard evaluation technique based on domain ontology, the scenario object model (SOM), may be utilized to describe the frameworks of the hazard identification process [13].

Numerous fields use quantitative risk assessment approaches. The static nature of these assessments, which prevents updating risk based on changing conditions, is one of the main drawbacks. As a result, the need for a dynamic risk assessment (DRA) technique was identified, and several attempts have been made to develop one that would enable real-time computation of risk indices. This decision would be made based on the information gathered while the particular system was operating. This makes it possible to estimate the system’s risk more precisely and reasonably.

Support vector machines and particle swarm optimization theory have been used with acoustic waves to predict the site of pipeline breaches, which can have damaging consequences [14]. These techniques are important for monitoring the process dynamically.

In the DRA approach, the estimated risk of a degrading process gets updated based on how well the control system, safety barriers, inspection and maintenance tasks, human factors, and the application of procedures are performing [15]. When using condition-monitoring data for DRA, it is necessary to continuously check the system’s operational state and deterioration processes [16]. The degradation processes themselves can be monitored to foretell failures by considering certain thresholds of the variables that will be monitored. This data is more useful than statistical failure data since it updates the dependability values before the real failures occur.

It can be difficult to monitor workplace safety in a large facility. Manual monitoring of hazardous conditions is not the best option, not even in a small workplace like an office. Innovations in the Industrial Internet of Things (IIoT) have developed products like intelligent devices and sensors that can continuously monitor their infrastructure and surroundings. These include hazardous material sensors that measure toxic gas concentrations and equipment monitoring devices that record different machine variables that disclose the functioning of the equipment. This trend in workplace safety provides real-time data that enables managers and safety engineers to quickly identify any problems that could result in a potential hazard.

Every accident is the consequence of a series of events that culminate in infrastructure damage, injury, or even death. Process industries now have access to a large amount of data that can accurately reflect the status of a workplace at any given time owing to the digitization of workplaces. This information includes information from equipment sensors, employee records, environment sensors, and even surveillance shots. Artificial intelligence (AI) advancements provide solutions that harvest large data sets for knowledge to enhance worker safety and deliver predictive assessments. These approaches employ machine learning (ML) algorithms on previous data to identify trends that may be used as a guide to spot irregularities that could result in accidents. Thus, the trend toward workplace safety makes it easier to identify safety hazards early on and forecasts catastrophic failures, enabling maintenance managers to adopt proactive measures like preventative maintenance.

5 Endnotes

[1]        Ericson, C. A. (2015). Hazard analysis techniques for system safety. John Wiley & Sons.

[2]        Kaplan, S., and Garrick, G. (1981). On the quantitative definition of risk, Risk Analysis. In: vol.

[3]        Crawley, F., and Tyler, B. (2015). HAZOP: Guide to best practice. Elsevier.

[4]        Lees, F. (2012). Lees’ Loss prevention in the process industries: Hazard identification, assessment and control. Butterworth-Heinemann.

[5]        Wells, G. (1997). Hazard identification and risk assessment. IChemE.

[6]        Less, F. P. (2012). Loss prevention in the process industries: hazard identification, assessment and control (4th, Ed.). Butterworth-Heinemann.

[7]        Safety, C. f. C. P. (2011). Guidelines for hazard evaluation procedures. Wiley.

[8]        Safety, C. f. C. P. (2014). Guidelines for initiating events and independent protection layers in layer of protection analysis. In: Wiley Hoboken, NJ.

[9]        CCPS. (2013). Guidelines for enabling conditions and conditional modifiers in layers of protection analysis. American Institute of Chemical Engineers.

[10]      Zio, E. (2018). The future of risk assessment. Reliability Engineering & System Safety, 177, 176-190.

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