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Prevent and mitigate process hazards and safety risks with our expert PHA services

Effectively managing process hazards in the chemical, petrochemical, pharmaceutical, metal, pulp and paper, wood, food, and process industries has wide-reaching benefits for all stakeholders, including the employees, contractors, and the public. A Process Hazard Analyses (PHA) helps prevent injury, loss of life, and property and environmental damage that can result from industrial activity and is a primary tool for compliance with regulations such as OSHA 29 CFR 1910.119 (e). PHA is a proactive and structured approach by chemical process operations to understand what can go wrong, how likely it is to go wrong and what steps are necessary to prevent or mitigate undesired consequences.

Our process safety specialists with strong industry background can help you select the PHA method best suited to your specific processes and operations. With many years of experience in process safety, we are well heeled with the complexities of hazards analysis. We can assist you in accumulating the necessary process safety information including hazardous materials properties such as combustibility, flammability, explosivity, reactivity, self-heating, toxicity, electrostatic properties as well as assembling and leading the PHA team and drawing up reports and documenting outcomes.

As part of our focus on empowering our partners in matters of process safety, we offer in-house workshops to train employees to manage risk and be effective PHA leaders.

Practical solutions are at the heart of our approach. From offices around the world, our experts focus on each client’s particular situation, taking both a holistic and an individual view of PHA implementation. Services are available in English, Spanish, Chinese, French, German, Portuguese, Italian, Arabic and Hindi, among others.

A complete range of PHA methodologies

Our specialists are experienced in the full suite of process hazard analysis methods, including checklists, what-if checklists, Hazard and Operability Studies (HAZOP), Failure Mode and Effect Analysis (FMEA), Fault Tree Analysis (FTA), Layers of Protection Analysis (LOPA) and more. As each PHA method has pros and cons as well as varying scope and application, consulting with one of our experts before making a choice contributes significantly to the overall success of your PHA.

Process Hazard Analysis - Chilworth Technology
Our Process Hazard Analysis includes these four steps.

Whatever PHA methodology is chosen, the first phase of the analysis is dedicated to gathering all the applicable safety information about the materials handled, the chemical process and conditions, the control methods employed, and the equipment and systems use. The applicable safety information relevant to the targeted process are gleaned from Safety Data Sheets (SDS’s), laboratory testing, design manuals, operating procedures, and equipment manufacturers/suppliers.

Next, a team is assembled under the guidance of an experienced, knowledgeable leader which includes members with diverse experience and expertise to examine the process in search of inherent hazards and operating risks such as fire, explosion, and the release of materials or energy. During the PHA exercise for each hazard identified the team examines the existing safeguards that prevent or mitigate the undesired consequences in addition to proposing new measures should they be required.

The final critical aspect of the PHA effort is to provide adequate documentation of the analysis, its findings and recommendations. A risk management plan must follow the PHA in order to ensure that effective follow-up and closure occurs.

Meet with one of our PHA consultants and request a quote!

FAQ - Process Hazard Analysis

Process Hazard Analyses (PHAs) comprise a wide range of methods and require a certain level of preparation. We have assembled a selection of typical questions and answers to assist you in getting ready for the process, knowing what to expect and deciding on the right approach for you.

What are the steps for preparing for a PHA?

  1. Determine the scope and scope limitations
  2. Gather process safety information, including sample testing as needed
  3. Establish team composition, including a team leader who is “knowledgeable in the specific PHA methodology being used” ([OSHA)].
  4. Provide the team with PSI several days prior to the first meeting,
  5. Schedule the meetings for not more than four hours per day, such as two hours before and after lunch.

What are the different PHA methods?

  • Checklists
  • What-If
  • What-If/Checklist
  • Hazard and Operability Analysis (HAZOP), based on ”nodes” in the P&I diagrams, or steps in the operating procedure
  • Failure Modes and Effects Analysis
  • Fault Tree Analysis [FTA]

What are the criteria for selecting a PHA method?

  • Inherent hazards of materials
  • Status of the process ([development, or design, or in operation)]
  • System complexity
  • Availability of a previous analysis
  • Applicability of good codes, standards, and RAGAGEP to the scope
  • Availability of excellent site/corporate experience, such that a well-organized What-If will likely extract all process safety issues

Do not apply a more-complex method such as HAZOP to a well-defined system that is “covered” by good codes and standards such as a flammable liquid tank farm. Do not apply a more -complex and extreme-effort-intense method such as a FTA or a QRA unless there is a “criticalprofound” decision that has to be made concerning the safety of a process.

What are the must-have qualifications of a PHA team leader?

  • Expertise and experience in PHA methodology
  • Excellent understanding of the science of hazardous materials and the consequences of releases (could be brought to the team by a subject matter expert)
  • Good understanding of “unit operations” and the uses and functions of typical process equipment
  • Good people skills to manage the team and develop consensus
  • Good organizational skills to organize and document the effort

What makes a PHA great?

  • Appropriate methodology
  • Correct application of the methodology
  • Appropriate team composition including subject matter experts as needed
  • Excellent documentation that includes why a specific method is appropriate
  • Executive summary that summarizes why the operation is safe and what major opportunities for improvement exist
  • Good team participation
  • Well defined recommendations
  • Site follow-up with documentation of recommendation closure, with attachment to the PHA report

process safety mgt

Industry Background

Of the several “approved” types of Process Hazards Analysis (PHA), the “Hazard and Operability” (HAZOP) study is the most widely used PHA technique in the chemical, pharmaceutical, oil and gas, and nuclear industries worldwide. HAZOP is used during the design stages of a new process or project, for major process modifications, and for periodic review of existing operations. This method has been found to be very effective in identifying and analyzing the risks of potentially hazardous process operations and in identifying operability problems.

The Hazard and Operability (HAZOP) analysis methodology is a systematic team-based Process Hazards Analysis (PHA) technique.

The U.S. Occupational Safety and Health Administration (OSHA) recognizes the HAZOP technique as an acceptable methodology for conducting PHA’s of processes that are covered by the OSHA Process Safety Management standard. Other regulators around the world also accept the HAZOP methodology as appropriate for analyzing the existing and potential hazards of a complex process that involves a highly hazardous substance.

Although the HAZOP method is highly structured – in the application of Guide Words to Process Parameters – in practice, the quality of the study is influenced by the ability of the HAZOP Leader to ask the appropriate questions. The objective is to ensure that the team identifies all the hazards of the process being studied, not only the most obvious hazards. Thus, the outcome of the study is based on the Leader’s experience, with the HAZOP technique, with the process being analyzed, with process-control systems, and with unit operations, in general.

Our large team of highly-qualified HAZOP leaders and process-safety resource experts has facilitated hundreds of HAZOP-based PHA’s worldwide, in virtually all sectors of the process and processing industries. Our Team Leaders are chemical and/or process engineers with a high level of process safety expertise and knowledge, and with many years of experience leading HAZOPs in industry and as consultants.

We can facilitate HAZOPs, and other types of PHAs, in a large number of languages, including English, Spanish, Chinese, French, German, Italian, Arabic and Hindi. Our worldwide presence helps ensure intimate knowledge of local codes, standards, and cultures. Combined with our expertise in process safety engineering, material-testing capabilities, interpretation of test results, and ready access to process safety data, Chilworth provides a HAZOP capability unrivalled in our market.

Moreover, through the Chilworth Process Safety Academy, we train and qualify a large number of HAZOP leaders every year. We provide HAZOP leader training through our public-enrollment courses as well as private company training, which can be tailored to our clients’ specific needs.

Our Approach

Our approach is to use a structured HAZOP to identify the hazards of a process and – as a by-product – to identify potential operating problems. The emphasis is on evaluating the basic control system, providing effective emergency controls, preventing the release of hazardous materials, and mitigating the consequences of a loss of process control or a hazardous-material release. We provide a semi-quantitative HAZOP risk analysis that incorporates the philosophies of Layers of Protection Analysis (LOPA), Safety Instrumented Systems (SIL), and Fault Tree Analysis (FTA) to assess the reliability of process controls and number and type of risk reduction measures (safeguards) that might be needed.

The general steps involved in conducting a HAZOP include:

  • A review of the available Process Safety Information (PSI) and identification of missing PSI that is required to support the HAZOP, including:
    • Hazardous materials properties including combustibility, flammability, explosivity, reactivity, self-heating, toxicity, electrostatic properties
    • Process description
    • Process flow sheets
    • Operating procedures
    • Piping and instrumentation drawings (P&IDs)
    • Equipment design specifications
    • Pressure relief systems specifications
    • Site and industry data concerning process-component failure frequencies and probabilities of failure on demand (PFD).
  • The HAZOP study would involve the following procedure:
    • Establishing the “Design Intent” for the process, including the desired and/or safe ranges for each of the operating parameters
    • Applying the Guide Words (No, Less, More, Reverse, etc.) to each of the Process Parameters (Temperature, Pressure, Flow, Level, etc.), to identify deviations from the design intent
    • Determining if the control system and emergency systems are adequate and are sufficiently reliable to prevent each deviation from escalating to an undesirable process incident
    • Estimating the severity of the consequences of each undesired incident. Consequences can be further evaluated using our expertise in consequence modeling with specialist software such as PHAST® and Effects®
    • Estimating the likelihood of occurrence of each undesired incident
    • Utilizing a Risk Matrix to determine the relative risks of the undesired incidents
    • Comparing the risk of occurrence for each incident with corporate guidelines for process risk
    • Determining the number and types of safeguards and/or process improvements that would be needed to reduce the risks to negligible or tolerable risks
  • At the conclusion of the HAZOP analysis, our process safety specialist will present the results of observations, the findings and conclusions of the analysis, and preliminary recommendations and suggestions, to members of the site management staff.

Report and Documentation

Shortly after the HAZOP team’s study, the process safety engineer will submit a written draft report to the client that will contain the results of the study, for comments by the client. Our process safety specialist’s report will present the HAZOP Team’s recommendations and suggestions for improvements to the process, as based on the site’s experience and on recognized and generally-accepted good engineering practices. Following the receipt of comments from the client, a final report is issued.

layers of protection analysis (LOPA)

Using LOPA to examine risk levels of selected scenarios

Managing process safety means understanding the many factors that contribute to risk and establishing appropriate measures for risk mitigation. Layers of Protection Analysis (LOPA) is a method used to evaluate high-consequence scenarios determining if the combination of probability of occurrence and severity of consequences meets a company’s risk tolerance. LOPA addresses the key questions: “how safe is safe enough?”; “how many independent protection layers are needed?”; and “how much risk reduction should each layer provide?”

Our process safety specialists are comfortable with complexity and experienced in implementing the LOPA methodology. We provide rational, semi-quantitative risk-based answers to key questions as well as clarity and consistency among analyses of equipment and processes at plant sites. Documentation of each decision and the decision-making process is an integral part of our methodical approach. Upon completion of the analysis, the LOPA report promotes self-sufficiency by facilitating understanding among site personnel of process hazards and their prevention.

With a strong track-record in process safety, we have carried out countless Layers of Protection Analyses, gathering valuable experience to share with our clients. We place a premium on maintaining a global presence, providing services in a wide variety of languages and having a command of the local codes, standards and cultures. Combined with our intimate knowledge of process safety engineering and process safety data, we offer expertise unrivalled in the market.

A thorough approach to LOPA services

Typically, a high-consequence scenario – which usually involves a combination of equipment and human failures – is identified during a qualitative hazard evaluation, such as a Process Hazards Analysis (PHA) or a Hazard and Operability study (HAZOP). LOPA is then implemented for a closer, more careful assessment of this scenario. LOPA is a quantitative screening tool which provides a consistent, objective, and defensible approach.

A LOPA can be visualized as a series of slices of Swiss cheese, whereby each slice is a layer of protection with a varying number and size of holes representing flaws. A high-consequence scenario occurs only if at least one of the holes in each slice “line-up,” allowing propagation of multiple failures. For components of a process-control system, such as safety instrumented systems and other components such as relief valves and rupture disks, it is important to know or estimate the probability of failure on demand.

Layers of protection analysis - Chilworth Technology
Layers of protection scenarios

We study the process under investigation to identify likely initiating events and estimate the frequency of initiating-event occurrence. We will then examine all process-control features and safeguards, estimating the reliability of protection provided and ensure the independence of each protection layer. With this information, the likelihood of occurrence (or frequency) of a given high-consequence scenario can be semi-quantitatively determined. Combining this likelihood with the severity of the consequences, an evaluation of risk is obtained.

A risk matrix is usually employed to show the possible combinations of likelihood and consequence severity. The risk thus obtained can be compared to the facility or corporation’s risk tolerance for presentation to site and/or corporate management. We prepare a comprehensive study report to serve as a record of the completed analysis, including descriptions of potential risks with the existing safeguards and with recommendations for additional safeguards, where warranted.

Let us share how our LOPA services can benefit your company. Contact us today.

process safety mgt

Chilworth Process Safety Engineers can provide auditing of all aspects of your Process Safety Management (PSM), Risk Management Plan (RMP), and New Jersey Toxic Catastrophe Prevention Act (NJTCPA) programs. The audits can be performed to determine conformance to OSHA – Occupational Safety and Health Standard (29 CFR 1910.119), Process Safety Management of Highly Hazardous Chemicals, EPA’s risk management rule (40 CFR Part 68), Chemical Accident Prevention Provisions, the NJTCPA Consolidated Rule, or your corporate process safety standards and programs.

A Chilworth audit will follow a three-step process:

Step 1 Information Collection

Our safety engineers work closely with site personnel to collect pertinent Process Safety Information required for the audit. Time spent on this activity helps to minimize the time required for the on-site visit. Information needed may include process descriptions and flow diagrams, material property data, site equipment layout drawings, and written policies and procedures.

Step 2 Site Visit

The auditor will visit the site for a physical audit. During this visit, the auditor will complete record reviews, make visual observations, and conduct interviews with site operations and maintenance personnel, as well as contract personnel, in order to assess compliance. For OSHA, EPA, and NJTCPA compliance, a detailed checklist will be completed following all aspects of the standards.

Step 3 Report and Documentation

The auditor will submit a written report to the client that will contain findings, checklists, observations, and suggestions concerning any deficiencies found in the PSM, RMP, and/or NJTCPA covered portions of the site. The Chilworth safety engineer will offer insight and recommendations as may be required to advance the site’s programs based on the legislated requirements and best industry practices.

process safety mgt

The management of process hazards in the chemical, petrochemical, pharmaceutical, and process industries has become an increasing and world-wide concern of many stakeholders, including the public, legislators, employees, and contractors. In response to serious incidents, regulations have been enacted in many countries to establish management systems that identify and control process hazards.

As a Trusted Advisor, we assist our clients in not only meeting the legislated requirements for process safety management, but also support corporate concerns for safety of on-site personnel and the community that exceed minimum regulatory requirements. This is accomplished by applying the global Process Safety expertise of Dekra Insight to focus on developing and supporting an effective set of Process Safety management practices specific to a client’s hazards.

Our approach

Process Safety Management (PSM) regulations (as examples: OSHA 1910.119 in the U.S., and SEVESO Directive in Europe), and industry guidelines from many professional associations (such as the Center for Chemical Process Safety) drive PSM practices. Our services are designed to help companies comply with these PSM requirements, by providing information that allows the selection and implementation of the most effective practices for each client. Our approach looks holistically at Process Safety Management Systems, Proficiency of Facility Staff at All Levels, and Organizational Culture. Our experience has shown that this broader view of Process Safety helps ensure that a PSM program:

  • Fits seamlessly into our clients’ business models and operations,
  • Is accepted and embraced by corporate management, staff, and employees,
  • Becomes a real part of a company’s culture, and
  • Is successfully implemented throughout the lifecycle of operations, to lower process risks.

Our experience, methodologies and expertise

Our PSM consultants are process, chemical, and safety engineers with strong industry backgrounds, complemented by in-depth expertise in process safety. Through our global offices, located in twelve offices worldwide, we offer and can tailor the following PSM services to your needs:

  • Process Safety Management (PSM) Program Development, Implementation and Improvement
  • PSM Auditing and Compliance-Gap Identification (OSHA, Seveso, CCPS Risk Based Process Safety, and others)
  • Dekra Insight Process Safety Academy, which provides a comprehensive PSM competency development program for employees at all levels.
  • Assessment of Process Safety Culture & Organizational Reliability
  • Process Hazard Analysis (HAZOP, LOPA, HAZID, What-if, Checklist, FMEA, Bow Tie, Fault Tree)
  • Quantitative Risk Assessment (QRA), including Consequence Modeling
  • Facility Siting Studies
  • Process Safety Information compilation, and assessment of adequacy
  • Laboratory testing capabilities, to assess and document reactivity and flammability hazards.
  • PreStart-Up Safety Reviews (PSSR)
  • Evaluation of Non-Routine Operations and Permitting Procedures
  • Evaluation of Emergency Plans and Practices
  • Building Code & Fire Code Hazardous Materials Reviews
  • Develop & Review Major Accident Hazard Safety Case Reports
  • Evaluation of SEVESO Compliance Reports
  • Technical and Organizational Procedural/Administrative Hazard-Control Measure Assessment
  • Evaluation of the Safety Features in Process Design and Control
  • Study of Operating and Maintenance Practices in the Field
  • Assistance in the Investigation of Fire, Explosion, Reactivity, and PPE-Inadequacy Incidents
  • Support in Litigation, as Expert Witness

Our PSM services are supported by our worldwide offices, and are available in a wide variety of languages, including English, Spanish, Chinese, French, German, Portuguese, Italian, Arabic and Hindi.

Laboratory Testing

lab testing

We operate one of DEKRA's world premier chemical process hazards laboratories. Process safety testing is used to develop the data on which fire and explosion hazard assessments and incident investigations should be based.

Learn about our Laboratory Testing options