How Can We Help You?

We work collaboratively with our clients to provide them excellence in process 
design, safety analysis, project engineering and management, and other 
technical and professional services.

What is a PHA?

One of the 14 elements of a Process Safety Management program, a Process Hazard Analysis, or PHA, is a systematic evaluation of potential hazards associated with an industrial process, helping plant personnel make informed decisions to improve safety and reduce consequences of unwanted or unplanned releases of hazardous chemicals.  During a PHA, potential causes and consequences of fires, explosions, releases of toxic or flammable chemicals and major spills of hazardous chemicals are analyzed with focus on equipment, instrumentation, utilities, human actions, and external factors that might impact the given process.  A properly facilitated and documented PHA also helps protect against process downtime, property damage, product quality issues, and large-scale accidents.


PHA methods are qualitative in nature. The selection of a methodology to use depends on a number of factors, including the complexity of the process, the length of time a process has been in operation, if a PHA has been conducted on the process previously, and if the process is unique or industrially common.


There are many methodologies that can be used to conduct a PHA, including but not limited to:

  1. Checklist

  2. What If?

  3. What If? / Checklist

  4. Hazard and Operability study (HAZOP)

  5. Failure Mode and Effects Analysis (FMEA)

  6. Fault Tree Analysis (FTA)


In the United States, the use of PHAs is mandated by the Occupational Safety and Health Administration (OSHA) in its process safety management regulation (29 CFR 1910.119) for the identification of risks involved in the design, operation, and modification of processes that handle highly hazardous chemicals.  Companies that handle or process highly hazardous chemicals have a responsibility to protect employees, the public and the environment from exposure to accidental releases.






What is a LOPA?

A Layer of Protection Analysis (LOPA) is a recently developed, simplified method of risk assessment that provides a much-needed middle ground between a qualitative process hazard analysis (PHA) and a traditional quantitative risk analysis (a SIL Selection, for example). 


Beginning with an identified accident scenario that is typically identified during a PHA, LOPA uses simple rules to evaluate initiating event frequency, independent layers of protection (IPLs), and consequences to provide an order-of-magnitude estimate of risk.  LOPA has also proven an excellent approach for determining the safety integrity level necessary for an instrumented safety system, an approach endorsed in instrument standards, such as ISA S84 and IEC 61511.  A LOPA can be performed during any stage in a processes' life cycle.  Due to its simplified, quicker risk assessment approach, LOPA has quickly become a widely used technique.


LOPA is not just another hazard assessment or risk assessment tool.  It is an engineering tool used to ensure that process risk is successfully mitigated to an acceptable level.  LOPA is a rational, defensible methodology that allows a rapid, cost effective means for identifying the IPLs that lower the frequency and/or the consequence of specific hazardous incidents.  LOPA provides specific criteria and restrictions for the evaluation of IPLs, eliminating the subjectivity of qualitative methods at substantially less cost than fully quantitative techniques.

How Can We Help?

Integral Engineering Group can provide an experienced facilitator and/or technical scribe to work with plant personnel who are intimately familiar with the process being analyzed.  The facilitator prepares for the analysis prior to the team meetings, systematically breaking the scoped process into smaller, more easily evaluated systems.  Additionally, the facilitator will aid in the selection of client team members, determine the appropriate analysis methodology, and oversee the team's discussion of causes and consequences of possible accidents.  At the conclusion of the analysis, IE Group will provide thorough documentation of the study and provide recommendations for appropriate corrective actions as needed.


IE Group personnel have conducted PHAs and LOPAs in several industries, including the oil and gas, nuclear, and specialty chemical industries.  We have facilitated hundreds of studies using the various techniques listed above, including .  Our team is proficient in the use of several industry-accepted analysis documentation programs, including PHA Pro, PHA Leader, and PHAx.

We provide facilitators to conduct and lead various typis of process and hazard and risk analyses per OHSA 29 CFR 1910.119 and EPA 40 CFR Part 68):​

  • Hazards Analysis

    • Process Hazard Analysis (Design, Initial, Revalidation)​

    • Probablistic Hazard Analysis

    • Dust Hazard Analysis

    • Management of Change

  • Layers of Protection Analysis​

  • Safety Integrity Level (SIL) Selection Analysis

If you have any questions or would like any additional information on our Process Hazard and Risk Analysis services, please do not hesitate to Contact Us.