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This page contains previous items from our Latest News feature.

Primatech's Dr. Paul Baybutt authors paper on a critique of the HAZOP study

Publish Date: 2015-02-25
Category: Primatech News

The paper was published in the Journal of Loss Prevention in the Process Industries, Chemical Engineering Progress, Vol. 33, pages 52 - 58, January 2015.


Conventional wisdom holds that the Hazard and Operability (HAZOP) study is the most thorough and complete process hazard analysis (PHA) method. Arguably, it is the most commonly-used PHA method in the world today. However, the HAZOP study is not without its weaknesses, many of which are not generally recognized. This article provides a critique of the method to assist study teams in compensating for them to the extent possible and to help guide the development of improved methods.

Primatech Presentations at the 2015 Global Congress on Process Safety

Publish Date: 2015-02-17
Category: Primatech News

The following presentations will be delivered by Primatech at the upcoming 2015 Global Congress on Process Safety to be held at the Austin Convention Center in Austin, Texas:

  • The Psychology of Decision Making in Process Hazard Analysis by Paul Baybutt, Convention Center Ballroom E, 8:00 AM Tuesday, April 28.
  • Addressing Issues in the Design and Use of Risk Matrices in Process Safety by Paul Baybutt, Convention Center Room 17A&B, 9:00 AM Wednesday, April 29.

Plan on attending and mark your calendars. You can register for the Congress at:


HSE Report on Source Terms for Flashing Releases

Publish Date: 2015-02-02
Category: Industry News

ACE (Airborne Concentration Estimate) is a model developed for computing source terms arising from instantaneous flashing releases. The model has been enhanced through a series of extensive tests that have been performed by the UK Health and Safety Executive's (HSE's) Health and Safety Laboratory.

Inputs to ACE are the substance, its mass and storage conditions, and ambient weather conditions. The model computes the formation of a vapor cloud assuming total loss of containment. This is done in two distinct stages: an explosion phase, which models the initial flashing process, and a turbulent growth stage, which describes further radial expansion and air entrainment. The resulting cloud properties can be used as the input to an atmospheric dispersion model.

The report, RR1028, Further validation of the ACE instantaneous source model, describes an updated validation of the ACE model in which overall cloud radius predictions have been compared with those obtained from experiment. Further validation was addressed by comparing cloud expansion velocities.

The report is available at:


Primatech's Dr. Paul Baybutt authors paper on addressing chemical reactivity in PHA

Publish Date: 2015-01-30
Category: Primatech News

The paper was published in Chemical Engineering Progress, Vol. 111 (1), pages 25 - 31, January 2015.


Reactive incidents have been defined by the U.S. Chemical Safety Board as sudden events involving an uncontrolled chemical reaction - with significant increases in temperature, pressure, and / or gas evolution - that have caused, or have the potential to cause, serious harm to people, property, or the environment. Unfortunately, they occur regularly in the process and other industries, often with catastrophic consequences.

Significant work has been performed on understanding chemical reactivity hazards but much less attention has been paid to the identification of reactivity hazard scenarios using process hazard analysis (PHA). This paper discusses the consideration of chemical reactivity hazards in PHA and explains how reactivity hazard scenarios can be identified in PHA. Pitfalls in performing PHA that address chemical reactivity hazards are also identified so that analysts can endeavor to avoid them.

Primatech's Dr. Paul Baybutt will be teaching a new one-day short course entitled "Developing and Implementing a Competence Management Program for Process Safety" at the upcoming CCPS 11th Global Congress on Process Safety in Austin, Texas.

Publish Date: 2015-01-21
Category: Primatech News

Process safety personnel play a critical role in protecting lives, property, the environment and company reputations. The competency of such personnel must be managed to ensure companies achieve adequate levels of safety and tolerable levels of risk. Course participants will gain an understanding of how a competence management program for process safety can be developed and implemented.

Click here for more details. http://www.aiche.org/ccps/conferences/global-congress-on-process-safety/2015/events/11th-gcps-short-courses#risk tolerance criteria

Registration is available through CCPS at:

Email: customer_service@aiche.org

Tel: +1 (800) 242-4363

CSB Releases Safety Bulletin on Anhydrous Ammonia Incident Involving Hydraulic Shock

Publish Date: 2015-01-19
Category: Industry News

On January 15, 2014, the U.S. Chemical Safety Board (CSB) released a safety bulletin for industries that utilize anhydrous ammonia in bulk refrigeration operations on how to avoid a hazard referred to as hydraulic shock. The safety lessons were derived from an investigation into an accidental release of anhydrous ammonia that occurred on August 23, 2010 from a Millard Refrigerated Services Inc. facility located in Theodore, Alabama.

The accident involved two ships that were being loaded when the Millard facility's refrigeration system experienced hydraulic shock, which is a sudden, localized pressure surge in piping or equipment resulting from a rapid change in the velocity of a flowing liquid. This abnormal transient condition results in a sharp pressure rise with the potential to cause catastrophic failure of piping, valves, and other components. Prior to a hydraulic shock incident, often there is an audible "hammering" in refrigeration piping. The incident at Millard caused a roof-mounted 12-inch suction pipe to fail catastrophically resulting in the release of more than 32,000 pounds of anhydrous ammonia. Thirty two workers required hospitalization, four of them in an intensive care unit.

The Safety Bulletin, entitled "Key Lessons for Preventing Hydraulic Shock in Industrial Refrigeration Systems", notes five key lessons to prevent hydraulic shock. It is available at:


Primatech's Dr. Paul Baybutt authors two letters to the editor

Publish Date: 2015-01-19
Category: Primatech News

One letter addresses confusion in the literature on terminology for process safety, security, and risk management, particularly the meaning of process hazard analysis, and the need for consistent usage of terms. The other letter addresses the need to transform OSHA's process safety management standard into a performance-based and risk-based standard using a management systems framework.

The letters were published in the December, 2014 issue of Process Safety Progress, Volume 33, Issue 4, pages, 405-­407.

Primatech's Dr. Paul Baybutt authors paper on requirements for improved PHA methods

Publish Date: 2015-01-12
Category: Primatech News

The paper was published in the Journal of Loss Prevention in the Process Industries, Vol. 32, pages 182-191, November, 2014.


In order to develop better process hazard analysis (PHA) approaches, weaknesses in current approaches first must be identified and understood. Criteria can then be developed that new and improved approaches must meet. Current PHA methods share common weaknesses such as their inability specifically to address multiple failures, their identification of worst-consequence rather than worst-risk scenarios, and their focus on individual parts of a process. There has been no comprehensive analysis of these systemic weaknesses in the literature. Weaknesses are identified and described in this paper to assist in the development of improved approaches. Knowledge of the weaknesses also allows PHA teams to compensate for them to the extent possible when performing studies.

Key criteria to guide the development of improved methods are proposed and discussed. These criteria include a structure that facilitates meaningful brainstorming of scenarios, ease of understanding and application of the method by participants, ability to identify scenarios efficiently, completeness of scenario identification, exclusion of extraneous scenarios, ease of updating and revalidating studies, and ease of meeting regulatory requirements. Some proposals are made for moving forward with the development of improved methods including the semi-automation of studies and improvements in the training of team members.

Primatech's Dr. Paul Baybutt authors paper on competency requirements for PHA teams

Publish Date: 2014-12-16
Category: Primatech News

The paper was published in the Journal of Loss Prevention in the Process Industries, Vol. 33, pages 151-158, January, 2015.


Process hazard analysis (PHA) is a cornerstone of process safety management programs. The quality of the PHA performed directly affects the level of risk tolerated for a process. The lower the quality of a PHA, the more likely higher risk will be tolerated. There are few requirements for PHA team members in the U.S. Occupational Safety and Health Administration's process safety management regulations. More detailed requirements for participation in a PHA are desirable.

A competency management program should be used to ensure PHA practitioners and teams are appropriately qualified. Criteria for selecting PHA team leaders, or facilitators, and other team members are key to such a program and are described in this paper. The criteria cover both technical and personal attributes. Application of the criteria is described and team performance metrics, which can be used to correlate performance with the assessment of competency to validate the criteria and methods used, are discussed.

Owing to the importance of the role played by team leaders, certification of their competency is desirable.

The paper can be accessed for free on ScienceDirect until January 30, 2015 by clicking on the link below. No sign up or registration is needed.


OSHA Testifies at Joint Senate Committee Hearing

Publish Date: 2014-12-12
Category: Industry News

On December 11, 2014, David Michaels, Assistant Secretary, Occupational Safety and Health Administration (OSHA), testified before the Senate Committees on Health, Education, Labor and Pensions, and Environment and Public Works regarding the improvement of chemical facility safety and security at hazardous chemicals facilities.

Dr. Michaels stated that in the past five years at least 28 significant process-safety-related incidents have occurred resulting in over 75 fatalities, multiple injuries, and extensive consequences for workplaces and communities. He testified that OSHA's National Emphasis Program (NEP) for Process Safety Management (PSM) that was initiated in 2007 to address the hazards of petroleum refineries found a widespread and deeply troubling failure to comply with basic PSM principles in many refineries. Dr. Michaels also testified that, in light of the experience gained from the Petroleum Refinery NEP, OSHA initiated the Chemical Facility National Emphasis Program for PSM in 2011 to focus on facilities that present the potential for catastrophic incidents. Since then, OSHA has conducted 645 inspections under the Chemical Facility NEP and OSHA compliance personnel have found more than 3,100 violations of OSHA standards, primarily in PSM.

Dr. Michaels stated that although OSHA believes that the Refinery and Chemical Facility NEPs encouraged employers to build more robust chemical process safety systems, and ultimately prevented releases of highly hazardous chemicals, much more needs to be done. He testified that OSHA has slightly more than 2,000 inspectors to cover workplace safety and health in over 7 million workplaces across the country. Process safety management inspections are more resource intensive than most other OSHA inspections, and OSHA is limited in the number of chemical facilities that can be inspected in any given year. As a result, OSHA must explore other strategies.

Dr. Michaels testified that, while OSHA, industry, and labor generally agree that the PSM standard has been effective in reducing process safety incidents, major incidents continue to occur. Dr. Michaels stated that the PSM standard is over 20 years old and that modernizing the standard will allow OSHA to overcome obstacles to effective enforcement of the standard, implement advances in industry recognized best practices, and protect workers from process safety hazards that were previously not covered.

Dr. Michaels stated that OSHA's enforcement experience over the past two decades suggests that a number of potential regulatory and policy improvements would improve PSM compliance as well as enforcement and oversight of facilities covered by the PSM standard. Among other things, as part of the PSM rulemaking process, Dr. Michaels stated that OSHA plans to consider:

  • Clarifying the PSM standard to incorporate lessons learned from enforcement, incident investigation, and advancements in industry practices, for example, root cause analysis, process safety metrics, enhanced employee involvement, third party audits, and emergency response practices.
  • Adding substances or classes of substances to the PSM Appendix A highly hazardous chemicals list and providing more expedient methods for future updates.
  • Expanding coverage and requirements for reactive chemical hazards, which have resulted in many incidents. There has been a long history of incidents resulting from reactivity hazards, but regulatory coverage remains a technically complex issue. OSHA is looking at different options and considering other models such as that implemented by the State of New Jersey.
  • Covering oil and gas drilling and servicing work explicitly. The upstream oil and gas production has one of the highest fatal injury rates of any industry, and more needs to be done to protect the health and safety of that industry's workers.
  • Requiring analysis of safer technology and alternatives, in coordination with EPA's activities under the RMP. OSHA finds that employers can make their processes safer by incorporating a combination of risk reduction analysis and hierarchy of control techniques that are currently industry best practices.
  • Requiring coordination between chemical facilities and emergency responders to ensure that emergency responders know how to use chemical information to safely respond to accidental releases, possibly including exercises and drills.

Dr. Michaels stated that OSHA's PSM standard and EPA's RMP regulation were promulgated at about the same time, pursuant to the Clean Air Act Amendments, to address similar underlying general hazards. Yet, the OSH Act's penalty provisions are much weaker than those under the Clean Air Act's RMP program. Dr. Michaels testified that this imbalance in penalties should be corrected by strengthening the OSH Act's civil monetary penalties and indexing them for inflation and, in addition to increased civil monetary penalties, the criminal penalty provisions of the OSH Act should be strengthened to provide a credible deterrent in order to achieve greater compliance with workplace safety and health standards.

As a next step towards developing a proposed rule to modernize the PSM standard, OSHA plans to initiate the Small Business Regulatory Enforcement Fairness Act review by mid 2015 in order to solicit small business views on modernizing the PSM standard.

Further details can be found at: