Safety Moment #106: Process Safety Assessments

This Safety Moment discusses the distinction between Process Safety Assessments and Process Safety Audits. It provides guidance to do with the development of Assessment protocols. Audits Audits are a fundamental feature of all successful management programs. Line managers need to know how they are performing, and senior management needs a means of checking that all the rules and standards are…

Safety Moment #105: Process Safety Wisdom

This Safety Moment is one in a series to do with the process safety profession. Other publications in the series are Safety Moment #54: The Process Safety Professional, Safety Moment #79: The Process Safety Consultant and Chapter 20 of the book Process Risk and Reliability Management. Further guidance is also provided in the ebook 52 Process Safety Moments which contains Safety Moment #22: Clear…

Safety Moment #104: Behavior-Based Safety

A behavior-based safety (BBS) program aims to make permanent changes in the manner in which people work. Safety becomes a way of life that is baked into everyone's behavior. It is important to recognize, however, that a BBS program does not attempt to chance who a person is, and it most certainly is not a pop-psychology program. The program is directed just to a person's actions. BBS helps…

Safety Moment #103: Human Error Modeling

Human performance is inherently unpredictable. Human beings are, after all, human. However, those working in industrial risk management have developed means of modeling types of human error, and the rates at which they can occur. One such technique is known as THERP (Technique for Human Error Rate Prediction). The method uses Boolean logic to model and predict human error rates. Hence it can be…

Safety Moment #102: ALARP and Acceptable Risk

Fundamentally risk is subjective; it is not possible to define what level of risk is acceptable dispassionately and objectively. Any two risk scenarios are inherently different from one another due to people’s inherent understanding and acceptance of different types of risk, their emotions, memories, hopes and fears. Factors that affect risk perception include the following: Degree of control…

Safety Moment #98: Types of Fire

The material in this article is taken from Chapter 12 of the 2nd edition of the book Plant Design and Operations. The first step in the design and development of a system to prevent, control and extinguish fires is to identify the various release scenarios that could lead to an explosion and/or fire. This is often done through use of a hazards analysis technique such as HAZOP (Hazard and…

Safety Moment #97: Stairways and Ladders

The material in this article is extracted from Chapter 2 of the 2nd edition of book Plant Design and Operations. When developing the layout for a facility it is very important to ensure that personnel can move around quickly and safely using stairways, ladders, platforms and ramps. They should also be able to use the stairways and ladders to move maintenance equipment and tools, as needed and…

Safety Moment #96: Safety Signs

The material in this Article is extracted from Chapter 16 (Human Factors and Ergonomics) of the book Plant Design and Operations. Guidance as to the types of signs and their meanings is provided below. Prohibition Prohibition signs mean "You must not" or "Do not do . . ." or "Stop". Signs of this type have a red circle, a white interior and a red bar, as illustrated in Figure 16.4. Figure 16…

Safety Moment #94: Fault Tree Analysis

This Safety Moment provides an initial overview of the topic of Fault Tree Analysis (FTA). The technique is described in detail in the book Process Risk and Reliability Management. Risk Analysis Risk can be analyzed in one of two basic ways: inductively or deductively, that is either bottom-up or top-down. In a deductive analysis a top-level system failure is postulated. The analyst then works…

Safety Moment #93: The Fundamentals of Risk

Risk This article discusses risk fundamentals in the process and energy industries.The word 'risk' has a wide range of meanings. In the context of process plant management it can be categorized in one of three ways. The first type of risk is to do with catastrophic events and serious safety violations. They can also have a major effect on a company's financial performance to the point where the…

Safety Moment #91: Lockout Tagout

Lockout / tagout systems are routinely used to protect workers when they are working with or close to hazardous systems. They are typically used in conjunction with the other isolation methods. Once a switch or valve is in the correct position it is locked so that it cannot be moved, and a 'Do Not Operate' tag is attached to it. (Valves are often chained in place, with the lock being used to…

Safety Moment #89: Layout of Process Facilities

Siting The words ‘siting’ and ‘layout’ are often used interchangeably, but, strictly speaking, they have different meanings. Siting is concerned with the location of a facility. For example, if a company is planning on building a new chemical plant its management may consider the relative merits of sites in Texas, Mexico or China. Layout, on the other hand, is to do with the locations of…

Safety Moment #88: Blinds in Process Piping

 Isolation Methods Positive isolation methods are those which remain effective even if there is equipment failure or operator error. These techniques apply not only to vessels, piping and tanks but also to pneumatic and hydraulic equipment. The sketch shows some of the various isolation techniques that can be used to protect workers in the process industries. The process containing toxic or…

Safety Moment #87: Hydrogen Sulfide

Hydrogen Sulfide Hydrogen Sulfide is a highly toxic chemical compound that is found in a wide variety of oil processing operations. High concentrations of H2S may be present in crude oil, molten sulfur, tank and pit-bottom sludge and produced water, all of which may release H2S when agitated, heated, or depressurized. Typical operational activities where personnel may be exposed to H2S include…

Safety Moment #84: Prestartup / Operational Readiness Reviews

The purpose of a Prestartup / Operational Readiness Review (PSR) is to ensure that initial start-ups, or start-ups following major project work, proceed safely and smoothly. In particular, the PSR will check to make sure that all project activities are complete and that the system is ready for safe operation. It is a tool that the operations and maintenance departments use to make ensure that…

Safety Moment #83: The One-Legged Stool

Reproduced with permission Early in the 20th century a factory in the town of Pitsea in England manufactured the explosives using nitro-glycerine.  Making nitro-glycerine was very dangerous. Concentrated acids were mixed with glycerine in huge vats. If too much glycerine was added too quickly to the mixture, it would become unstable, and a large valve would have to be opened to quickly dump…

Safety Moment #82: Confined Space Entry

A Confined Space is a space which is large enough for a worker to enter but has limited openings for entry and exit and is not intended for continuous employee occupancy. Entry is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space. Therefore it is not permissible, for example, to take a quick breath and to put one's head into a…

Safety Moment #81: Process Safety Fundamentals

Many of the publications that we offer are to do with the topic of Process Safety Management (PSM), or with related topics such as the offshore Safety and Environmental Management System (SEMS) and Safety Cases. An overview of the topic of Process Safety Management is provided here. Much more detail is available in the books Process Risk and Reliability Management and Offshore Safety Management…

Safety Moment #80: Not the Whole Truth

Safety professionals are rightly making increasing use of photographs and videos to train and educate the workforce, and to analyze incidents. In particular, security cameras often provide a fine record of an event as it unfolds. However, it is important to be careful. Not only can images be deliberately changed, but the camera may not record everything of relevance. The following set of…

Safety Moment #79: The Process Safety Consultant

This Safety Moment is one in a series to do with the process safety profession. Other publications in the series are Safety Moment #54: The Process Safety Professional, Safety Moment #105: Process Safety Wisdom and Chapter 20 of the book Process Risk and Reliability Management. Further guidance is also provided in the ebook 52 Process Safety Moments which contains Safety Moment #22: Clear Your…

Safety Moment #77: NORM (Naturally Occurring Radioactive Material)

NORM (Naturally Occurring Radioactive Material) is found in many naturally-occurring materials, including some oil and gas deposits. Sources of NORM include: Uranium; Thorium;  Radium; and Lead-210 When NORM is transported to the surface in production streams it can precipitate and accumulate inside tubing strings, surface equipment and piping as sulfate and carbonate deposits. NORM can…

Safety Moment #76: Plugged Process Piping

Process lines, piping and valves frequently become plugged. If line pluggage is a recurring problem it is best to try and identify ways in which the problem can be prevented from occurring. If that solution is not possible then valves, drains, tees and connections should be designed so that it is possible to remove the pluggage safely and with minimum time and expense. Prevention of Pluggage It…

Safety Moment #75: Pressure Tests

After a piece of equipment or piping that operates under pressure has been opened and then reassembled (buttoned up) it must be pressure tested before being put back into service. There are two types of pressure test. The first is a tightness or leak test, performed after the equipment has been opened but not modified in any way. Typically this type of test is conducted after the item was opened…

Safety Moment #74: Contractors in the Process Industries

   For further information on this topic, please refer to our ebook Contractors. Contractors play a vital and increasingly important role in the design, construction, operation and maintenance of process and energy facilities, as can be seen from the chart shown below. It can be seen that, over the last twenty years or so, the number of contractor work hours has increased by about a fact of…

Safety Moment #73: Storage Tanks in the Process and Energy Industries

Storage tanks are widely used in the process industries to store liquids that are below their boiling point at atmospheric temperature (some tanks may be insulated and they may have heating or cooling coils to maintain the temperature of the liquid that they are storing). Typically, tanks are either open to the atmosphere or to a system such as a flare or vent header that is at atmospheric…

Safety Moment #69: That Would Be Telling

The Kletz Legacy One of the founders of the process safety discipline was Trevor Kletz (1922-2013). Probably his best eulogy is also the simplest, "He saved lives." As we reflect on Trevor's contributions it is clear that one of his greatest gifts was that of telling stories. He wrote extensively on technical topics such as hazards analysis and inherent safety, but he is probably best…

Safety Moment #67: The Most Important PSM Elements — Management of Change

All elements of process safety management (PSM) are important, and they all interact with one another. However, it is suggested that three of the elements are of particularly high importance. They are employee participation, hazards analysis and management of change (MOC).  Safety Moment #66: The Most Important PSM Elements — Participation, Safety Moment #67: The Most Important PSM Elements…

Safety Moment #66: The Most Important PSM Elements — Participation

In an earlier Safety Moment we saw that the term ‘Process Safety Management’ (PSM) can become diluted to the point where it loses any meaning. This is unfortunate. The term is not just another way of describing industrial safety — it has a tight and specific significance, as explained in Process Safety Management. The description discusses the three words that make up the term: ‘Process’, ‘Safety…

Safety Moment #65: Personal Protective Equipment (PPE)

Personal Protective Equipment (PPE) is the last line of defense for keeping a person safe. Every effort should be made to protect the wearer ahead of time. The Irish Health & Safety Authority provides the following precautionary statements with regard to PPE. PPE only protects the wearer. It is ineffective if not working or fitted properly. Theoretical levels of protection are seldom…

Safety Moment #64: Equipment Spacing (Hydrocarbon Storage Tanks)

Safety Moment #57: Equipment Spacing (Pumps/Fireproofed Pipe Racks) described the layout of pumps in a process or energy facility. Continuing the discussion, this Safety Moment describes some of the issues to be considered with regard to the layout of storage tanks, sometimes referred to as “API Tanks”. (The design and operation of storage tanks is discussed in Safety Moment #73: Storage Tanks in…

Safety Moment #62: From Complicated to Complex

In any performance-based program such as process safety, the work is never finished — there is always room for improvement. Nevertheless, the developments that are being made are mostly to do with improving existing programs or techniques. For example, the hazards analysis technique LOPA (Layers of Protection Analysis) has seen widespread application in recent years. Yet it is basically a…

Safety Moment #60: Risk Perception

The material in this article to do with risk perception is taken from the book Process Risk and Reliability Management. Oscar Wilde Risk perception is fundamentally a subjective matter; no matter how hard analysts strive to make the topic objective the fact remains that, as Oscar Wilde  (1854-1900) once said, A truth ceases to be a truth as soon as two people perceive it.  This observation…

Safety Moment #59: In-Kind / Not In-Kind Change

The topic of Management of Change (MOC) is discussed in the following publications: Safety Moment #5: Management of Change — Defining Change and Safety Moment #67: The Most Important PSM Elements - Management of Change In this Safety Moment we look more deeply into the distinction between “In-Kind” and “Not In-Kind” changes. In principle, this distinction is simple. If the replacement for…

Safety Moment #58: Fukushima-Daiichi - Two Too Many Common Causes

This analysis do with the catastrophic incident at the Fukushima-Daiichi nuclear power plant was first published as an article at this site in the year 2017. The event itself took place on March 11th 2011. At first it was headline news. Then publicity to do with what happened receded into the background and new crises came to the fore, and captured our imaginations. Yet the event provides…

Safety Moment #57: Equipment Spacing (Pumps/Pipe Racks)

Pump seals are a frequent source of leaks in process and energy facilities. Moreover, the discharged liquid will normally be at high pressure, so it can travel a long distance and/or form a spray. Therefore, when laying out a facility it is important to make sure that pumps are located at a safe distance from other equipment and piping. (If the facility is already constructed and in operation it…

Safety Moment #56: Sinking Standards / Accountants Rule the Waves

This month is the 30 year anniversary of the Piper Alpha disaster. And, as to be expected, many people have published articles, blogs and web pages to do with that event, and the lessons that it continues to teach us. But there is an earlier maritime event which probably had a greater impact in its day than did Piper Alpha in ours. And that event was the sinking of the Titanic. (The image at the…

Safety Moment #55: Lifeboat Fall

This YouTube video shows an incident in which one man died and six others suffered lost-time injuries. Briefly, this is the time line. The seven men boarded a lifeboat as part of a safety drill. The lifeboat was launched without incident. The lifeboat was then retrieved with the men still on board. As the vessel approached the top of the davits the on-load release mechanism failed. The aft…

Safety Moment #54: The Process Safety Professional

This Safety Moment is one in a series to do with the process safety profession. Other publications in the series are Safety Moment #79: The Process Safety Consultant, Safety Moment #105: Process Safety Wisdom and Chapter 20 of the book Process Risk and Reliability Management. Further guidance is also provided in the ebook 52 Process Safety Moments which contains Safety Moment #22: Clear Your…

Safety Moment #53: Slug Catchers

The fluids flowing through many pipelines are two phase, i.e., a mixture of liquid and gas. Ideally the two phases separate out with the liquid at the bottom section of the pipe. The two phases flow together to a processing facility that separates the two phases. In practice, however, the two phases often travel at different rates which means that they can form slugs whereby the composition of…

Safety Moment #12: The (Process Safety) Two Second Rule

The Two Second Rule is used in driver training. It states that a driver should stay at least two seconds behind any vehicle that is directly in front of his or her vehicle. This is because most drivers require at least two seconds in which to respond to a sudden or emergency situation. The concept of a “two second rule” can also be used in process safety management programs. For the complete…

Safety Moments for the Process and Energy Industries

Safety Moments Safety Moments are short presentations that illustrate some aspect of personal or process safety. They are often used to start a meeting. They generally fall into one of the following categories: An incident analysis that provides lessons learned; A discussion to do with the principles of process safety management; or An explanation of equipment design or operation. A list…