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Is the Equipment Safely Isolated and Ready for Human Intervention?

Andy Bartlett

On this inaugural episode of The Future of ESG Risk Management SpheraNOW podcast series, Alex Studd, a product marketing manager at Sphera, is joined by Sphera solution engineers Andy Bartlett and Abhilash Menon to discuss equipment isolation safety.

The following transcript was edited for style, length and clarity.

Alex Studd: 

Welcome to the SpheraNOW ESG podcast, a program focused on safety, sustainability and productivity topics. I’m Alex Studd, one of Sphera’s product marketers with a focus on operational risk management.  

Today we start a new series called “The Future of ESG Risk Management.” This episode features Andy Bartlett from the famous Andy’s Almanac. Andy is a solution engineer with over 40 years of process safety management (PSM) experience. And today we’re joined by a special guest, Abhilash Menon, another solution engineer based in the United Kingdom. Welcome to the show, gentlemen. 

Andy Bartlett: 

Hi everyone. It’s good to be back with this new series, and hopefully we can get some nice tidbits for all the people to enjoy. 

Abhilash Menon: 

Happy to be part of this series and be the first to be invited. I have followed all of Andy’s Almanac and I’m glad to share some of my experience here as well. 

Alex Studd: 

Well, I’m excited to have you both here. This episode is called, “Is the Equipment Safely Isolated and Is It Ready for Human Intervention?” Andy, what are your first thoughts to hearing, “Is it safely isolated?” 

Andy Bartlett: 

My reply would be, “Is it? How do I know?” According to the Health and Safety Executive (HSE), every year, a huge number of workers are killed in workplace accidents which could have been prevented. It’s estimated that in the U.K., 120 fatalities and around 50,000 injuries are prevented directly due to the correct use of LOTO (lockout/tagout) in hazardous energy every year. Yet, lockout/tagout still seems to be only used to a fraction of the levels it should be. 

In a study conducted by the U.S. United Auto Workers union, 20% of the fatalities that occurred among their members were attributed to inadequate lockout/tagout and hazardous energy control procedures. From the U.S. Chemical Safety Board (CSB), a worrying statistic, 37% of incidents the CSB investigated occurred prior to, during or immediately following maintenance work, which is the prime period when isolation and deisolation is required. Safe Work Australia publishes statistics, but they do not have a category for isolation. However, it does have a category for being trapped by moving machine at 7% and other mechanisms at 13%. Again, this is due to isolation not being done properly. 

Alex Studd: 

Andy, I know you saw a lot in your career. How have you been involved in performing isolations? 

Andy Bartlett: 

Well, during my career I’ve been fortunate not to be injured due to LOTO isolation failures. In my time in operations, I attached and removed hundreds of locks. We had limited visibility at that time—only a lock board, logbook and spectacle blind list.  

As I issued permits and went out on the work site in my Cushman work cart to perform joint site inspections and to ensure the permit receivers had installed their locks and tags in the correct places, I had a hook on the dash for my key ring. It was the size of a soccer ball and contained all the keys, which were numbered for the locks at our lockout system.  

Human error incidents with forgotten locks not removed did happen. We kept the master key and a bolt cutter in the shift manager’s vehicle, so it was logged when and what it was used for. Also, the importance of color-coding locks for ease in identifying by trade or contractor company cannot be underestimated. 

Alex Studd: 

Andy, I know this isn’t a fun question, did you experience or see a colleague experience an accident that was due to improper isolations? 

Andy Bartlett: 

In my time in operations, I’ve been a witness to several isolation failures. I wish I hadn’t. One of which was in the plant next to ours. There was a big explosion while it was starting up after a shutdown. This was caused by a forgotten lock on a naphtha spheroid valve outlet line. The operations leader and the unit engineer were killed by the explosion, as they were on the way up the tank to remove the locks and open the valves.  

I was assigned as part of the recovery team to manage the resulting fire. Another incident I was called to take part in as a member of an investigation team involved a machinist who was assigned to remove a coupling on a pump. As he released the last bolt, the pump spun in reverse, wrapping his arm around the shaft. The check start-up process bypass had been left open—it had been missed from the isolation process. It was still open, allowing product to flow into the pump impeller and start it moving. This was a LOTO failure. 

Alex Studd: 

What about you Abhilash? Have you heard stories of a business that had a failure or an issue due to improper isolation? 

Abhilash Menon: 

Prior to my time at Sphera, I was a project and a site manager for a large global engineering, procurement and construction (EPC) and manufacturing company. I worked in locations which were managed by contractors and sometimes with workers who were not trained to the highest level. And when I say trained, I’m talking specifically about operational safety training.  

I can think of two specific instances where this kind of issue in terms of training caused incidents that relate to improper lockout/tagout communication around isolation. The first one was a case of simultaneous operations in place with an isolation plan. There was a person who was supposed to be welding on a large pressure vessel while this was being fabricated. He was using a ladder and went on top with some scaffolding. 

Alongside, there was work going on for maintenance of an overhead crane. The procedure for the crane electrical isolation was not clearly documented and hence not followed correctly, which meant that the person working on the pressure vessel didn’t know that the crane movement was about to be tested. And eventually the crane bump test caused the hook of the crane to hit the vessel and the welder that was working on it fell down. Fortunately, the worker only had a fall and did not suffer major injuries.  

The second instance I was personally involved in occurred when I was a young graduate engineer coming straight out of university. We were in the process of testing some cementing units for oil wells. In this particular process, the high-pressure cementing pumps were supposed to be tested. And to do this, there are a series of valves that need to be isolated and then run the pump with one of the valves slightly open. 

Regrettably, I was not trained properly, and the person operating the pump whose job it was to increase the pump pressure also did not communicate the process to the team correctly. Remember this is a case going back almost 18 years for me and all the processes at that time were on paper. The operator then increased the pump pressure without signaling the same, and due to the improper isolation of one of the valves, the pump that we were testing broke. 

There was huge financial damage. While it broke, two-inch nuts sitting on top of those pumps flew past my head about six inches away like bullets. I still remember that quite vividly. I count myself very fortunate that I’m still here recounting the story and not having any damage from that day. The only damage that day was on the pump. 

Alex Studd: 

Wow, that’s a pretty scary story. Thanks for sharing that, Abhilash. Let’s talk about failure modes and lockout/tagout in particular. Andy?

Andy Bartlett: 

There’s a lot of information on the web on LOTO accidents, and I would like to give you my take on some of the most common causes: Failure to de-energize, failure to double check, failure to drain residues, training being less than adequate, lack of equipment-specific lockout procedures and use of duplicate master keys and shared locks—all of these have potential for accidents. Looking at failure to de-energize, I would class this as a human error in the routine violations category. Looking at the number of incidents worldwide, this is more common than we would like to think. 

I know of an incident which resulted in a fatality due to not checking the isolation was on the correct equipment, which was being worked on. The equipment was a fin fan cooler in a large bank. Each fan had to have its safety cage removed and entered to check the drive belt tension. The access point to the fan was up several stairways. The isolators were at ground level, and again, the human error of isolating the wrong fan occurred. The fan being worked on started automatically as part of the operating process and fatally injured the worker inside the shroud. 

Failure to double check the settings by the worker entering the fin fan shroud also played a part in this incident. Another one is failure to drain residues. An important part of the mechanical isolation process is to drain residues and flush with inert materials before attempting to open drains or vents and break flange joints.  

I was involved in investigating a flash fire and burns to the fitter who was breaking the flange at the time. Residual pyrophoric iron sulfide ignited on exposure to air—the short section of line had not been flushed with the inert materials before issuing the permit to work. 

Lack of training is illustrated by accepting someone else’s word that it’s safely isolated without making the responsible party come to the location and verify the isolation is corrector that they’re working on the correct piece of equipment. Permitted work was issued on furnace A, which was isolated and out of service for repairs. The contractor receiving the permit went to work on furnace B, which was in service. When opening the flange, fuel gas escaped and ignited from the furnace burner, causing burns to the contractor. An emergency shut down was required to stop the fire. Again, this was a failure to double-check the settings by the worker. 

Abhilash Menon: 

And Andy, there is also a lack of equipment-specific lockout procedures. Only recently has technology been available to store and give ease of access to equipment-specific isolation plans. These would’ve been deployed over time and previously stored in folders or document recovery systems.  

Now mobile technology allows access to these in a few clicks. I remember the days when our isolation plans were kept in waterproof notebooks. Also, I remember the use of duplicate master keys or shared locks. It was common in the past to have duplicates or master keys. However, this is not recommended today. Most companies have introduced the lockbox methodology. Locks can be counted out to match the plan beforehand and the keys kept in the lockbox during the isolation under the control of the asset owner. Again, technology can be used to track these lockbox details clearly now. 

Alex Studd: 

Even though we’ve established a lot of processes, accidents still happen as a failure to follow them properly. What procedures aren’t being followed, and why is it so difficult to follow them, Abhilash? 

Abhilash Menon: 

There is no doubt that isolation practice and processes can be improved by supplying the right tools while also improving isolation discipline and ensuring adherence to policies from beginning to the end of the entire life cycle, the entire process. However, this doesn’t happen on its own. An effective energy isolation program should identify all hazardous energy sources including electrical, mechanical and hydraulic.  

There are a lot of things that need to go in there. You need to identify all types of energy isolating devices, such as valves or electrical boxes. You’ve got to include proper labeling using standard formatting that clearly identifies the equipment, the energy isolation points, methods, as well as disclaimers indicating when it is to be operated or when it is not to be operated.  

As part of the process, it is important to develop a clear and comprehensive isolation point register as well. Isolation plans should be developed for each type of equipment, such as pressure vessels, fire heaters, pumps and compressors. There are a lot of things that go in in terms of processes as well as systems that need to be put in place for things to be safe. 

Andy Bartlett: 

When I was in operations, we included the blind list in the equipment standard operating procedure (SOP). Blinds and/or slip plates or spades—called different things around the world—provide positive isolation. They are usually installed in all lines which leave or enter a vessel, preferably at the first flange off the vessel, in order to positively eliminate leaking of materials entering the vessel when air is introduced. During commissioning and startup, these blinds and/or slip plates are removed. 

The sequence of blinding and unblinding must be carefully planned prior to start up or shut down. A blind list of all the blinds to be installed and removed should be made. Blinds should be properly tagged, and the tag ID should be reflected on a checklist 

When the above steps are followed, the potential for error is significantly reduced. Another major cause of fatalities worldwide is confined space entry. Here, isolation is paramount to the safety of the individuals working inside the confined space. For this activity, the isolation plan must be current and approved before use. I have reviewed several web-published energy isolation work processes from various companies. They all required the same disciplines, which can be shortened to lock, tag and try. 

Alex Studd: 

I think it’s fair to say that there’s been an emergence of technology to assist with successful isolations. Abhilash, you mentioned your personal story 18 years ago and how you were still working on paper and how things may have been different had it been digitized. What specific technologies have you been seeing in the industry that businesses have been leveraging in recent years? 

Abhilash Menon: 

Today with electronic lockout/tagout software, companies can better plan and manage the safe execution of isolation activities, such as removing hydrocarbon or other hazardous energy from pipes, tanks, vessels and mechanical equipment. Work can be done safely on a part or section of the plant and communicated to the teams that are working on the plant. Isolation plans can be prepared electronically beforehand and are visible to the whole team. Isolations can be approved ahead of the requirements and time period, so it’s not all done last minute. 

You can have templates for lockout/tagout plans that can be used repeatedly with a click of a button. Any lessons learned—positive or negative—can now be stored and linked with these so you do not lose key corporate knowledge, or, as people call it, “tribal knowledge,” within the organization. Technology can help to keep track of the real-time status of each isolation point so it can help monitor the integrity of those critical valves that need to be isolated or monitored along with clear auditability of the work authorization. 

You know who’s done what out in the field as well as at what time. There are also a lot of breakthroughs in terms of how these electronic lockout/tagouts are put in place and are implemented. You can now use interactive piping and instrumentation diagram (P&ID) software while leveraging existing PDF versions of the P&ID. Keep it simple and mark up the electronic document with actions, rules and isolation points. The breakthrough in using these interactive P&ID files has ensured engineering, maintenance and operations silos can be broken down and organizations can effectively collaborate on isolation planning. 

Lastly, innovations in using mobile devices to scan QR codes for the isolation tags and field are super cool. Geographic information system (GIS) tracking technology can help to ensure that a user is in the right place and working on the right equipment. Mobile technology can ensure that they conduct the isolation in the right way. And this eliminates errors in the process. Just like those examples that Andy mentioned, you wouldn’t be in the wrong place doing the isolation for the wrong equipment. 

Andy Bartlett: 

And these technologies are super powerful because this helps teams manage isolation procedures when preparing the plan for safe work, electronically planning parent and child isolation plans, testing and the return of normal operations. In terms of isolation policy to practice, different organizations have made tweaks to the standard isolation process, and with the technology available today, enhancements can be made to the isolation software solution to incorporate this segregation of duties. 

Alex Studd: 

Andy, to wrap up, I’m curious what you would say you’ve learned throughout your career on isolations. 

Andy Bartlett: 

After leaving school, I had a few jobs before I was able to get a job in the chemical industry, which was a very well-paying industry in my area. On my first shift, I learned all about isolation. I had started work as a cleaner. The company mantra was, “when you know how to clean everything, we’ll teach you how to operate it.” On this first shift, I had to make a confined space entry into a vinyl chloride reactor to clean it. I had to take the resin from the sides and pipe exits. The reactor had a stirrer, or agitator driven by an electric motor.  

The supervisor showed me—as I had to witness it by law—how the fuses were taken from the breaker cubicle and locked in a box in his office, with him having a key on his person. The work permit contained the blind lists, all three of them. I witnessed the oxygen test and the vinyl chloride residual before entry. As I said in the beginning, I’ve made and witnessed hundreds of isolations. It’s an everyday occurrence in every industry and must be performed correctly to prevent harm to the individuals working in the facility. 

Abhilash Menon: 

Everyone is a technophile these days. Why not translate that personal love for technology to the operational safety world? Today, by employing the available technology, a big improvement can be achieved in isolation management and operational safety. The right technology solution definitely ensures that the equipment isolation is safe and ready for human intervention. 

Alex Studd: 

Well, thank you both so much for your insights and perspective on this. Thank you for joining this new series, which is part of the SpheraNOW ESG podcast. Andy, we’re excited to continue this series, and Abhilash, I’m sure we’ll see you back. 

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