26/02/2026
A risk engineer has to review many aspects during a risk inspection visit. Elements such as location, construction type, distances between units, tanks, buildings etc., facilities maintenance, physical safety, and the fire protection measures in place at the plant. All of this forms part of the evaluation that the engineer will conduct at the plant to subsequently include in their technical model and generate a technical score for the installation.
Within all these aspects, two of them are key: process safety management (PSM) and inspection.
In these types of plants, it must be taken into account that most of the fluids that pass through the pipes are hydrocarbons, therefore, fuels, which means that the number one concern must be that they don’t leak from the pipes, containers, or reactors where they are being stored.
This is where these two aspects come into play. First off, we have inspection of the installations (pipes, tanks, reactors, towers, columns, etc.), so that we ensure there are no hydrocarbon leaks. Next up is process safety management within the parameters indicated in the operational model established in the project for that installation, so that situations leading to runaways don’t occur (runaway reactions in petrochemical plants are critical safety events where an exothermic reaction loses temperature control, causing a rapid, self-sustaining rise in temperature and pressure that can lead to explosions, fires, and toxic release), or subjecting the installations to temperature and pressure conditions in excess of commissioned limits that will ultimately lead to hydrocarbon leaks, explosions, pressurization, etc.
There follows a detailed overview of each of these two key points, along with practical examples from my own experience.
PROCESS SAFETY MANAGEMENT (PSM)
Aspects such as MOC (Management of Change), management of safety bypasses, work permits + LOTO (lockout/tagout), HAZOP (Hazard and Operability Study) or SIL (Safety Integrity Level) studies, PID controllers (Proportional-Integral-Derivative), operational and emergency procedures, alarm management and rationalization, incident investigation, safety audits, and PSSR (Pre Start-Up Safety Review) are key aspects of process safety in this type of plant.
Here are some examples of related violations I’ve encountered at various installations in my professional life…
- It’s common at times to observe, especially in summer, water hoses lying on heat exchangers, which don’t provide the designed capacity (due to fouling), and for this reason, they are externally cooled with water. This change should be managed via the MOC procedure and many times it is not. Situations where this water falls from the outside of the exchanger to lower areas where there are LPG (Liquefied Petroleum Gas) pumps or other hydrocarbon pipelines are common, and therefore, this water can cause corrosion over time, leading to the leakage of hydrocarbons, which is something we absolutely do not want. That’s why proper change management will ensure that these elements are reviewed or inspected more often so that a leak doesn’t occur.Here’s another management of change example that I observed recently while visiting a plant overseas. While reviewing an accident at this plant, it was discovered that, after several modifications, the corresponding MOCs had not been made for this part of the installation, which involve conducting a risk assessment when any changes are made. In this case, this accident occurred because of that failure to implement the MOCs. At the facility itself, they acknowledged that in the last seven or eight years, MOC management was deficient or not done correctly. Doing simple math, at 100 annual MOCs, there are about 700 or 800 MOCs not done correctly and, therefore, 700 or 800 potentially dangerous situations that could lead to incidents or accidents like the one that had recently occurred. That’s why we recommend that both the broker and client review all of these potentially dangerous scenarios.
- What is PSSR (Pre Start-Up Safety Review)? Broadly speaking, PSSR is the review of all safety elements of the facility just before startup, whether because the plant has stopped for maintenance, or an unplanned shutdown, etc. There are many occasions when, especially after maintenance shutdowns, not all safety aspects of the facility are reviewed (due to the rush to get into production mode). Many accidents arise from this, which is why it’s important for the engineer to ask about this aspect during the visit and understand how the plant is managed in this type of situation.
- Management and rationalization of alarms. When you visit a facility of this type, during a tour of the control room, it’s common to continuously hear beeping alarms everywhere. Many times, the operators mute them because of the annoying sound. Well, our interest as insurance engineers is that the control operators have a reasonable level of alarms (according to EEMUA code 191, six alarms per operator per hour), so that they can safely address all the situations of the day-to-day operations of the plant. If they have a very high number of alarms (sometimes we are talking about hundreds of alarms per operator per hour) it’s very likely that an important alarm will be missed, creating a potentially risky situation for the plant.
- Management of safety elements. In countless cases, I find plants where safety elements are bypassed and there is no management of that situation. One example was a switch indicating a very high level on a tank that was bypassed for maintenance. If proper attention isn’t paid, it’s very likely that, in a situation of stress, the control operator will forget that this element had been bypassed and a tank full of hydrocarbons will overflow.
- Work permits + LOTO. Countless accidents arise due to mismanaging this aspect. For example, think of a pump with LPG inside that needs to be taken out for maintenance. That pump requires an isolated pump to be opened safely so that there are no leaks of LPG. Unfortunately, there are numerous cases where this isolation isn’t done correctly or in full compliance. Leaks and subsequent explosions are common where well-implemented procedures are lacking.
- Management of installation plans (PIDs, piping and instrumentation diagrams). On numerous occasions, we find in the control room copies of outdated plans that haven’t been updated. Despite the work involved, it’s important to keep them updated so that the field operator can refer to the PIDs to verify the situation with a pipeline in their plant in an emergency situation. If the PID isn’t updated to its latest version, it may not block all the lines to carry out its action, it might overlook some, and as a result, a hydrocarbon leak could occur. This aspect is also key when managing the LOTOs or isolations. If the PIDs are not properly updated, it’s possible that some lines will remain unisolated, ultimately causing a leak. Many times, the plants justify things by saying that the operators are very experienced and know the plant perfectly, but this is exactly what we want to avoid, and for this reason, there must be procedures for everything in place so that we don’t rely solely on the operator’s memory.
Let’s now take a closer look at the second aspect that I mentioned, namely, inspection.
INSPECTION
This involves periodically inspecting the pipes, equipment, towers, reactors, tanks, etc., with the intention of ensuring there are no leaks. It’s as simple as that.
Before visiting the facility, the risk engineer should, at a minimum, have a general idea of the degradation mechanisms (High Temperature Hydrogen Attack (HTHA), Corrosion by organic chloride, Corrosion by SH2, etc.), possible in the different process units. Having this information to hand means that checks can be done to see if they were taken into account at the time of planning the inspections. This point is sometimes difficult and is acquired through experience, training, etc.
Let’s analyze some risky situations that I’ve encountered during inspections in recent years.
- A relevant aspect is who is responsible for the Inspection Department within the plant. It’s common for it to be supervised by the maintenance manager. This is important because often, production is prioritized over safety. It’s very important to suggest to the plant owners that the Inspection Department should report directly to senior management, so that, with all the available data, they can decide whether to stop a plant for inspection or not, and not other personnel lower down the command chain who sometimes delay important reviews that need to be done because of budget constraints.
- It’s common to come across inspection departments that don’t have sufficient training who then place the burden on the shift contractors. This is also not correct because, after all, the owner of the facility must know how to interpret the results of the inspections carried out by the contractors and make decisions accordingly.
- It’s also common to find that the Inspection department does its work well but doesn’t analyze the data obtained. For example, during a visit to a facility, data showing a 25 or 30% failure rate in the pre-pop tests of the PSVs was presented. The plant staff were perfectly calm, commenting that all the failing PSVs would be replaced. Rates of this level are frightening, with a typical failure rate being in the region of 6 to 8% at most for this type of facility. Management should conduct a root cause study to discover why the PSV failure rate is so high, so that they can correct the problem at the source.
- Another interesting aspect to discuss is the inspection check, which is the calculation of the remaining life of the pipes. Many times, the baselines used are taken are theoretical and not based on real data during the plant startup, leading to erroneous conclusions about how often to inspect a given line. It’s important to have accurate data on line thicknesses before startup so as to have the most reliable information at the outset.
- At other times we find that, although in the plant they take many inspection procedures into account, they sometimes forget about others. It’s vital to review aspects such as PMI (Positive Material Identification), CUI (Corrosion Under Insulation), CUF (Corrosion Under Fireproofing), and dead-legs (components of a piping system that normally have minimal or zero flow). Failure to do so has caused numerous accidents over time and that’s why having a department with experienced personnel and well-trained staff is essential.
- Another important aspect is overdue inspections. Risk engineers request that plants follow a procedure to manage them, which involves not forgetting or excessively postponing their revision, which in turn aggravates the risk of an accident occurring at the facility.
In conclusion, I hope I’ve been able to shed some light on the key aspects to consider when conducting an inspection of a refinery or petrochemical terminal.
David López Martinez de Salinas
Senior Risk Engineer at Mapfre Global Risks
