CHEMICAL PLANTS ACCIDENT ONE YEAR ON

Iqoxe explosion: Court reveals material and safety deficits

Two audits by the chemical industry had already warned of errors in the plant that needed to be corrected

Esther C. Mirall
5 min
01. Bombers remullant la planta després de l’explosió. 02. Estat en què va quedar  la fàbrica.

TarragonaWhat chain of events led to the deadly explosion at the Iqoxe chemical plant on January 14, 2020 at La Canonja? With a balance of three dead, eight injured, losses in the millions, lack of institutional coordination and alarm among the population, the judicial investigation is still open. The provisional conclusions point to crimes of serious negligence resulting in death, injury and damage and as well as infringements of workers' rights.

ARA has had access to part of the court case's summary, which includes statements from workers and two audits by Dow and Repsol at the Iqoxe facilities that show a lack of personnel and deficiencies in security. There is also a communication from Civil Protection which refused the company's Self-Protection Plan in 2013, 2016, 2017, 2018 and 2019 for not having passed the technical reports, although Iqoxe maintains that, despite the fact that it was not approved by the regulator, the company has always had a Self-Protection Plan in place.

Until now, two reports on the technical causes of the explosion had been made public, one by the Chemical Institute of Sarrià, commissioned by Iqoxe, and the other by the consultancy firm DNV, commissioned by the Government of Catalonia. The crossed data help to better understand how the Uno3100 unit, inaugurated in March 2017 with state-of-the-art safety, came to be operated. The control room was placed in an old building which collapsed killing the floor manager and the foreman. The collapse also meant all the control room data was lost.

The case summary records the testimony of workers who claim that the unit oscillated too much in temperature and pressure when it was making MPEG. Therefore, "the workers had to build one or two by-passes for the reaction to take place" and then closed them "if they remembered". A by-pass, according to experts consulted by the ARA, is like a manual shortcut to skip steps in an automated process. An Iqoxe spokesman confirmed to ARA that at 3 p.m. on the day of the explosion a by-pass had been made at the time of loading the ethylene oxide and that the by-pass had been closed afterwards, and noted that the reaction between the products had taken place. In other words, the MPEG-500 had already been manufactured.

The investigation also reconstructs how a company with no experience in manufacturing this product saw an opportunity to open markets and expand. "It will silence production complaints," the plant manager wrote down in a notebook in August 2018. The first customer interested was a Swiss company, and the second was a multinational working in the Tarragona chemical industry. From internal communications, it is clear that the engineers were looking for a formula for MPEG-500 suitable for both clients, and if it could be for more, so much the better. Finally, they started manufacturing the new product in June 2019.

A chain of anomalies

January 14 could have been a normal day at the plant, but a series of anomalies coincided. The first is that six 25-tonne batches were manufactured, but the seventh batch had to be 20.5 tonnes at the request of the client. This implied changes in the recipe, but the server was already causing problems and there were issues loading. This is what is stated in the work orders of the 14th. This document states what has to be fixed, where and by whom, and that day the unit concentrated 13 orders. Eleven were not urgent, but two had to be corrected "immediately". That would be one problem. Then, there was the P3132 pump, which, according to the summary, was often damaged. That day, however, it was pump P3152 that was causing trouble. But because of a human mistake someone typed 3132 when he put through the work order. This confusion is irrelevant because neither pump was critically unsafe, according to the IQS report. However, the detail helps to draw the work environment, which still adds up to two more anomalies: a worker arrived twenty minutes late - he was covered by a colleague - and the supervisor left half an hour early because he had to go to the dentist.

According to the summary, the normal day-to-day life was already one of pressure, with operators overwhelmed and "taking advantage of the start of the reaction to eat or go to the bathroom". The derivatives staff also suffered from "quantitative demands, work rhythm, emotional demands and double presence", according to a report on psychosocial factors made by the company itself. All this pressure, one worker said, led to accidents at work. In fact, from 2014 onwards, the mutual insurance company increased assistance by 800% for all staff.

An Iqoxe spokesperson maintains that the staff is sufficient and that it is above the figures set by regulations. As for the negative testimonies, they are attributed to possible workers who were dismissed in December 2019 and to leading questions by the judicial police.

The summary records these dismissals, which led to a 24-hour strike in protest. That December, six workers were dismissed, most of them from the derivatives plant, which implied one worker less per shift. A quality audit carried out by Repsol in Iqoxe in November 2018 already warned: "In all the interviews carried out by the different departments there is a clear lack of resources, both material and especially human". And it stated: "Often the comments are 'I don't have time', 'there are not enough staff'".

Another security audit, conducted by Dow in mid-January 2019, concluded that "actions are not followed up and are not properly validated", and noted that "worst-case scenarios in the infrastructure could not be assessed". The company claims that these two audits did not focus on the derivatives plant where the accident occurred.

Meanwhile, there are still many gaps in understanding the technical causes of the explosion, which was so powerful that a piece of the bottom of the reactor, weighing 800 kilos, went off like a missile, flew 2,400 metres until it hit a block of flats in the Torreforta neighbourhood and killed a neighbour who was at home. The Sarrià Chemical Institute assumes that ethylene oxide cannot cause such a violent reaction and therefore points out that the explosion took place when the final product had already been produced and thermally decomposed until it exploded. This conclusion, which the company takes for granted, is unprecedented on record, so the report concludes that it was "a sudden, unexpected and unpredictable chemical reaction as yet unknown". DNV consultants, on the other hand, point out that ethylene oxide could be the cause of the incident. It refers to a similar accident in Zwijndrecht, Belgium, where, as in the case of Iqoxe, a fireball was also generated with fires and significant damage due to shrapnel and the blast wave. DNV notes, however, that it has suffered from many information gaps and recommends a third report.

Experts consulted by ARA agree on the need for this third report. Thus, Professor Emeritus of Chemical Engineering Francesc Castells has compared the two studies. In his opinion, the two teams should pool their data in order "to have a more complete picture of the accident and to be able to better settle responsibilities". Castells recalls that, in industrial safety, "no accident is totally unpredictable".

For its part, Iqoxe maintains that it has provided all the data requested and assures that it would look very favourably on a third study, which could be requested by the judge as an independent expert.

stats