Police have completed their investigation into Slovenia's deadliest industrial disaster, the May 2022 explosion at the Melamin chemical plant in Kočevje. The company's CEO Srečko Štefanič is unofficially one of the four persons facing charges along with one legal entity.

The investigation found that the blast and subsequent fire at Melamin were caused by a chemical substance brought into the factory by a truck that had been pumped into a wrong tank. This caused two incompatible compounds to come into contact.

Seven people were killed as a result, including two Bosnian citizens and one Macedonian. Five of them died on the spot and two at the hospital a few days later. 32 people who were in the immediate vicinity suffered minor injuries. Most of them sustained burns or were admitted for medical treatment due to carbon monoxide inhalation.

The accident caused major damage to various buildings and vehicles both inside the factory compound and in the surrounding area. According to an unofficial estimate cited by the police, the total damage to property exceeds €37 million.

The investigation identified a number of irregularities under the occupational health and safety act, as well as "causal links between the failure to comply with the duty to ensure the health and safety of workers and the resulting consequences".

Presenting the conclusions to the public on 22 February, Valter Zrinski of the Ljubljana Police Department said the key accusation against those responsible is failure to follow all security protocols.

Police filed criminal charges against four individuals and one legal entity. The Melamin CEO, who is unofficially among them, was not available for comment.

Endangering safety at work carries between one and eight years in prison and causing general endangerment a prison sentence of up to five years.

The STA has obtained a criminal report filed by the Labour Inspectorate against Melamin in September last year. It is not clear to what extent the report overlaps the police's findings, but the inspectorate accused four individuals of responsibility - CEO Štefanič, the head of the chemical industry business unit at Melamin Damjan Murn and two more employees.

Among other things the officials are accused of failures that eventually prevented a worker from pumping a wrong substance into a tank of epichlorohydrin, a volatile substance.

The inspectorate reported that on the day of the accident the company Transport Vodenik brought in the raw material diethylenetriamine in a shipping container. The driver took the paperwork to a Melamine employee and then drove to the epichlorohydrin unloading station instead of to the diethylenetriamine unloading station.

A Melamine employee took a sample of the substance brought in, marked it as a sample of epichlorohydrin and sent it to the quality testing department. Without waiting for the results, diethylenetriamine began to be pumped into the epichlorohydrin tank, which caused the blast.

A special adapter needed for pumping epichlorohydrin for safety reasons was used in the process, but the inspectorate said Melamin had no safety protocol in place as regards the use of the adapter, nor had additional oversight of the pumping of hazardous substances been secured. A single employee managed the process, although sufficient staff was available.

Melamin responded by saying it had not been notified officially about the conclusion of the investigation and could not comment. The company added that it had been working constructively with all the relevant institutions from the very outset, providing all the necessary documentation and information.

Kočevje Mayor Vladimir Prebilič said that despite assurances to the contrary, not everything was by the book at Melamin. He believes the company should move to another location.