An investigation by the  Fire Department establishes responsibilities in the explosion in the PH Costa Mare in Don Bosco, on May 31, 2019, states that the explosion was the result of gas escaping through a valve that connected to a clothes dryer, in the apartment's laundry room.

"The responsibility of the person who opened or restored the gas to apartment 07-22 without first verifying that all the valves were closed is clear...", the document reads.

An electrical technician connected the gas service following the instructions of the horizontal property administrator, On the day of the explosion, Miguel Muñoz, the owner, requested the re-establishment of the gas and electricity service. The administrator agreed that he would do it in the afternoon, before the arrival of the family, which was scheduled for the night.

He issued instructions to an electrician, who did not have a license to accredit him for the task, to open the stopcock and restore the gas supply.

The technician proceeded to follow the instructions and opened the stopcock located on the stairs of the building but, according to the protocol for the use of liquefied gas, in the connection process, in a new pipeline, the entire system must be inspected so that there are no open terminals and all the valves are closed and covered.

As a preventive measure, it also establishes that after the gas has been connected to a new system or has been restarted after a service interruption, the tightness of the piping must be checked and where a leak appears, the supply must be cut off.

But, the electrician assured that he did not have access or authorization to enter the apartment. For nine hours, the gas escaped from a valve in the laundry center that was kept open because a tenant had left it open after unplugging her clothes dryer.

During that time, the gas bubbles traveled through different ducts and spaces and mixed with oxygen. According to the report, it first accumulated in the laundry room and, later due to saturation, it leaked into the bedroom and other areas of the apartment saturated with gas, it leaked through the cracks in the doors Neighbors felt a "smell of a dead animal", of "garbage" and reported the anomaly to the administration that underestimated the risks and believed that it was sewage, At night, the Muñoz Lima family arrived in Costa Mare to live in the apartment.

In 9 hours, the gas bubbles traveled through different ducts and spaces and mixed with oxygen, causing a powerful explosion that destroyed practically all the interior and exterior walls of the apartment and caused the death of a 10-month-old baby and caused serious injuries to another child under the age of 5 and to the 35-year-old mother of both children The first report of the explosion occurred at 10:13 p.m. just as the family entered the apartment.“The detonation traveled at a sonic velocity in the air with pressure from saturation,” says the report adding that “the expansion and impact waves increased their power in zone one as it moved away from the point of ignition”. The administration of the residence disclaimed any responsibility, arguing that it was only responsible for the maintenance of the common areas.

Judge recusal
There are three defendants for the explosion: the PH managing company, the administrator, and the maintenance assistant, for culpable homicide and personal injury.

The oral trial began on March 6, 2023, but was suspended after a challenge filed by the homicide prosecutor's office against Judge Leila Terán because it was known that the firm that represents the defendants acts as a defense for a relative of hers.