Federal Police experts found strong evidence that a series of makeshift connections in the electrical wiring caused the fire that swept through the National Museum eight months ago, keeping its doors closed ever since.
The "most plausible primary cause" of the fire has been identified: air conditioning unit C, one of three units cooling the ground-floor auditorium, malfunctioned on the night of September 2, 2018, directly below the room housing the 13-meter-long fossil of the Maxakalisaurus topai, a dinosaur that inhabited South America 80 million years ago.
A report presented last week at the Federal Police Headquarters in Rio points to signs that the electrical installations did not follow "manufacturer recommendations" in at least two instances, according to forensic expert Marco Antônio Zatta.
Causes of the fire
Each of the three air conditioning units in the auditorium should have had its own circuit breaker. Instead, investigators found: "Rather than connecting directly to a main panel, a parallel connection was made. There should have been a circuit breaker for each unit. There was only one for all three." The Federal Police had already received reports of this, and the evidence was found, Zatta stated. "Obviously this is not normal. It did not follow the manufacturer's recommendation."
The unit that short-circuited was the only one receiving power at the time. "That does not mean it was turned on, but rather on standby, waiting for a command from the remote control."
The second cause identified is that there was no electrical grounding there. According to the expert, this may have contributed to worsening the malfunction. It is like "the story of the third prong on a plug; there is a reason for it to be there," he illustrated. "In the event of an electrical fault, it drains through the grounding system."
Aggravating Factor: Lack of Equipment
Zatta also pointed to the lack of equipment that could have extinguished the flames more quickly, in addition to deficiencies in the fire suppression system. While there were fire extinguishers inside the room where the fire started—all within their expiration dates—and a nearby hydrant, the Federal Police team did not find, for example, sprinklers, a fully functioning fire alarm, or fire doors.
The Federal Police team found neither wall-mounted fire hydrants with hoses nor working alarms. An extinguisher "would never have been enough to fight a fire of that scale," he said. Furthermore, without fire doors, "the spread [of the fire] was made easier."
Based on photos taken before the blaze, they also found no signs in several rooms indicating what to do in case of fire, such as which emergency exit to use. Had the museum been open, the tragedy could have been even greater.
No Intentional Act
The Federal Police found no evidence of an intentional act triggering the malfunction that ultimately destroyed the largest natural history and anthropological museum in Latin America, and also the oldest in Brazil, now 201 years old. King João VI founded it in 1818 at a different address, naming it the Royal Museum. The collection is currently housed in a palace that served as the residence of the royal family from 1808 to 1889, located in Quinta da Boa Vista, in the São Cristóvão neighborhood (in Rio's North Zone).
Arson typically leaves traces, such as the use of chemical accelerants. Forensic experts found no such evidence. They also ruled out the hypothesis that a sky lantern or a lightning strike caused the flames that engulfed thousands of the more than 20 million items stored there.
Initially, almost everything was feared lost, but valuable items from the collection were recovered during searches through the rubble that spanned months. This was the case with the skull of Luzia, the oldest human fossil discovered in Brazil and one of the oldest in the Americas, dating back approximately 12,000 years.
Leading the investigation, Federal Police Chief Paulo Teles recalled the challenges faced by his team, starting with the sheer size of the space: 13,000 square meters across its three floors.
According to Teles, "the most important question—whether someone acted with intent or negligence—" will not be answered just yet. The Federal Police, in partnership with the Federal Court of Accounts (TCU), will "reach a conclusion at the end of the investigation." He did not specify when that would be.
Via Haus
This article was written by HAUS. The translation is powered by AI.
