Multiple system failure is the root cause of large property damage losses in the energy sector, according to a report published Wednesday by brokerage Marsh L.L.C.

The global energy sector has sustained property damage losses of more than $34 billion since 1974, with seven of the largest 100 losses occurring since 2012, according to the report “The 100 Largest Losses.”

“Typically, none of the losses are the result of the failure of a single barrier or protection measure,” the report noted

Of the 20 largest losses over the last 40 years, eight occurred in the United States, three in Europe, and two in Brazil, the report says.

Large energy losses typically occur because of the failure of a number of systems such as hardware, management systems and emergency controls, or the failure of barriers within the process-safety management system for hydrocarbon assets, occurring at the same time, according to the report.

The biggest energy loss was the Piper Alpha North Sea rig explosion off the U.K. coast in 1988, which cost an estimated $1.81 billion inflated to 2013 values, according to the report.

The second-costliest energy loss was a vapor cloud explosion in Pasadena, Texas, in 1989 that cost an estimated $1.40 billion, the report noted.

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Since 2012, the largest losses have been a chemical plant explosion in Geismar, La., in June 2013 that cost $510 million, and flooding and fire at a refinery in La Plata, Argentina, in April 2013 that cost about $500 million, the report noted.

Andrew George, the London-based chairman of Marsh's global energy practice, said in a statement that the global energy sector has become increasingly sophisticated in its approach to risk management, “most notably in the deployment of new technologies and in emerging markets.”

But he noted that “continued risk minimization in the global energy sector depends on maintaining vigilance on new and developing threats, and forming strategies to prevent and mitigate their impact.”

The report can be found here.