Update 2: Gas incident due to faulty regulator - Liquigas

Enemalta said this afternoon that an explosion which blew a cooker hob off its mountings in an incident in a Birkirkara home last week was not caused by overfilling of a gas cyclinder, but a faulty regulator.

"Following investigations carried out on the gas cylinder and relative equipment which caused the incident at the Montanaro residence, it transpired that the regulator used by the Montanaros was found to be seriously damaged. Regulators normally need replacement after 5 years. Both regulators used were 12 years old, reducing their potential to withstand pressure from 20 to 6 bars," Enemalta said.

"When tested, the release from the cylinders was always in vapour form, clearly indicating that the cylinder was not overfilled. Should the cylinder have been overfilled, Liquified Petroleum Gas would have been released in liquid form.

"Gas cylinders are designed to withstand pressure of up to 65 bar and this particular cylinder was measured at 6 bar. Moreover, cylinders are filled by weight and not pressure, which is always constant and dependent only on temperature."

In a statement issued later in the day, Liquigas said that the pressure located in the two cylinders at GeorgeMontanaro’s house was not problematic. It was very usual for cylinder pressure to go up to five or six bar, due to solar heat and cylinders were produced to withstand a pressure of 65 bar.

Liquigas said that the cylinder in question was fully tested and certified abroad by Liquigas according to EU regulations, as part of an ongoing exercise initiated by Liquigas last year.

It said that the regulator used by Mr Montanaro was leaking. This leakage happened on the roof, in open air, not in the kitchen. He changed the regulator for another one used on a heater which according to him was not faulty and did not leak. Mrs Montanaro later tried to use the cooker when the incident occurred.

Liquigas said that the most feasible explanation was that a volume of gas passed through the first defective regulator, forced its way through the cooker valve and accumulated under the hob and then produced the incident.

In such case the cooker valve could either return to normal or suffer permanent damage. The use of a second regulator by Mr Montanaro could not have resolved the situation already created with the cooker valve, Liquigas said.

George and Marcelle Montanaro earlier this week filed a judicial protest against Enemalta and Liquigas, saying they had been told by Liquigas technicians that excessive pressure in their gas cylinder had caused the explosion in their Birkirkara home. A second gas cylinder was also found to have excessive pressure.

What was even more shocking, Mr Montanaro added, was that this was not the first time the technician had been sent to check out similar problems in other homes.

Enemalta said it had contacted Mr Montanaro and a meeting was arranged.

An internal investigation was held establish the cause of the incident.