Fire suppression equipment was switched off inside the switch room where the July 14 Belco blaze started.

That was the key finding of an independent inquiry into the fire that led to the Island-wide blackout.

The inquiry report was unveiled at a Press conference at Belco Holdings Ltd. headquarters yesterday.

The report said that while it might have been difficult to prevent the electrical fault that began the blaze from occurring, the damage could have been reduced if the fire protection systems had worked properly.

The fire plunged the Island into darkness on July 14, while parts of Hamilton were shut down for the next two days.

Belco chairman Michael Collier said power protection systems in the switch room failed that could and should have minimised the event.

?It is probable that the extent of the damage within the substation would have been significantly reduced if the fire suppression system had been active and able to extinguish the fire at the time of the initial smoke alarms,? said Dr. Dawn Miller, of independent agency EA Technologies.

?However, the capabilities of the fire suppression system are not known and, as energy was fed into the fault for a long period after the initial smoke alarms, it is possible that the fire may have reinitiated.?

She also said it had ?come to light that in this substation there was a historical fault with that protection which meant that it was out of commission?.

Belco CEO and president Garry Madeiros revealed the fire suppressers were disabled because they were indiscriminately going off and releasing life-threatening gas.

Bottles of carbon dioxide were piped throughout the room, which were designed to exclude oxygen from the fire scene to put the fire out.

The suppressers emitted gas by mistake and the people who worked in there feared for their life.

?That particular system was disabled because of a number of incidents where it went off and people were inside working,? he said.

?It became problematic for those doing maintenance work and they were disengaging. And consequently over time that disengagement became more of a routine than anything else.?

Belco?s chief operations officer Vincent Ingham said he did not see a manufacturer issue with the busbar fault. ?We do see a failure in our protection system,? Mr. Ingham said. ?Where this failure occurred was in the belly of the switch gear. We never expected that. Hence operating without the protection was a condition we could live with.?

The cost of the fire was estimated in July to be as high as $10 million.

But Belco said it was still incurring costs yesterday as it was installing a temporary switch room. It had yet to build a permanent replacement building for the one ruined by the fire.

Dr. Miller said it would be very difficult to prevent this fault from occurring. However, the damage could have been minimised if the protection had worked properly.

For a fault of this type there are two protection systems which could have operated to remove the fault from the network to stop the energy from coming into the fault, Dr. Miller said, but the first one did not work due to a historical fault that meant that it was out of commission, she said. ?The exact cause of the fault cannot be determined due to fire damage, but the most probable cause is a void or moisture ingress leading to partial discharge within the insulation and eventually flashover,? Dr. Miller said.

The second back-up protection system began to operate unfortunately not very well, and the faulty switch exploded with huge explosive force.

Within seconds, flames and acrid smoke filled the 93-foot-long substation but although flame and smoke sensors were activated, however, not the flame suppressers.

Large quantities of flammable insulating oil and bitumous compound kept the fire burning, she said. The flammable fuel inside the switch maintained the fire at temperatures over 660 degrees Celsius, she said.

Sixteen minutes later, a second major fault occurred which caused an overload on the generators. EA Consultant Colin Ross said busbar faults of this type were relatively rare and might happen only once every 20 years.

He said there are hundreds and thousands of this type of switch board around the world.

And it was difficult, if not impossible, to look inside the busbar and therefore non-maintainable. ?You actually have to break it open to see if it was broken,? Mr. Ross said. ?This particular switchboard was put together many, many years ago.?

He said there was a domino effect of three unrelated things, which unfortunately occurred at the same time. However he conceded it was preventable.

?There are always part of the system out of commission,? he said. ?You have to manage the situation to the best of your ability and I see nothing in Belco that is outside the norm.?

For example Belco was still waiting for a part that had not arrived by July 14, he said.

As a result, Mr. Madeiros said the switches to release the carbon dioxide gas to put out fires were now going to be made manual not automatic to prevent them being switched off.

Mr. Ingham admitted there was a ?less than satisfactory? maintenance schedule in the switch room.

Belco had always focussed its attention on the mechanical systems to make power, Mr. Ingham said, and needed now to spend more time and attention in the future to its secondary, protection systems, including suppression and detection systems. EA consultant Colin Ross said busbar switches were not generally used in the UK for power plants the size of Belco.

?It is a fairly rare installation it is normally only put in in situations possibly to do with an industrial consumer who might have a continuous process,? Mr. Ross said. ?The Board of Directors fully supports Belco?s executive and management team in the handling of the event and in their handling and commitment to identify areas where lessons from this event were learned and are now being implemented into strategy going forward,? Mr. Collier said.

Mr. Collier said the Board of Directors was pleased with the results of the inquiry and had unanimously decided to adopt all of EA Technologies recommendations. However, these recommendations could take up to five years to fully implement.

Mr. Madeiros said testing and looking at equipment had already started. When the temporary switch room is up in November, more recommendations will be added gradually, he said. The fire totally destroyed one power switching facility and rendered a second facility useless resulting in a loss of 40 percent of switchboards associated with the Belco generating plant, chairman Collier said.

The switch gear room that exploded was large ? 93 foot long, 21 feet wide and was carrying 22,000 volts of current, he said.

?This investigation has found that a fault occurred in a compound filled busbar chamber which is a sealed non-maintainable item in the switchgear equipment, resulted from insulation breakdown, possibly emanating from the time the original installation,? Mr. Collier said. ?We have endeavoured to question every aspect of this event to understand the causes, determine the reasons for them and ensure we learn from this catastrophic incident.?

The investigators looked at all of Belco?s available information, then forensically examined the switch room, which was damaged by fire and electrical damage.