Bus fires: fleet will stay in service PREVIOUS FIRE: A bus was destroyed by fire in Munster. PERTH'S gas-fuelled bus fleet will not be taken off the road because it would cripple public transport, despite three of the vehicles catching fire since December last year. The Public Transport Authority is investigating a bus fire at the Welshpool depot last night which destroyed one gas bus and damaged another. Last night's blaze involved the third gas bus to catch fire in recent weeks, with the first in December and the second in February. A bus was destroyed in Munster in a December fire preventing investigators from examining the vehicle. The bus that caught fire in Bentley last month forced 20 passengers to flee the vehicle but was still tact for investigators. Each bus is worth about $500,000 and despite $1.5 million of bus now lost to the fires and Transport Workers Union drivers threatening to walk off the job because of safety fears, the vehicles will not be shut down. "We've got about 1250 buses in the Perth fleet, the gas buses represent about 40 per cent of that," PTA spokesman David Hynes said. We've got about 500 gas buses, to take them off the road would absolutely cripple the bus services. Mr Hynes said it was now a matter of the PTA "managing the fires." "What we've done is, we've installed fire suppression equipment and then after the latest fire in February there was a number of steps put in place," he said. One of those was to substantially upgrade the fire suppression equipment that we have. Each of the gas buses has tubing around the engine bay and when the temperature reaches a certain level, a fire suppression fog is dispersed through seven nozzles into the bay for 45 seconds. After the February fire, the PTA has moved to increase the number of nozzles to 11 and the spray time to 90 seconds. "That upgrade, and it's a fairly major upgrade, will take place on every gas bus we have and work on that actually starts this week," Mr Hynes said. Mr Hynes said the works were originally planned to finish by June 30 but those works will now be sped up. He also said the PTA was working closely with the drivers, contractors and union in fixing the problem. "I can understand the drivers would be concerned, we're doing everything we can," he said. Mercedes and the investigators are working with the PTA to find a solution, with all the planned upgrades expected to cost $1.5 million. "We're working to stop the fires completely, but if we can't stop the fires the next best thing is to put it out immediately," Mr Hynes said.