A BUSHfire was sparked in hot conditions near Tarcutta yesterday when a caravan came loose from a car.The car was southbound on the Hume Highway when it lost the caravan, two kilometres south of Tarcutta, shortly before 3pm.But what started as a minor accident had the potential to turn into a major disaster for the Rural Fire Service (RFS).Forty firefighters and 13 tankers were rushed to the site to stop the flames spreading in the 35 degree heat.Two water-bombing aircraft were also dispatched from Forest Hill.Thick smoke and limited visibility caused police to close the southbound lane of the highway for more than an hour.By 4.30pm, RFS spokesman James Smith said firefighters were mopping up."About 100 hectares were lost and there were a number of properties nearby but none were under direct threat," he said. Earlier in the day, a malfunction in a piece of welding equipment is believed to have caused an explosion and fire in a shed at Stockinbingal.The workshop on Temora Road went up in flames about 10am.The explosion that started the fire was so intense, shrapnel was sent shooting about 80 metres from the shed and started several spot fires.No one was injured and firefighters had the main fire and spot fires under control within an hour.