... on a gas tank?
http://www.570news.com/news/topstory/article.jsp?content=20081025_060638_16464

Saturday, October 25, 2008 - 06:06 AM

570 News
The Ministry of Labour continues to investigate an explosion-fire at a Kitchener auto repair shop.
Two men were taken to hospital to be treated for minor burns on Friday night.
Lisbon Automotive Services is located at Stirling Avenue and Mill Street.
Regional Police tell 570 News two men were trying to remove a rusty bolt on a gas tank with a cutting torch when fuel underneath the vehicle ignited. A bucket of fuel nearby was also set on fire.
It took crews 15 minutes to get the blaze under control. One man suffered minor burns while the other has second degree burns to his forehead, cheeks and arms.

never seems like smart idea to me... although no mention of the fuel inside the tank igniting