Welding tank explodes during repairs

A Tank Explodes during Welding Repairs after Passing a Flammable Gas Test... 

A tank explodes during welding repairs after passing a flammable gas test... 

The objects worked on and the environment need proper controls as well. A common problem is repair of a container that had a fuel in it. The vapors can ignite and explode and result in severe injury or death. To prevent such events, containers need to be cleaned and flushed out to remove residual fuel. Another method is filling such containers with water or sand during welding. That fills the tank so there are no remaining vapors. 

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