i normaly have decent size bonfires and tip a bit of petrol round and light it no probs .made a big mistake chucked a load round and forgot my blowlamp went and got it . it was a hot evening and never gave it a thought . all the fumes had time to built up and i lit itThe issue with bonfires, a large amount can quickly evaporate into a cloud of explosive mixture. The result can be an explosion rather than a contolled burn, needs a bit of care!