Based on the context and the answer, generate a question. 

Context: Especially the first part of the first episode they showed ( two half hour episodes ) . Acetylene torpedoes ! Something went wrong at an acetylene place , and sparked a fire , and all those tanks took off like missiles ! I do n't know why they did n't shut down traffic both ways instead of just one .

Answer:

It is unsafe for people to be so close to the flames and unpredictable tanks .



What would be the reason that shutting down the traffic in both ways would be preferrable ?