I was talking to a Caltrans signal tech last week. He was telling about some natural gas traffic signals that the city of Los Angeles, Ca. used way back when. He said that the city of L.A. tested many types of signals in the old days, but the gas powered one was not one of their better ideas. He said that one of the protos caught fire, and exploded.
I had never heard of a gas powered signals before. I don't think that he was pulling my leg, but you never know! Has anyone else heard of a gas powered signal?
Easy