I have a 1 1/2" gas line to re route. It is above a dropped ceiling about 4 ft. and drops down beside block a wall. There is not enough clearance to go a full revolution with my Ridgid iron pipe cutter. What are the chances of causing an explotion if I cut into it with my sawzall? I don't own a ban saw. I have done this on smaller lines that run shorter distances, but this gas line is quite long. This in a school building, I want to be safe as possble. There will kids present at time of work being done.