Brief Description of Incident:
While spreading primary phases, the top four feet of a pole split. The pole split enough to kick the quarter brace lag out of the temporary arm. Two phases to the north were spread to a hot arm. While preparing to move the south phases, the pole top split. The temporary spreader arm flipped with the north side falling down due to the weight until it hit the south phases, which were still clipped in.
We should have inspected the pole better before beginning work and possibly installed a split bolt below temporary arm to prevent the pole from splitting. Our contributing factors include complacency/overconfidence, unexpected equipment conditions