Complex sentence: After attempting to remove his arm from the machine, he fails and this results in him having to be released by the fire department, who discover he is only holding on to the can and that his arms are not trapped.
Split into simpler sentences: After attempting to remove his arm from the machine, he fails and this results in him having to be released by the fire department. The firefighters discover he is holding on to the can and that his arms are not trapped.