Not sure why a cutting torch would be less
safe than a plasma cutter, you've still got very hot particles flying
around, the fire hazard is going to be about the same.

I think it's more the gas itself that he doesn't want around. If it were
up to me, we would use a gas torch.


I think you'll find that a cutting torch won't work with cast iron anyway.
Maybe you could just heat it as hot as you can and throw some cold water
over it.