Good evening Lylebrown00 / Marinel1,
There is a checklist to ensure all procedures had been followed. Off Course back up blower and generator shall be available. The fuel in the generators and blower rotation direction shall be checked.
I have experience when the roof is raise about 1 foot we lowering down by opening the roof manhole wider. And the roof went down slowly.
But it would be different case if the roof already raised in half way.