My house has wide plank pine floors. The floor boards vary in width from
around a foot to maybe two feet. Recently I decided to fix up the
bathroom floor. I removed two layers of bad old tile flooring to get
down to the original pine floor in the bathroom. This is a bathroom of
around 10" by 20" (originally not a bathroom since the house was built
in 1820 before homes had bathrooms).

I have sanded the floor down in the room and my plan is to coat it with
polyurethane. This bathroom has a sink, toilet and tub/shower. My
question is, is polyurethane over a pine floor acceptable in a bathroom?
Does anyone out there have a wood floor in a bathroom and does a coating
like this protect it enough from the potential water damage to the floor?