I have no idea how often they do this. The few times that I’ve had to use a port-a-john in this park (during the winter months the park locks and shuts down the permanent bathrooms, my guess because then they can shut off the water so the pipes won’t freeze) I’ve seen an inspection list glued on the inside wall. By the dates that are written they get checked out once a week. Perhaps when the list is filled, that means that particular port-a-john needs to be switched out.

This is probably more port-a-john talk and information that you’ve ever wanted to read.