411A
Of course, in FAA-land it's done just a tad differently.
No such thing as an approach 'ban', the pilot decides whether to land (or not) depending on what he actually sees, at minima.
There's no explicit approach 'ban' as in Canada or the UK. But I wouldn't want to chance my arm against an FAA enforcement action, by landing with an RVR below minimums, based on what I actually see at minima. You can argue tower viz. v in-flight viz, but there's no arguing with RVR.