Can anyone shed any light on this:

I have a float valve in the loft
I want to add a submerged fill so hat it fills quietly
Just adding a section of pipe breaks WRAS rules as ther eis nothing to
prevent bak siphon
Presumably however as long as I have a WRAS approved check valve
upstream of the valve I am ok -any water suked back up the pipe can't
get past the valve. I know this is ok for outside taps, so ought to be
ok here...

Any thoughts?

Cheers,

Ben