Suitable bathroom door vent?

[Glengyle]

I have fitted a Vent Axia ACM100 fan in the loft to extract from the bathroom (10 cubic metres). I now need to fit a vent in the bathroom door. Will this vent be suitable for the above or is there a minimum requirement for the size of vent?
http://www.screwfix.com/prods/13616/Heating-Cooling/Ducting/Fixed-Louvre-Vent-Grey-9-x-3

 

[holmslaw]

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[Glengyle]

Thanks holmslaw. Just checked and there is about an 5mm gap already.