Someone recently reported not being able to find Broan fan curves that I referenced in a message. The link below documents the curves for several kitchen ventilation fans.

http://www.broan.com/common/productDigitalAssethandler.ashx?id=8659c5bb-9d4a-4e5a-85fa-e888a811741b

The next link, while for a bathroom fan, shows how pressure losses with flow are plotted to find the actual flow at the point of intersection.

http://www.manualslib.com/manual/218734/Broan-Nutone-671r.html?page=2

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