Secondly I have a slight concern over the stated max volume of air it can take. It states that the max is 425m3/h, what would be the issues if this was exceeded? My extracter works on 1930m3/h which I appreciate will be significantly reduced as the filters get blocked, but will still be above this max limit? I'm just struggling to see what issue the increased air flow would have as none of the other arms ive seen have a max flow rate.