hi guys.. is it true that hood's ventilation cannot be more than 10ft?

i see.. do you know roughly how much the suction power is needed for the length lesser than 15ft ? for those below 10ft, i guess would be at 1000AF right ?

another question, will there be any oil clog in between the hose if it is too long? any other issue would encounter if using it in long run?

thanks for the info =)