For A ___________ Ventilation Operation - The ___________ Should Be Placed _______ Feet Outside The Opening. The Exhaust Should Be Directed ___________ The Opening So The Area Will Fill With Fresh Air. The Influx Of Air Creates A ____________ Interior Pressure. This Pressure Causes The __________ To Seek A Means Of _______. Firefighters Control The ______________ By Providing Openings - ________ - Controlling The Avenues Of Ventilation.