The purpose of this research project is to provide a simple yet accurate procedure for calculating the minimum distance required between the outlet of an exhaust system and the outdoor air intake to a ventilation system to avoid reentrainment of exhaust gases. The new procedure addresses the technical deficiencies in the simplified equations and tables that are currently in ANSI/ASHRAE Standard 62.1-2016@ Ventilation for Acceptable Indoor Air Quality (ASHRAE 2016a)@ and model building codes. This new procedure makes use of the knowledge provided in Chapter45of the2015ASHRAEHandbook??HVACApplications (ASHRAE 2015)@ and was tested against various physical modeling and full-scale studies The study demonstrated that thenewmethod is more accurate than the existing Standard 62.1 equation@ which underpredicts and overpredicts observed dilution more frequently than the new method. In addition@ the new method accounts for the following additional important variables: stack height@ wind speed@ and ??hidden?? intake. The new method also has theoretically justified procedures for addressing heated exhaust@ louvered exhaust@ capped heated exhaust@ and horizontal exhaust that is pointed away from the intake