||Much recent work has been done measuring elevated flare performance with Passive FTIR (PFTIR). This research has validated the use of the PFTIR as a reliable alternative to extractive sampling and provided more detailed insight into flare performance over a variety of flare tip designs, gas compositions, inert concentrations, and assist rates. This study presents the first data collected with PFTIR on the performance characteristics of a ground flare burner array. Testing was conducted on two burner types: pressure-‐assist and steam-‐assist. The effects of exit velocity and assist rates on burner combustion efficiency are explored. Additional testing on the comparative effects of steam dilution vs nitrogen dilution on flare efficiency was also conducted and is discussed in this report.