This technical bulletin examines nitrogen (N2) consumption across the NU-5800 series CO2 incubators (NU-5831 and NU-5841, 115V and 230V models) equipped with O2 control. Experiments were conducted with CO2 at 5%, RH at 90%, and varying O2 levels (5% and 0.5%) to measure consumption under realistic operating conditions. Results show operational durations ranging from 23 hours to over 3 days with a full N2 tank, influenced by environmental setpoints and door openings. These findings highlight the importance of careful setpoint management and operational strategies to optimize efficiency, reduce resource consumption, and extend tank life. Labs using NU-5800 series incubators can leverage these insights to improve performance and minimize operational costs.