Energy conservation strategies often distract attention fromother core design objectives, including occupant health, productivityand avoiding threats to the building structure’s long-termintegrity. CO2-based demand control ventilation (DCV) is an energy-conserving strategy that, in some cases, has sacrificed severalof these fundamental design objectives. Instead we have embracedshort-term energy cost savings and accepted greater risks to occupanthealth, diminished worker productivity, increased maintenancecosts, and life-cycle cost for the structure.