Oklahoma Administrative Code 340: 110-3-97(e):
For child day care facilities, one operable CO detector must be installed according to the manufacturer’s instructions when there is a fuel-burning appliance in the facility. (Effective date: May 25, 2000)

Adoption of 2009 IRC
Detached one- and two-family homes and townhouses of not more than three stories containing fuel-burning appliances or attached garages must install CO alarms in the general vicinity of the sleeping area. (Effective date: July 15, 2011)