Conn. Gen. Stat. § 29-315b: Temporary installation of smoke and carbon monoxide detectors and warning equipment in one and two-family residential buildings during interior alterations or addition.

Whenever any private residential dwelling designed to be occupied by one or two families is occupied during interior alterations or additions requiring a building permit, the temporary installation of battery-operated smoke detection and warning equipment and, if there is a fuel-burning appliance, fireplace or attached garage present, battery-operated carbon monoxide detection and warning equipment shall be required in the vicinity of, and during the performance of, such alterations or additions. Such equipment shall be of a type or technology that is tested and certified pursuant to standards issued by the American National Standards Institute or Underwriters Laboratories. Such equipment may combine smoke and carbon monoxide detection technology into a single device.