The measure (House Bill 1091) requires all homes and apartment buildings offered for sale after July 1 to have carbon monoxide detectors near bedrooms.
Homeowners and apartment owners also will have to install detectors if they complete any major renovations or additions.
The bill is named for Lauren Johnson of Denver and the Lofgren family of Denver.
Johnson, a University of Denver graduate student, died of carbon monoxide poisoning in her apartment Jan. 5.
Her mother, Barbara Moilien, said it's a warning to other parents.
"If you are sending your child off to college, make a carbon monoxide alarm the first item on your list that includes a set of sheets, MP3 player or new computer. It will be your least expensive purchase, and in doing so, you may be saving the life of your son, daughter or grandchild," she said, surrounded by friends and family at a Denver firehouse filled with tables of donated carbon monoxide alarms.
Parker Lofgren, 39, a founding partner of investment bank St. Charles Capital, his wife Caroline, 42, and their two children, Owen, 10, and Sophie, 8, were found dead at a home outside Aspen over the Thanksgiving weekend. Friends meeting the family found them.
Caroline Lofgren's brother, Fred Feuerbach, said his family's life-changing tragedy may help others avoid similar grief.
The Centers for Disease Control and Prevention estimate that about 500 people die each year in the United States from carbon monoxide poisoning. It can be caused by a malfunctioning furnace, water heater or stove, or by objects blocking a flue.
Last year, the Colorado Senate rejected a similar measure partly because some members thought it was largely being pushed by manufacturers. Others dismissed it as a "nanny state" bill.
There also were concerns that homebuilders and apartment owners could be held responsible if the equipment failed. This year's bill would not hold them liable.
(Copyright Associated Press, All Rights Reserved)