Carbon monoxide detectors save lives. Why aren't they required everywhere?

Appleton, Wisconsin — After becoming sick with carbon monoxide poisoning in her home, Ashley Wilson started asking questions about CO alarms in her children's schools. 

She's discovered something that experts already know. CO alarms are not required in most buildings, including her son's elementary school. 

"I was surprised," Jack Knaack, the principal of Richmond Elementary School, told consumer correspondent Ash-har Quraishi.