Yesterday in San Francisco's Mission District, firefighters rushed to 3934 Mission Street after reports that a person had been found unconscious following suspected carbon monoxide exposure, according to an alert circulating on a neighborhood safety app that sparked the emergency response.
As detailed by the San Francisco Fire Department Media account on X, the incident was reported through the Citizen safety app and listed at 3934 Mission St. The department shared only a brief update and did not provide any further information about the individual's condition.
(3934 Mission St) Report of Person Unconscious After Carbon Monoxide Poisoning - reported on @CitizenAppSFO https://t.co/ZO395AjwBi
— SAN FRANCISCO FIRE DEPARTMENT MEDIA (@SFFDPIO) March 22, 2026
How Carbon Monoxide Puts People At Risk
Carbon monoxide is a colorless, odorless gas that can quickly build up indoors and cause sudden illness or death. According to the Centers for Disease Control and Prevention, symptoms of exposure can include headache, dizziness, nausea, confusion and loss of consciousness.
What To Do If An Alarm Sounds
Guidance from the San Francisco Fire Department advises residents to evacuate the building immediately, call 911 and move anyone who appears sick into fresh air as quickly as possible. The department also recommends installing carbon monoxide detectors outside sleeping areas and on every level of a home, and warns residents not to go back inside until firefighters or other responders say it is safe.
Local Rules And Prevention
California law requires many homes and rental properties to be equipped with carbon monoxide alarms that meet state standards. The Carbon Monoxide Poisoning Prevention Act (SB 183), along with State Fire Marshal regulations, spells out where alarms must be placed and which devices are approved. The legislative text is available in SB 183.
Anyone near Mission Street who feels unwell or hears a carbon monoxide detector go off is advised to get everyone into fresh air and call 911 right away. While waiting for responders, you can also reach the national Poison Control Center at 1-800-222-1222 for medical guidance.
