Carbon monoxide gets less attention in South Florida than in colder states, because few Miami homes have a furnace. That is a mistake. Gas water heaters, gas ranges, fireplaces, cars in attached garages and, above all, portable generators run during hurricane outages all produce carbon monoxide. CO has no color and no smell, and an alarm is the only way most people will know it is there. This guide covers what Florida law requires, where alarms belong, and the risk that matters most after a storm.
What Florida law requires
Florida's carbon monoxide alarm requirement is in section 553.885 of the Florida Statutes. In short, every separate building or addition to an existing building, other than certain health care facilities, for which a building permit for new construction is issued on or after July 1, 2008, and which has a fossil-fuel-burning heater or appliance, a fireplace, an attached garage, or another feature that can emit carbon monoxide, must have an approved, operational carbon monoxide alarm installed within 10 feet of each room used for sleeping, or at a location the Florida Building Code specifies.
A few things follow from that text:
- It applies to new construction and additions permitted on or after July 1, 2008. It does not, by itself, require alarms in a house built before then that has not had a qualifying addition.
- It is triggered by a source of carbon monoxide: gas or oil appliances, a fireplace, or an attached garage. An all-electric home with no attached garage may not be covered.
- The alarm has to be within 10 feet of each sleeping room, which in most houses means in the hallway outside the bedrooms.
- The statute defines a carbon monoxide alarm as a device that produces a distinct audible alarm and meets the Florida Building Commission's requirements. The details are in the statute itself and the building code it points to.
Whether a specific project needs CO alarms is decided by the building department reviewing its permit. Our guide to Miami-Dade electrical permits explains that process.
Where CO alarms belong, by safety guidance
The law sets a minimum for newer homes. Safety guidance applies to every home with a CO source. The U.S. Consumer Product Safety Commission recommends CO alarms on every level of the home and outside sleeping areas. Its carbon monoxide fact sheet recommends battery-operated alarms or alarms with battery backup, prefers interconnected alarms, and says to keep them away from heating vents and places furniture or drapes could block them. CPSC does not recommend putting them in kitchens or directly above fuel-burning appliances.
The real Miami risk: generators after a storm
After a hurricane, many homes run portable generators for days. The CPSC's May 2026 hurricane season warning calls generators one of the leading causes of post-storm carbon monoxide deaths. Its advice:
- Run a portable generator outdoors only, at least 20 feet from the house, with the exhaust pointed away from doors, windows and vents. The CDC gives the same 20-foot distance.
- Never run one in a garage, even with the garage door open. Open doors and windows do not clear the exhaust fast enough. Do not cook on a charcoal grill in a garage either.
- Install working CO alarms on every level and outside sleeping areas, and test them before storm season.
- If a CO alarm sounds, get outside immediately and call 911.
This matters even in a house that the statute does not cover. A house with no gas appliances and no attached garage still has a CO source the moment a generator is running near it. And because hardwired alarms rely on their backup batteries during an outage, check those batteries before the season starts. Our storm readiness page and post-storm electrical safety guide cover the rest of storm prep. A permanently installed standby generator is installed with its own clearances and permit; see generator permits in South Florida.
Combination smoke and CO alarms
Combination alarms detect both smoke and carbon monoxide in one unit, and they come in battery and hardwired versions. They are a practical way to add CO protection in a hallway outside bedrooms where a hardwired smoke alarm already is, provided the new unit is compatible with the other alarms on the interconnect. They usually announce which hazard they detected, with a different sound pattern or a voice message, which matters because the response is different: for CO, you do not look for the source, you leave.
CO sensors wear out sooner than smoke sensors in many models. Kidde, for example, lists 7 years for its CO and combination alarms, while some newer models are rated for 10. The replace-by date is on the label. Our guide to replacing hardwired smoke detectors explains how to read it.
Symptoms to know
The CPSC describes early CO poisoning as flu-like but without a fever: headache, fatigue, shortness of breath, nausea and dizziness. Higher levels cause confusion, vomiting, loss of coordination, unconsciousness and death. If several people in the house feel sick at once, especially while a generator or gas appliance is running, get everyone outside and call 911, whether or not an alarm has sounded.
Questions people ask
My house was built before 2008. Am I required to have CO alarms?
Section 553.885 applies to new construction and additions permitted on or after July 1, 2008 (statute text). An older home may not be required to have them unless work on it triggers the requirement, but if it has any CO source, safety guidance says to install them anyway.
Can a smoke alarm detect carbon monoxide?
Not unless it is a combination unit. A standard smoke alarm does not sense CO. Check the label: a combination alarm says smoke and carbon monoxide on it.
My home is all-electric. Do I need a CO alarm?
If you have an attached garage or ever run a generator, yes, by safety guidance. Cars and generators are among the most common sources.
Need it looked at?
KRW Electric (EC13012832) troubleshoots and repairs hardwired smoke and CO alarms in Pinecrest, Coconut Grove, South Miami and Miami Beach, with same-day service when scheduling permits. Call (305) 359-7312 and tell us what you are seeing. We will ask a few questions, tell you whether it sounds urgent, and give you the earliest time we have. Our before you call checklist covers what to have ready, and what happens on a repair visit explains the rest.
Reviewed by Kyle White, KRW Electric Company LLC — licensed electrical contractor EC13012832.
