Carbon Monoxide Detector Laws by State

"Do I legally need a carbon monoxide detector?" is a common question — and the honest answer is: it depends on where you live and what type of property it is. In the U.S., CO alarm requirements are typically set by state law and building/fire codes, and they can be tightened further by cities, counties, or local fire authorities.

This page gives a safety-first overview of how carbon monoxide detector laws usually work, what situations most commonly trigger a requirement (rentals, home sales, new construction), and how to quickly verify the current rule for your specific address. It is not legal advice — always confirm with official sources and local authorities.

In 60 Seconds: What Most CO Alarm Laws Have in Common

Most U.S. carbon monoxide alarm requirements follow a similar pattern:

They focus on buildings where people sleep (single-family homes, apartments, hotels, and many short-term rentals).
They often apply when there is an attached garage or fuel-burning equipment (gas/oil/wood appliances), but some states require alarms more broadly.
They specify "approved/listed" alarms and sometimes require hardwired + battery backup in new construction.
They set responsibility rules for owners/landlords vs tenants (installation, testing, replacement).
Local rules can add stricter placement details than the state minimum.

Why CO Detector Laws Exist

Carbon monoxide (CO) is an odorless, colorless gas produced by incomplete combustion. Because you cannot reliably detect CO by smell or sight, alarms are a primary layer of protection. Many jurisdictions adopted CO alarm laws after preventable deaths in homes, apartments, and hotels.

When CO Alarms Are Commonly Required

Even if your state differs in the details, these triggers are common:

New construction and major remodels (especially where permits are pulled).
Sale or transfer of a property (often tied to inspection or certificate requirements).
Rental properties (landlord obligations before move-in and sometimes ongoing).
Hotels, dorms, and short-term rentals (sometimes statewide, sometimes local).
Homes with fuel-burning appliances or attached garages (a frequent scope definition).

CO Alarm Requirements: Top 10 States Comparison

CO alarm requirements comparison for 10 most-searched states
State	Homes	Rentals	Hotels / STR	Penalties
California	Yes	Yes	Yes	Yes
Texas	No	No	No	Yes
New York	Yes	Yes	Yes	Yes
Florida	Yes	Yes	Yes	No
Illinois	Yes	Yes	Varies	Yes
Pennsylvania	No	Yes	No	Yes
Ohio	Yes	Yes	Yes	Yes
Georgia	Yes	Yes	No	Yes
North Carolina	Yes	Yes	Varies	Yes
Michigan	Yes	Yes	Varies	Yes

Table shows 10 most-searched states. See each state page for detailed requirements, citations, and local exceptions.

Who Is Responsible in Rentals: Landlord vs Tenant

Many searches (for example, "landlord carbon monoxide detector requirements") come down to responsibility. In many states, landlords must install compliant alarms before occupancy and maintain them to a specified standard. Tenants are often expected to test alarms and report issues, but replacement responsibility varies.

A practical approach that reduces risk in almost any state:

Landlord/owner: install listed CO alarms in required locations, document installation date/model, and replace at end-of-life.
Tenant/occupant: test monthly (or per manufacturer guidance), keep vents clear, and report chirps/faults immediately.
Everyone: if an alarm sounds or people have symptoms, evacuate first — troubleshooting comes after safety.

Placement Rules: What "The Law" Says vs Manufacturer Instructions

Some laws specify general placement (for example, outside sleeping areas), while others reference code standards. Regardless, the safest baseline is to follow the alarm manufacturer's instructions and any local code requirements. If guidance conflicts, prioritize the stricter requirement and consult your local authority or a licensed installer.

Related guidance pages on this site:

Where to place a CO detector (best locations in homes and apartments).
CO detector placement height (does CO rise or fall?).
How many CO detectors you need (a practical room-by-room checklist).

Hotels and Short-Term Rentals (Airbnb, Vrbo, etc.)

Short-term rental rules can be confusing because you may have three layers: state law, city/county ordinances, and platform policies. A platform may require hosts to disclose whether smoke/CO alarms are present, but local law may set the actual minimum installation standard.

If you host or manage a short-term rental, reduce risk by:

Checking your state and local requirements for rentals/STRs (not just the platform checklist).
Using listed combination alarms only if they meet requirements for both hazards (smoke + CO) where installed.
Documenting tests, battery changes, and end-of-life replacement dates.

How to Check CO Alarm Requirements for Your State and City

Use this verification order (fastest to most authoritative):

Your local fire department / building department (they often summarize what's enforced locally).
State fire marshal / state building code resources (official interpretations and bulletins).
State legislature / official code website (the underlying statute text).
Property management / landlord-tenant guidance for your state (useful, but verify against official sources).

Authoritative national resources:

NFPA — Carbon Monoxide Safety (fire protection standards and CO alarm guidance).
CPSC — CO Information Center (federal consumer safety data and recalls).
NCSL — CO Detector State Statutes (cross-state legislative index).
ICC — International Code Council (model building and residential codes adopted by most states).

Tip: laws can differ for single-family homes, multifamily buildings, rentals, and hotels — so search using the property type (for example, "rental property carbon monoxide detector requirements {state}").

Carbon Monoxide Detector Laws by State (A–Z)

Browse state summaries here (overview + rental/landlord notes where available):

A

C

D

I

K

L

Louisiana CO detector laws

M

N

O

P

Pennsylvania CO detector laws

R

Rhode Island CO detector laws

S

T

U

Utah CO detector laws

V

W

If a CO Alarm Sounds, Safety Beats Compliance

Legal requirements help prevent tragedy, but they don't replace immediate safety action. If an alarm sounds or anyone has symptoms, leave the building and seek help. Do not ignore an alarm just because you're "not sure the law applies."

Related emergency guides:

What to do if a carbon monoxide detector goes off (step-by-step).
CO detector beeping (chirps vs alarm patterns and what they mean).

Frequently Asked Questions

Do you need a carbon monoxide detector if you have all-electric appliances?

It depends. Some states require CO alarms based on attached garages or other risk factors, not just fuel-burning appliances. Even in all-electric homes, a nearby attached garage or shared walls in multifamily buildings can introduce risk. Check local requirements and consider an alarm as a low-cost safety layer.

Are CO detectors required in apartments and condos?

Many jurisdictions include multifamily buildings, especially near sleeping areas. Responsibility can vary by ownership model (building/HOA vs unit owner vs landlord). Always verify the rule for your building type and who maintains alarms.

Are CO alarms required in hotels?

Some states mandate CO alarms in hotels or lodging under specific conditions; others rely on local codes. Hotels may also adopt CO alarms as a risk-management standard even where not strictly required.

What happens if you don't have a required CO detector?

Consequences vary: it may affect inspections, certificates, rental compliance, or liability after an incident. Because outcomes differ widely, treat compliance as a baseline safety practice and confirm details with local authorities.

Is a plug-in CO detector legal?

Some jurisdictions allow plug-in alarms, while others require hardwired units (especially in new construction). The key is that the device must be listed/approved as required and installed in the required locations.

Sources & Verification

For legal accuracy, always verify with official sources for your jurisdiction. Helpful starting points often include state legislative code sites, state fire marshal pages, local building departments, and reputable safety agencies. If you maintain a dataset of state rules, include direct links to official citations for each state and note the update date.

Page last updated: February 18, 2026