Carbon monoxide: an alarm on every level, and a check before you seal

No Arizona statute appears in NCSL's compilation (updated Sep 29, 2025), and none was found elsewhere. Local codes may require CO alarms in new construction. Absence not independently confirmed.

Health & Safety Code 17926: owners must install a State Fire Marshal-listed CO device in each existing dwelling unit with a fossil-fuel heater or appliance, fireplace or attached garage, by July 1, 2011 for single-family homes, Jan 1, 2013 for other dwellings and Jan 1, 2017 for hotels and motels. Sellers disclose CO devices on the transfer disclosure form (Civ. Code 1102, per ELI).

C.R.S. 38-45-101 to -106 (per NCSL): existing single-family homes and multifamily units offered for sale or transfer (on or after a specified date) that have a fuel-burning heater or appliance, fireplace or attached garage must have an operational CO alarm within a specified distance of each sleeping room; a similar rule applies to new residential construction. The statute text was not opened; leg.colorado.gov blocked automated access.

D.C. Code 6-751.02: the owner of every new and existing occupied dwelling unit must install smoke detectors and carbon monoxide detectors in accordance with the DC Construction Codes.

F.S. 553.885: every building or addition built on or after July 1, 2008 with a fossil-fuel heater or appliance, fireplace, attached garage or other CO source needs an approved CO alarm within 10 feet of each room used for sleeping (hard-wired or battery, or combination smoke/CO). Does not apply to existing homes unless an addition is built.

Georgia State Minimum Standard One and Two Family Dwelling Code (R313.4.1, R315.2.1, adopted under O.C.G.A. 8-2-20): CO detectors in general sleeping areas of all new one- and two-family homes and townhomes of three stories or less. New construction only.

Carbon Monoxide Alarm Detector Act (430 ILCS 135/10): every dwelling unit must have at least one approved, operating CO alarm within 15 feet of every room used for sleeping; multi-unit structures also need at least one.

Public Safety 12-1101 to -1106: applies to new dwellings using fossil fuel with building permits issued on or after Jan 1, 2008, and to hotels, rooming houses and rental dwelling units. A CO alarm goes in a central location outside each sleeping area; rental units since April 1, 2018 need alarms outside each sleeping area and on each level including the basement; hotels since April 1, 2017. Per NCSL, sellers of single-family homes must disclose fossil-fuel heating and alarm installation.

M.G.L. c.148 s.26F1/2: every residential building with fossil-fuel equipment (furnace, boiler, water heater, fireplace) or enclosed parking must have working, approved CO alarms. Landlords install them and must have them working at the start of each rental. The fire department inspects for compliance on sale or transfer.

MCL 125.1504f (effective Mar 23, 2009): the state construction code may require at least one CO device in new single- and multifamily dwellings, renovations needing a permit, and bedroom additions. Devices go near bedrooms, next to an attached garage and next to fuel-burning appliances, and must be listed to ANSI/UL 2034 or UL 2075. The requirement applies through the adopted residential code; it is not a retrofit mandate for existing homes.

Minn. Stat. 299F.51: every single-family dwelling and every multifamily dwelling unit must have an approved, working CO alarm within 10 feet of each room lawfully used for sleeping. Multifamily owners install and replace alarms between tenancies; occupants maintain them; disabling an alarm is prohibited.

No Missouri statute appears in NCSL's compilation (updated Sep 29, 2025), and none was found elsewhere. Local ordinances or adopted building codes may apply. Absence not independently confirmed.

N.J.S.A. 52:27D-133.3 to -133.5: CO detectors in one- and two-family homes at initial occupancy or change of occupancy (sale or new tenancy); separate statutes cover hotels, multiple dwellings and rooming houses unless no CO hazard exists. Fire Code rules (N.J.A.C. 5:70-4.9(d), 4.19) require CO detection in existing buildings with a fuel-burning appliance or attached garage.

Executive Law 378(5-a): every one- or two-family dwelling, condo or co-op dwelling unit, and multiple dwelling must have an operable CO detector where the unit has CO-emitting appliances, devices or systems, or an attached garage. The statute sets no construction-date cutoff.

G.S. 42-42(a)(7): landlords must provide at least one operable CO alarm per rental unit per level in units with a fossil-fuel heater, appliance or fireplace, or an attached garage. Alarms must be listed to ANSI/UL 2034 or 2075, working at the start of each tenancy, and repaired or replaced within 15 days of written notice. Per NCSL, G.S. 143-138 also authorizes State Building Code rules requiring CO detectors in dwelling units with fossil-fuel sources or attached garages.

ORS 105.836-.842: one- and two-family dwellings and multifamily housing with a CO source (fuel-burning heater, fireplace, appliance or cooking source, or an attached garage) can't be sold or transferred unless working CO alarms cover all sleeping areas; buyers may sue for the greater of actual damages or $250 per unit. ORS 90.317: landlords must provide CO alarms in such units and give written testing instructions; CO alarms are a habitability requirement.

Act 121 of 2013 (Carbon Monoxide Alarm Standards Act, effective Dec 18, 2013): on sale of a residential building the seller must disclose CO detector information on the property disclosure statement. Each apartment in a multifamily dwelling with a fossil-fuel heater or appliance, fireplace or attached garage must have an approved, centrally located CO alarm near the bedrooms (owner installs; tenant maintains). Municipalities may adopt stricter rules.

No statewide residential CO-alarm statute found. NCSL lists only Hum. Res. Code 42.060, which requires CO detectors in qualifying day-care centers, group day-care homes and family homes. Municipalities apply the IRC as it existed May 1, 2012 as their residential code (Loc. Gov't Code 214.212); its CO-alarm section was not verified here.

Per NCSL: Va. Code 27-94 et seq. and 36-97 et seq. set a statewide standard for installing and maintaining smoke and CO alarms in rental properties under the Statewide Fire Prevention Code. The landlord's annual certification (Va. Code 55.1-1220) covers smoke alarms. The fire-code CO provisions were not opened.

RCW 19.27.530: CO alarms required in newly built residential occupancies (code by Jan 1, 2011) and all other residential buildings by Jan 1, 2013. Owner-occupied single-family homes legally occupied before July 26, 2009 are exempt, but when one is sold the seller must install CO alarms before the buyer occupies it.