Carbon Monoxide Notice Rules for NYC Landlords
Carbon monoxide has no smell and no color, which is exactly why NYC takes CO alarms seriously. For landlords, the rules cover who installs the alarm, where it goes, who maintains it and what notice goes in the lobby.
The quick answer
In short: Owners must install an approved CO alarm in each apartment of a building with a fuel burning device or enclosed garage, within 15 feet of the main entrance to each sleeping room, and post a CO notice in a common area. Tenants keep the alarms working. The rules come from HMC Section 27-2045 and 28 RCNY Chapter 12.
Owner duties
- 1InstallAn approved CO alarm in each apartment, placed within 15 feet of the main entrance to each sleeping room.
- 2ReplaceWhen the alarm reaches the end of its useful life, and between tenants if it's missing or not working.
- 3Post the noticeIn a readily visible common area, explaining owner and tenant duties.
- 4Keep recordsOf installation, and of any tenant reports about alarms.
Tenant duties
Tenants keep the alarm in working order, replace batteries as needed and tell the owner if an alarm is missing, stolen or not working. The notice in the lobby is how tenants learn this, which is why HPD requires it.
Our smoke and CO notice covers owner and tenant duties in clear, bold type. Order the smoke and CO notice, $45
What owners may charge
HPD's sample CO notice lets owners charge tenants for the alarm: $25 for a CO alarm, $50 for a combined smoke and CO unit, payable within one year of installation. Many owners skip the charge, but if you bill, follow the rule and keep records.
Which buildings need CO alarms?
Any building with a fossil fuel burning device, like a gas stove, boiler or water heater.
Buildings with an enclosed parking garage need alarms on the garage floor and floors directly above and below.
No fuel burning device and no garage usually means no CO alarm requirement. See Gas vs All Electric.
Save space with a combined notice
Most owners post the CO notice together with the smoke detector notice. You can also fold in the natural gas detector and gas leak notices with one combined notice. With the natural gas detector deadline coming, combo alarms that detect both CO and natural gas are worth a look.
What this looks like in practice
Say a tenant moves out of a 2 bedroom in a Queens building and the CO alarm is gone. Before the new tenant moves in, the owner installs a new alarm within 15 feet of each bedroom door, notes the date and model in the building's records, and checks that the lobby notice is still up. Ten minutes of work, and the apartment is ready.
Tips from our shop
- Test at every turnover.
Press the test button before handing over keys, and check the door fire safety notice at the same time.
- Write down the install date.
Alarms expire. A simple log tells you when to replace them.
- Keep the notice current.
Rules have been updated over the years. Make sure your sign uses current wording, and see the checklist for the rest.
Official sources: HPD CO posting notice, 28 RCNY Chapter 12, HPD Required Signage.
Quick answers
Where do CO alarms go in a NYC apartment?
Within 15 feet of the main entrance to each sleeping room, following the manufacturer's instructions.
Can I charge tenants for the CO alarm?
HPD's sample notice allows $25 per CO alarm or $50 for a combined smoke and CO unit, payable within one year.
Do rented 1 and 2 family homes need CO alarms?
Yes, alarms are still required in homes with fuel burning devices. See our 1 and 2 family guide.
Not sure what your building needs?
Send us your address and number of apartments. We will tell you exactly which signs to order.
General information based on the NYC HPD Required Signage page as of November 2026. Not legal advice. HPD Signs NYC is not affiliated with the City of New York or HPD. Prices may change. Check nyc.gov/hpd for the latest rules.