Free Illinois Carbon Monoxide Detector Disclosure

Start with the duty, then read the exemption, because they live in different sections. 430 ILCS 135/10(a) requires every dwelling unit to be equipped with at least one approved carbon monoxide alarm in an operating condition within 15 feet of every room used for sleeping purposes, and 430 ILCS 135/10(b) applies the same requirement to every structure containing more than one dwelling unit. Section 10 itself attaches no fuel-burning, garage or fireplace condition. The exemptions sit separately at 430 ILCS 135/20 and are narrow, and one prong of the main exemption is decided by your local building commissioner rather than by you.

Two, and both are tightly drawn. The first covers a residential unit in a building that (i) does not rely on combustion of fossil fuel for heat, ventilation, or hot water, (ii) is not connected in any way to a garage, and (iii) is not sufficiently close to any ventilated source of carbon monoxide, as determined by the local building commissioner, to receive carbon monoxide from that source. All three must hold together. The second covers a unit not sufficiently close to any source of carbon monoxide to be at risk, again as determined by the local building commissioner. Because that determination is a local official’s, an all-electric building is not self-exempting.

Within 15 feet of every room used for sleeping purposes, under 430 ILCS 135/10(a). The measurement runs per sleeping room, not per floor and not per unit, so a unit with bedrooms at opposite ends of a long hallway can require more than one alarm to comply. “Dwelling unit” is defined at 430 ILCS 135/5 as a room or suite of rooms used for human habitation, and expressly includes a single family residence as well as each living unit of a multiple family residence and each living unit in a mixed use building. Record the actual locations on the disclosure so the placement is documented at move-in.

430 ILCS 135/10(c) splits the duties precisely. It is the responsibility of the owner of the structure to supply and install all required alarms, and the owner must ensure the batteries are in operating condition at the time the tenant takes possession of the dwelling unit. The tenant tests, provides general maintenance, replaces required batteries thereafter, and must notify the owner or the authorized agent in writing of any deficiencies the tenant cannot correct. The tenant must also give access so those deficiencies can be corrected. Keep the tenant’s written reports; they are the record that fixes when your repair obligation started.

Yes, and it is the duty this disclosure form discharges. The last limb of 430 ILCS 135/10(c) makes the owner responsible for providing one tenant per dwelling unit with written information regarding alarm testing and maintenance. That obligation stands independently of supplying and installing the alarms themselves, which is exactly why it is the one most often missed: nothing physical is absent from the unit when it is skipped. A signed, dated tenant acknowledgment at move-in converts an easily disputed conversation into a record you can produce later.

430 ILCS 135/10(d) permits an alarm that is either battery powered, plug-in with battery back-up, or wired into the structure’s AC power line with secondary battery back-up. Under 430 ILCS 135/10(a) a combined smoke and carbon monoxide unit is acceptable provided the combined unit complies with the administrative code, reference standards and departmental rules for both device types and emits an alarm in a manner that clearly differentiates the hazard. 430 ILCS 135/5 defines an approved alarm as one complying with Illinois State Fire Marshal rules, bearing the label of a nationally recognized testing laboratory, and meeting the most recent Underwriters Laboratories or Canadian Standard Association standards.

They are criminal, not merely civil. 430 ILCS 135/15(a) makes willful failure to install or maintain in operating condition any carbon monoxide alarm required by the Act a Class B misdemeanor. 430 ILCS 135/15(b) makes tampering with, removing, destroying, disconnecting, or removing the batteries from any installed alarm a Class A misdemeanor on a first conviction and a Class 4 felony on a second or subsequent conviction, except in the course of inspection, maintenance or replacement. Those exposures sit on top of any habitability or negligence claim a tenant or an injured occupant might bring separately.

430 ILCS 135 is statewide law and applies inside Chicago as elsewhere. Chicago then layers its own requirements through the municipal building code and the Residential Landlord and Tenant Ordinance, and other Illinois municipalities do the same, which is precisely why 430 ILCS 135/20 hands the “sufficiently close to a source of carbon monoxide” question to the local building commissioner in the first place. Treat the state Act as the floor, then check the local code and any ordinance for that address before deciding an alarm is unnecessary. Never state a Chicago rule as Illinois law, or an Illinois rule as the Chicago answer.