CO Detectors in Missouri: Lodging Rules and Local Code Variations

Last verified: February 17, 2026

Missouri carbon monoxide detector laws are clearest at the statewide level for lodging establishments under 19 CSR 20-3, especially where fuel-fired equipment, wood-burning fireplaces, or attached parking-garage conditions create risk. That statewide lodging framework includes placement constraints, testing expectations, and hardwired-with-backup power requirements over time.

Outside the lodging context, broad home and rental obligations are less uniform at the state level and often depend on local code adoption by city or county authorities. Missouri operators should separate lodging compliance from residential local-code review instead of assuming one statewide rule applies to every occupancy.

Defensible practice includes written scope analysis, installation records, test logs, and documented communication with the authority having jurisdiction.

Quick Safety Summary

CO detector requirements for Missouri
Applies to homes?	Not confirmed — check local codes
Applies to rentals?	Not confirmed — check local codes
Applies to hotels/STRs?	Yes

How to verify: Missouri does not have a clear statewide mandate for all property types. Contact your local building department or fire marshal to confirm requirements for your specific address and property type.

When Are CO Alarms Required?

Buildings with fuel-burning appliances
Buildings with attached garages
Missouri lodging regulation also references wood-burning fireplace risk in covered establishments.

Where to Install CO Alarms

Install in locations required by 19 CSR 20-3 and manufacturer instructions.
Detectors should not be placed within five feet of gas-fueled appliances or near cooking or bathing areas under the cited lodging rule.
For attached parking garages, detectors are required in rooms adjoining or sharing a common ventilation system with the garage.

For detailed placement guidance beyond legal requirements, see where to place carbon monoxide detectors.

Device Requirements

Primary power from building wiring with battery backup under 19 CSR 20-3 lodging requirements.
Battery-only units are not a long-term substitute where the lodging rule requires hardwired backup pathways.
Ongoing testing and operational condition are required within the lodging inspection framework.

Landlord and Tenant Responsibilities

The cited statewide sources do not establish one complete landlord-tenant duty matrix for all Missouri residential rentals.

Enforcement

Enforced by: Missouri lodging administrative authority and inspection program, with local building or fire authorities where local codes apply.

Enforcement typically occurs:

During lodging inspection and licensing workflow for covered establishments.
During enforcement follow-up when detector deficiencies are documented.

Penalties for Non-Compliance

The cited Missouri lodging detector rule does not provide a stand-alone fine schedule specific to carbon monoxide detector violations.

19 CSR 20-3 establishes requirements and inspection expectations; separate enforcement pathways may apply through licensing actions.

Additional Notes

Missouri statewide certainty is strongest for lodging establishments under 19 CSR 20-3.
Residential compliance for homes and rentals should be verified through local adoption and enforcement channels.

Official Sources & References

Missouri Code of State Regulations 19 CSR 20-3 — Life safety operation and maintenance requirements for lodging establishments (state code, accessed 2026-02-17)
Primary statewide lodging source for detector scope, placement constraints, and testing obligations.
Missouri Revised Statutes section 315.005 — 315.005 (state code, accessed 2026-02-17)
Chapter 315 definitions used in state carbon monoxide alarm context.
Missouri Revised Statutes section 315.012 — 315.012 (state code, accessed 2026-02-17)
Companion statute reference in Chapter 315 for statewide carbon monoxide alarm interpretation.

Disclaimer: This information is provided for general guidance and is not legal advice. Requirements may vary by city, county, and building type. Always verify current rules with local authorities and official sources.

Frequently Asked Questions

Which Missouri source is most explicit about CO detector duties?

Missouri Code of State Regulations 19 CSR 20-3 is the clearest statewide source in this dataset because it sets concrete detector duties for lodging establishments. The rule defines risk-based triggers, placement constraints, operational expectations, and testing workflow for covered properties. Teams should start with occupancy classification to confirm whether a property is regulated as lodging. Missouri operators that skip this first step often apply the wrong checklist and fail inspection. Keep the exact 19 CSR 20-3 section citation in every compliance file.

Where should detectors be placed for covered Missouri lodging spaces?

Under Missouri 19 CSR 20-3, detectors should be installed per rule language and manufacturer instructions, with specific restrictions such as avoiding placement within five feet of gas-fueled appliances and avoiding cooking or bathing zones. The rule also requires detector coverage in rooms adjoining or sharing ventilation with attached parking garages. This makes room adjacency and ventilation mapping a practical compliance step, not just a design detail. Missouri lodging teams should document location rationale and keep that record available for inspection review.

For Missouri noncompliance cases, which enforcement path usually escalates first?

The cited detector language in Missouri 19 CSR 20-3 does not present a separate fine table specific to carbon monoxide detectors. In practice, enforcement risk can still be meaningful because inspection and licensing actions may follow if life-safety violations remain uncorrected. Operators should treat unresolved findings as high-priority corrections and keep dated proof of remediation. Missouri compliance programs work best when deficiency notices, repairs, and retest outcomes are tracked together under the same property record.

Do Missouri rentals follow one statewide landlord CO detector rule?

The statewide Missouri sources cited here are most specific for lodging and do not provide one universal landlord-tenant matrix for every rental property. Many residential obligations can therefore depend on local code adoption and local enforcement practice. Landlords should confirm city or county requirements before move-in and turnover events, then preserve written citations in lease and maintenance files. Missouri rental portfolios should not assume that a lodging rule automatically governs apartments or single-family rentals.

Does Missouri require hardwired CO detectors in all properties?

Not in a single statewide way for every occupancy. Missouri 19 CSR 20-3 describes hardwired with battery-backup expectations in the lodging context and ties device operation to ongoing inspection discipline. Outside that statewide lodging scope, homes and rentals can be governed by local code choices. Owners should avoid blanket assumptions and instead align each property with the applicable rule set. Missouri documentation should identify occupancy type, governing code source, and installed device power method.

How does Missouri compare with Illinois for multi-state policy work?

Missouri in this workflow is anchored by lodging-focused statewide regulation plus local residential variability, while Illinois compliance relies on a different statewide statutory structure for many residential settings. Multi-state operators should keep separate policy tracks instead of using one Midwest template. For cross-state benchmarking before finalizing SOPs, review Illinois CO detector laws and map differences in occupancy scope, enforcement channels, and documentation controls. Missouri teams should keep lodging citations separate from local residential notes.

Practical CO Detector Guides

Beyond legal requirements, these guides help you choose, install, and maintain CO alarms:

Where to place carbon monoxide detectors — room-by-room placement recommendations
CO detector beeping patterns — what different alarms mean
What to do if your detector goes off — emergency response checklist
CO resources and links — official agencies and safety information