CO Detector Rules in Hawaii: Honolulu and Local Code Requirements

Last verified: February 16, 2026

Hawaii carbon monoxide detector laws are primarily enforced through county and city code adoption rather than one blanket statewide residential mandate. Hawaii's state residential code adopts IRC language by reference, but day-to-day obligations for permits, inspections, and operating properties are implemented locally.

Honolulu provides explicit detector requirements for transient vacation units and bed-and-breakfast homes when listed fuel-powered conditions exist, including placement near sleeping areas. Because enforcement can differ by island and municipality, owners should verify local amendments before construction, turnover, or licensing activity.

The strongest compliance approach is to keep local code-edition records, trigger-condition notes, installation documentation, and test logs in each property file. This local-first structure means multi-island operators cannot rely on one statewide checklist for every occupancy.

Quick Safety Summary

CO detector requirements for Hawaii
Applies to homes?	No
Applies to rentals?	Not confirmed — check local codes
Applies to hotels/STRs?	Not confirmed — check local codes

How to verify: Hawaii 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?

Where to Install CO Alarms

Honolulu transient-vacation and bed-and-breakfast context requires CO detectors in each transient occupant bedroom and each hallway connected to a transient occupant bedroom when covered fuel-powered conditions are present.

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

Device Requirements

Honolulu building code amendment language references IBC 2018 Sections 915.4 and 915.5 and includes specific exceptions in local text.

Enforcement

Enforced by: Honolulu Department of Planning and Permitting for local registration and ordinance enforcement, with local code officials handling inspection workflow.

Enforcement typically occurs:

During local registration and renewal review for covered transient-vacation and bed-and-breakfast use.
During complaint-based or code-compliance enforcement by local authorities.

Additional Notes

No standalone statewide CO alarm statute identified as of 2026. Requirements derive from IRC adoption under HRS 107-25 and local enforcement.
Hawaii implementation is primarily local for practical compliance purposes, so obligations can differ across counties.
The cited Hawaii sources do not establish one universal statewide mandate covering all private homes and rentals.

Official Sources & References

Hawaii Revised Statutes Section 107-25 (State Building Codes; Requirements) — HRS 107-25 listing adopted model codes including the IRC (state code, accessed 2026-02-18)
No standalone statewide CO alarm statute identified as of 2026. HRS 107-25 is the enabling statute that adopts the IRC (which contains Section R315 CO alarm provisions) as part of the Hawaii state building codes. CO requirements enter Hawaii law through this adoption chain.
Hawaii State Residential Code (2018 IRC adoption by reference) — Adoption language for 2018 IRC by reference (building code, accessed 2026-02-16)
Official statewide residential code adoption framework; local jurisdictions implement and enforce code pathways.
City and County of Honolulu Ordinance 24-14 (Bill 53 CD2) — Restrictions and standards for transient units and related detector requirements (local ordinance, accessed 2026-02-16)
Provides explicit smoke and carbon monoxide detector rules in covered transient lodging contexts.
City and County of Honolulu Building Code Amendment (Bill 58 CD1) — Local CO alarm language referencing IBC 2018 Sections 915.4 and 915.5 (local ordinance, accessed 2026-02-16)
Details local detector framework, exceptions, and system alternatives for covered conditions.

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

Is there a single statewide Hawaii law requiring CO detectors in every home?

Hawaii does not currently operate with one blanket statewide CO detector statute that applies to every private home in the same way across all islands. Requirements are generally implemented through adopted code frameworks and county-level enforcement. The Hawaii State Residential Code adoption documents still matter, but owners should confirm local amendments and inspection expectations before relying on a statewide assumption. This is especially important for permit-based work and occupancy transitions.

Which Hawaii occupancies have clearly published CO detector rules today?

Honolulu has explicit detector language for certain transient vacation units and bed-and-breakfast contexts, including bedroom and hallway placement when qualifying fuel-powered conditions exist. Those local rules provide the clearest published operational baseline in the currently cited materials. For properties outside those occupancy categories, the answer depends on local adoption and enforcement practice. Owners should map property type, fuel source conditions, and jurisdiction before finalizing compliance decisions. In Hawaii, verify Honolulu DPP and county code references before final permit sign-off.

How should owners handle county-by-county differences in Hawaii?

The safest workflow is a jurisdiction-specific checklist for each island or municipality, not a single statewide template. Start by confirming the adopted code edition, then record which trigger conditions apply to each property and what local inspectors expect for documentation. This helps avoid failed inspections or licensing delays caused by assumptions taken from another county. In Hawaii, compliance quality is usually determined by local implementation details rather than broad statewide wording.

For Hawaii all-electric dwellings, which risk conditions can still require alarms?

Not always. Even when a unit appears all-electric, local code interpretation may still require alarms based on attached structures, nearby combustion sources, or occupancy configuration. Owners should verify the real building risk profile and local enforcement position before treating any unit as exempt. Installing alarms in borderline scenarios is a common risk-control choice, especially for multifamily or hospitality settings where adjacent spaces can create carbon monoxide exposure pathways. Hawaii code officials and Honolulu DPP guidance should be cited in exemption files.

What placement guidance is clear in Honolulu published detector rules?

The cited Honolulu ordinance language requires carbon monoxide detectors in each transient occupant bedroom and in each hallway connected to a transient occupant bedroom when covered fuel-powered conditions are present. That gives operators a concrete baseline for these lodging categories. Device selection, installation method, and test intervals should also be aligned with associated building-code references and local enforcement expectations. Keeping inspection records and test logs is essential for renewal and complaint response. Honolulu Ordinance 24-14 and Bill 58 references should appear in internal compliance checklists.

How do Hawaii local-rule workflows compare with California statewide practice?

Hawaii compliance often depends on municipality-level code pathways, while California relies more heavily on broad statewide statutory language with local enforcement layered on top. Multi-state operators should maintain separate playbooks and avoid copying one checklist between these states. Before aligning procedures for Pacific-region properties, review California CO detector laws and map differences in triggers, scope, and inspection workflow. Hawaii operators should map Honolulu Ordinance 24-14 against California statewide triggers before using one vendor scope.

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