Fire and Intrusion: ICC strengthens CO smoke detector codes

System Sensor’s David George looks at the ICC’s new requirements for carbon monoxide, smoke detectors


The International Code Council (ICC) has published new requirements for carbon monoxide (CO) detection and revised requirements for smoke detectors. These provisions are covered in the ICC’s International Residential Code (IRC) for one- and two-family dwellings and townhouses and occurred when the ICC membership overturned two recommendations of the IRC committee.

The ICC implements the IRC as a model code regulation, which is proposed, debated and created for adoption and implementation in municipalities, counties and states that enforce building code regulations. The ICC codes are rapidly becoming the “code of choice” for state and local governments that adopt and enforce building code standards.

Validating CO

The change with the greatest impact is the new IRC mandate requiring single-station CO detection in certain new and existing one- and two- family dwellings and townhouses. Detectors must meet Underwriters Laboratories (UL) 2034, the standard requiring single- and multiple-station CO alarms, to be designed to detect elevated levels of CO and sound an alarm when CO reaches a health threatening level. The new code covers newly constructed dwellings within which fuel-fired appliances are installed or have attached garages and existing dwellings that require a permit for remodel within which fuel-fired appliances exist or have attached garages. These new provisions will go into effect with governmental unit adoption of the 2009 edition of the IRC.

It is important to note that even though the 2009 edition of the IRC references single-station CO alarms, it should not prevent UL 2075-listed system-connected CO detectors from being used. This is because UL 2075 system-connected CO detectors are required to have the same alarm thresholds as UL 2034-listed CO alarms and the 2009 edition of NFPA 720 references UL 2075 system-connected CO detectors as acceptable.

Yet, municipalities such as Chicago have had CO mandates for more than a decade. And state laws and local ordinances requiring CO alarms in residences and other dwellings have been enacted in hundreds of communities in 23 states, most recently Michigan and Georgia.
The long lag time is due, in part, to the insufficient technical data to support the mandatory installation of CO alarms. The IRC committee also urged the industry to address the issues of reliability and false positive indications.

Two important documents changed the course of the IRC’s CO detection mandates. First, technical data from a UL study supports the reliability and false alarm immunity of CO alarms. This five-year UL study, CO Alarm Field Study, evaluated the effectiveness of CO alarms. The study concluded that CO alarms provide effective signaling protection when there are dangerous concentrations of CO. In addition, the study demonstrated that CO alarms generally do not emit false alarms in the field.

Second, the 2006 Technical Committee for NFPA 720, Standard for the Installation of Carbon Monoxide (CO) Detection and Warning Equipment, conducted a complete rewrite of the standard in order to keep up with the trend in state legislation requiring the installation of CO detectors. The adoption of the 2009 edition of NFPA 720 provides the industry with a national CO detector installation standard for all buildings, not just dwelling units. NPFA 720 adds credibility to the reliable performance of CO detectors.

Additionally, there are currently 23 states that require the installation of CO detection in dwellings and, in some cases, commercial buildings without any major reliability issues.
The new requirement for CO detectors represents a critical step toward developing these requirements at the state and local levels.

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