Carbon Monoxide: A Step Backwards

Recently proposed federal legislation (HR 1796) will require that carbon monoxide (CO) alarms be U.L. 2034 listed to be sold in the U.S. California just recently passed a similar law. These well-intentioned legislators don't realize they are inadvertently attempting to close the door on the only devices that truly protect people of all ages and health conditions: low-level CO monitors.

The reason low-level CO monitors don't meet UL 2034 is because the standard was written to protect "normal, healthy adults" from conditions that could lead to severe acute illness or immediate death. The standard's lowest acceptable alarm levels allow ongoing, chronic exposure to CO levels under 70 ppm (parts per million) indefinitely. There's a ton of scientific evidence that long-term exposure to concentrations as low as 15 ppm can lead to a multitude of illnesses and diseases.

Some Statistics: Here are just a few facts published by leading CO poisoning expert, Dr. David G. Penney, Ph.D. on his website, Annually in the U.S., tens of thousands of people seek medical attention or lose several days, weeks, and even months of normal activity from CO exposure. Each year there are over 40,000 emergency department visits for CO poisoning. Furthermore, more than 450 people die through unintentional CO exposure, according to the U.S. Center for Disease Control.

Petty adds that, "an emerging body of evidence suggests longer exposures to lower levels of CO, ie. chronic CO poisoning, are capable of producing myriad debilitating residual effects that may continue for days, weeks, months, and even years."

A paper by The Mayo Clinic reports that a study done in a southwest U.S. hospital indicated that 20% of patients seeking aid for chronic flu symptoms were found to have elevated levels of carbon monoxide.

How Do You Protect Your Customers? Currently only two manufacturers — National Safety Institute (NSI) and CO Experts — offer low-level CO monitors. These devices measure concentrations as low as 5 ppm with great accuracy and alarm at levels of 15 ppm or less. Both products are superior to most of the alarms on the market, as they use electrochemical sensors, which are much more accurate and reliable than the semiconductor sensors prevalent in store bought UL alarms.

NSI is changing its labeling to reflect the fact that the product is a "monitor," not a UL-listed alarm or detector, and it should be used in addition to a legally required alarm in a residential application. This language should be sufficient to allow contractors to continue to sell these important health and life saving devices.

These monitors are typically available through trained contractor resellers and should be installed in addition to a UL 2034 listed alarm. Unfortunately, most consumers are ignorant about the dangerous levels that UL listed alarms allow, thinking that the government has the knowledge to keep their families safe. Unless educated by a trained seller of low-level CO monitors, the average consumer may never know of the dangers — until it's too late.

A History Lesson: Nearly two decades ago, allowable CO alarm levels from UL listed devices were much lower, with alarms sounding at levels as low as 30 ppm. There were also low-level alarms made by several manufacturers that detected levels as low as 15 PPM. Unfortunately utilities and fire departments were getting so many CO calls they deemed as "false alarms," that they lobbied manufacturers, and subsequently Underwriters Laboratories, to increase minimum levels at which alarms would go off. Neither of these public entities had the instrumentation nor the training to detect or diagnose low-level emissions. It's interesting though, that firefighters are required to wear breathing apparatus at CO levels above 30 ppm.

Ironically, the very people who we rely on to safeguard us when it comes to CO poisoning are actually responsible for tens of thousands of low-level CO poisonings over the last 10-plus years, as they convinced UL to raise the minimum alarm levels to 70 ppm for up to four hours.

What Can You Do? As an HVAC contractor you're in the best position to provide additional protection to your customers. This can be enhanced through consumer education, and by educating yourself on the dangers of carbon monoxide, how to measure it, and how to test your customers' homes for conditions that lead to CO emissions. If you haven't already, be sure to get your field personnel trained and certified so you can help keep your customers' families safe, and provide the best possible level of protection available to safeguard them when you're not there to.

Dominick Guarino is Chairman & CEO of National Comfort Institute (NCI), (, an international training, certification and membership organization with nearly 500 contractor members. NCI coined the term, Performance-Based Contracting™ to describe what their members do. The organization’s primary mission is to help contractors grow and become more profitable. Email him at [email protected].

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