Carbon Monoxide and Portable Generators – Unregulated Products with a Long History of Harm
Injured by carbon monoxide poisoning caused by portable generators? Contact a Houston portable generator carbon monoxide poisoning lawyer to get the compensation you deserve.
A complaint was filed against Honda in 2025 concerning its generators. View the complaint.
The Silent Killer
Carbon monoxide (CO) is a colorless, tasteless, odorless, non-irritating toxic gas produced as a by-product of the incomplete combustion of carbon-based substances. Its sources include any fuel-burning product: car, truck, or boat engines, gasoline-powered tools, such as pressure washers and compressors, stoves, lanterns, grills, fireplaces, gas ranges, furnaces, and portable generators.
When inhaled, CO is absorbed via the lungs into the bloodstream, where it binds to the hemoglobin with an affinity of more than 200 times that of oxygen. Those tight bonds impair the blood’s capacity to carry oxygen, resulting in inadequate blood supply to the body’s tissues and organs, especially the heart muscles.
Known as the “Silent” or “Invisible” Killer, CO is the most common lethal poison worldwide. According to the Centers for Disease Control, each year, more than 400 people in the U.S. die from unintentional CO poisoning not linked to fires. CO poisoning sends more than 100,000 people annually to the emergency room, with more than 14,000 hospitalized. A study published in October 2023 in Lancet Public Health found that such deaths are on the rise here. An international consortium of researchers analyzing global death certificate data documented that unintentional CO deaths fell worldwide by 53.5 percent from 2000 to 2021, but rose by 30.4 percent in North America.
Consequences of CO poisoning
CO poisoning can produce long-term neurologic effects, depending on the level of exposure, its duration, age of the victim, and other underlying health risk factors, such as chronic heart disease, anemia, or respiratory conditions. CO poisoning’s initial symptoms can vary widely, including headache, fatigue or generalized weakness, dizziness, nausea, and vomiting. With more severe exposure, these symptoms can elevate to confusion and trouble thinking, loss of consciousness, ataxia, seizure, coma, disorientation, and cognitive difficulties.
Almost half of the people exposed to CO develop delayed neuro-psychological consequences that can be disabling and sometimes permanent. These effects can surface days or weeks after exposure and include disorientation, cognitive difficulties, judgment, memory, and concentration deficits, personality changes, tinnitus, central hearing loss, nystagmus (involuntary eye movement), and other visual disturbances, gait and motor disturbances, peripheral and cranial neuropathies, psychosis, dementia, and Parkinsonism.
The Problem of Portable Generators
Portable generators are a particularly deadly source of carbon monoxide. One portable generator can produce as much CO as hundreds of idling passenger cars. When portable generators are placed in an enclosed space such as a garage, basement, or living area, or in close proximity to a living space, such as by an open window, the CO can rapidly accumulate “to dangerous or fatal concentrations within minutes,” according to the National Institute of Occupational Health and Safety.
Occupational health experts have set safe levels of CO concentration (measured in parts per million (ppm) of air) at 25 ppm; exposure to levels above 150 to 200 ppm can cause disorientation, unconsciousness, and death. Tests of portable generator emissions in enclosed spaces show that the output of some generators can reach 1,000 ppms.
Carbon Monoxide Statistics
In February 2024, the U.S. Consumer Product Safety Commission (CPSC) estimated that about 100 people die each year from carbon monoxide poisoning associated with portable generators. CPSC’s study also found that among those fatal incidents, the top reasons for using a generator were weather-related power outages, power shutoffs, and powering temporary locations, such as cabins or campers.
In 2023, the CPSC released a report covering deaths and injuries that occurred between 2012 and 2022. It found that 77 percent of the 553 generator-related CO fatalities occurred when the generator was placed inside the living area of the home; in 66 percent of these fatalities, where information was available, there was no attempt to provide ventilation. Another 5 percent of fatalities occurred when the generator was outdoors, but too close to windows, air conditioners, or other places that allowed the CO to enter the home, or placed outside of the living quarters, but in an enclosed space, such as the hallway of an apartment building or a garage.
Attitudes Towards Portable Generators
In 2024, UL, the international voluntary safety standards-setting company, published a study entitled Understanding the Silent Threat: Early Detection and Prevention of Carbon Monoxide Poisoning showing that the majority of the estimated 29 million U.S. generator owners do not feel at risk — or even know there is one:
One in five (23%) owners did not even realize that portable generators are a potential source of CO. Four in ten owners (41%) are not concerned that they will be exposed to CO from their portable generators, and nearly two-thirds (62%) do not feel that they or their households are at risk of CO exposure or poisoning from their generators…29% of generator owners mistakenly believe it’s safe to operate a generator in the garage with the door open, while another quarter (25%) don’t feel it’s necessary to keep portable generators at least 20 feet from people and pets. Even more concerning, 23% are under the misconception that a carbon monoxide detector is unnecessary when running a portable generator.
The reasons some consumers place a portable generator in unsafe locations range from wanting to protect it from inclement weather to ignorance about the potential for injury and death. Research studies going back two decades consistently show that most people have a very rudimentary knowledge about carbon monoxide. While they may understand that it is a hazard, they know little else about how to recognize the symptoms of exposure, possible sources of CO, how to protect themselves, and how to ensure proper ventilation.
Public health investigators have examined the question of CO knowledge, attitudes, and practices regarding and have found that a significant portion of the public is unaware of how to safely use and locate portable generators. Researchers have also studied these issues in relation to demographics and found that in lower-income and immigrant communities, knowledge about the CO danger and prevention is lacking.
Deadly But Unregulated
Despite these serious risks and their long record of harm, portable generators remain unregulated for CO safety.
There are two voluntary standards to which manufacturers can choose to design and manufacture their portable generators. These are written by industry representatives and approved by a consensus of participating companies or trade association members, with non-binding suggestions from the U.S. Consumer Product Safety Commission (CPSC). Both were published in 2018.
UL Standard (ANSI/UL 2201)
The UL standard, ANSI/UL 2201 – Carbon Monoxide (CO) Emission Rate of Portable Generators, requires a reduction in CO emissions, but it allows the manufacturer to achieve this by any “widely available and proven technologies already in the marketplace, such as electronic fuel injection (EFI), an onboard electronic engine management system.” Another important provision requires portable generators to incorporate shutoff technology so that if a generator is used in an enclosed space, sensors detect the build-up of CO and shut it off.
PGMA Standard (ANSI/PGMA G300-2018)
The Portable Generator Manufacturers Association also established a voluntary standard, G300 Safety and Performance standard (ANSI/PGMA G300-2018). It simply requires portable generators to be equipped with carbon monoxide sensing technology and an auto-shutdown feature. It went into effect in late March 2020.
Lack of Federal Regulation by the CPSC
The CPSC, which has the federal authority to write a regulation requiring that portable generator manufacturers design and manufacture their products to eliminate or mitigate the CO hazard, has not yet established mandatory performance requirements for portable generators. It began tracking injuries and deaths in the early 2000s. The agency initially focused on improving the warning labels on portable generators, after a survey found that most provided vague, inconsistent, and incomplete information in English only.
2007 Warning Standard
In 2005, seven major hurricanes, including Category 5 Katrina, made landfall, most of them in the U.S. The successive waves of weather-related devastation prompted the CPSC to establish a warning standard in 2007. The rule required the warning label to add pictograms and to state: “Using a generator indoors CAN KILL YOU IN MINUTES.”, “Generator exhaust contains carbon monoxide. This is a poison you cannot see or smell.”, “NEVER use inside a home or garage, EVEN IF doors and windows are open.”, and “Only use OUTSIDE and far away from windows, doors, and vents.”
The new warning requirements failed to reduce the CO injury and death toll associated with portable generators. In fact, despite warning language to NEVER use a generator in a home or garage, more consumers are doing so after the labeling requirements went into effect than before the capital letters and pictograms were mandated.
Proposed CPSC Regulations
The CPSC also started, in 2006, the process of writing a mandatory regulation for portable generators to prevent CO poisoning, shock/electrocution, fire, and thermal contact burns. Among the options the agency wanted to explore were the feasibility of performance requirements to reduce the generator engine’s CO emission rate, or for systems that use CO sensors and shut-off technology.
After a decade of CO research, such as studies on the accumulation of carbon monoxide in enclosed spaces, and the development of a low-CO-emitting generator prototype, the CPSC proposed to set emissions standards for portable generators. The announcement cited the increase in portable generator deaths. As of May 2015, the commission had tallied at least 751 generator-related CO poisoning deaths that occurred from 2004 through 2014, along with 8,703 CO injuries seen in emergency departments.
Failure of the 2007 Warning Strategy
The CPSC also admitted that the 2007 warning strategy was a failure, because “deaths and injuries from the improper placement of newly purchased generators suggest that at least some consumers poorly understand and process the information contained in the operating instructions and warning labels and consequently, these consumers continue to put themselves and others at risk through the improper placement of generators in enclosed areas.”
At the time, the CPSC did not consider a requirement for a CO-sensing and automatic shutdown feature because it doubted the reliability and effectiveness of the sensing technology for remotely located CO-sensing devices and generator-mounted sensors.
Proposed CPSC 2023 Mandatory Standards
In April 2023, the CPSC resumed its effort to create a mandatory standard. The commission found that a combination of the UL and PGMA voluntary standards was more likely to be more successful in reducing the risk of CO injuries and deaths. Specifically, the incident and the simulation data showed that the CO shut-off requirement of the PGMA standard would need to be combined with the emissions requirements of the UL standard because “an effective shutoff system alone is not sufficient to protect consumers from death and serious injury from accumulated CO.” The CPSC also decided to write a regulation because its survey of available portable generators that adhered to either of the voluntary standards showed that the industry had been slow to implement CO mitigation technology into its retail products.
Arguments Against Mandatory Standards
Engine manufacturers have fought hard against any mandatory rule, in particular, the requirement to build portable generators with lower CO emissions. The PGMA, which represents all of the major portable generator manufacturers, has argued that only the U.S. Environmental Protection Agency has the authority to regulate emissions.
They also maintain that a CO detector and engine shutdown mechanism was the low-cost, efficient, and feasible strategy to reduce CO injuries and deaths associated with portable generator emissions. Further, emission reduction designs will cause the generator itself to reach excessive temperatures, creating a contact burn and fire hazard, it has been argued.
This protracted battle with industry over an emission standard continues today. The PGMA and its member companies have vigorously petitioned against it, using various strategies and partners, including Republican appointees in the Trump administration.
Alternative Generator Designs
Manufacturers and regulatory agencies have been working on mitigating or nearly eliminating carbon monoxide hazards in gasoline-powered machines for half a century. In motor vehicles, the advent of the catalytic converter, required in all new vehicles since 1975, greatly reduced CO emissions from that source. In the marine environment, low-CO emission generators have been commercially available since 2004.
That year, Westerbeke a major manufacturer of gasoline-and diesel-powered generators for boats launched the “Safe-CO™” series of gasoline-generators which, for the first time, reduced CO emissions by 99 percent using “patented engineering” and electronic fuel injection. The following year, Kohler Power Systems (now Rehlko) unveiled a new line of marine generators that used a computer-controlled engine and EFI and also claimed a 99 percent reduction in CO emissions. Indmar Products Company is the first manufacturer of a propulsion engine with catalytic technology, resulting in low CO emissions. The efficacy of these generators was assessed by the U.S. Coast Guard, the Centers for Disease Control, NIOSH, and the California Air Resources Board.
Working with the CPSC
Similarly, the CPSC has been working with manufacturers, researchers, and the standards-setting entities since 2006 on alternative designs for portable generators in pursuit of low-CO-emitting and automatic engine shutdown technologies. Some of this work was built on the engine design advances and standards for automotive and marine generator engines, catalytic converters, and fuel injection.
The CPSC staff conducted experiments, coupled with computer modeling, to determine at what rate the CO emissions of a 5.5 kW generator running in the basement would produce life-threatening levels to occupants in the living spaces. Additionally, the CPSC produced another demonstration project to show that an engine with a substantially reduced CO emission rate could reduce the risk of fatal and severe CO poisoning when used in an indoor location, delaying the onset of CO poisoning symptoms and slowing their worsening, so that occupants have time to recognize their exposure and exit the building. The CPSC staff also participated in a demonstration project to develop a generator with a remotely mounted CO-sensing device and an automatic engine shut-off.
Advancement to Portable Generators
In contrast to marine engine manufacturers, the portable generator industry would lag a CO safety strategy by 14 years. In 2016 Nett Technologies, offered the BlueCAT™ emission control system, which could be fitted to commercially available Small Spark Ignited (SSI) engines used in portable generators. It claimed to reduce CO by up to 98 percent, and oxides of nitrogen (NOx) and hydrocarbons by up to 95 percent. In 2016, Techtronic Industries presented the CPSC with its low-emissions portable generator, and the following year, it became the first company in the industry to offer such a design commercially.
Ryobi followed with a low-CO-emitting portable generator in 2018. The first portable generators with CO sensing and automatic shut-off systems were offered by Briggs & Stratton (CO Guard) and Generac (CO Sense) in 2018. In the years since, other manufacturers have introduced models with a similar design.
Lack of Compliance with Standards
In 2021 and 2022, CPSC staff surveyed manufacturers’ production of generators that were compliant with the UL or PGMA voluntary standard and found that only a handful of companies had achieved substantial compliance with the UL or PGMA standard. The staff estimated that there was a 30 percent compliance rate with the PGMA standard; one-sixth of those were estimated to also be compliant with the emissions requirements of the UL 2201 standard.
The commission concluded that this market analysis, combined with the “unabated” number of CO-poisoning incidents, showed that not enough CO-safe generators were being sold to significantly reduce the risk of injury and death from portable generators.
While new generations of portable generators may be built to either the UL or PGMA voluntary standards, there is no guarantee of widespread industry adoption. And regardless of the availability of technological solutions and the rising toll of CO injuries and deaths, there are no government-mandated performance requirements for portable generators.
In the meantime, there are many millions of generators still in use in American homes and at job sites that have no CO-mitigation features at all. This combination makes it likely that consumers will continue to bear the brunt of this long history of federal and industry inaction.
Contact Williams Hart & Boundas, LLP for a Consultation
If you suffered from carbon monoxide exposure or lost a loved one as a result of CO poisoning that was caused by a portable generator, contact Williams Hart & Boundas, LLP. Our experienced Houston portable generator carbon monoxide poisoning lawyers can help you hold the generator’s manufacturer accountable for the losses you and your family have sustained. To learn more about your legal options, reach out to our team of lawyers at (713) 230-2200 or contact us online to schedule a free consultation.