NEW YORK (NYTIMES) - It seems like a common convenience in a digital age: a car that can be powered on and off with the push of a button, rather than the mechanical turning of a key. But it is a convenience that can have a deadly effect.
On a summer morning last year, Fred Schaub drove his Toyota RAV4 into the garage attached to his Florida home and went into the house with the wireless key fob, evidently believing the car was shut off. Twenty-nine hours later, he was found dead, overcome with carbon monoxide that flooded his home while he slept.
"After 75 years of driving, my father thought that when he took the key with him when he left the car, the car would be off," said Schaub's son Doug.
Schaub is among more than two dozen people killed by carbon monoxide nationwide since 2006 after a keyless-ignition vehicle was inadvertently left running in a garage. Dozens of others have been injured, some left with brain damage.
Keyless ignitions are now standard in over half of the 17 million new vehicles sold annually in the United States, according to the auto information website Edmunds.
Rather than a physical key, drivers carry a fob that transmits a radio signal, and as long as the fob is present, a car can be started with the touch of a button.
But weaned from the habit of turning and removing a key to shut off the motor, drivers - particularly older ones - can be lulled by newer, quieter engines into mistakenly thinking that it has stopped running.
Seven years ago, the world's leading automotive standards group, the Society of Automotive Engineers, called for features like a series of beeps to alert drivers that cars were still running without the key fob in or near the car, and in some cases to shut the engine off automatically.
The National Highway Traffic Safety Administration (NHTSA) proposed a federal regulation based on that idea, a software change that it said could be accomplished for pennies per vehicle.
In the face of auto industry opposition, the agency let the plan languish, though it says a rule is still under consideration.
For now, regulators say they are relying on carmakers to incorporate such warning features voluntarily.
But a survey of 17 car companies by The New York Times found that while some automakers go beyond the features recommended by the standards group, others fall short.
Safety measures have been a matter of contention among automakers, sometimes even internally.
Toyota, for example, has a system of three audible signals outside the car, and one inside, to alert drivers getting out of a vehicle that the motor is still running.
But when Toyota engineers determined that more effective warning signals were needed - like flashing lights or a unique tone - the company rejected the recommendation, according to testimony in a wrongful-death suit.
Toyota models, including Lexus, have figured in almost half of the carbon monoxide fatalities and injuries identified by The Times.
Toyota says its keyless ignition system "meets or exceeds all relevant federal safety standards".
Some automakers have designed newer models that alert drivers more insistently when the engine is left running - or that shut it off after a certain period.
Ford's keyless vehicles now have a feature that automatically turns off the engine after 30 minutes of idling if the key fob is not in the vehicle, the company said recently.
But many older vehicles have not been retrofitted to reduce the hazard, despite the modest expense of doing so.
It cost General Motors US$5 (S$6.70) per car to install the automatic shut-off in a 2015 recall, according to a GM report to the safety agency.
Regulations require automakers to address other hazards associated with keyless vehicles - theft and rollaways - and those measures might also reduce the carbon monoxide danger.
But the safety agency has found shortcomings and inconsistencies by automakers in meeting those rules.
A Florida fire chief saw so many cases that he took to handing out carbon monoxide detectors.
And litigation against the companies is mounting.
"We're going to continue to see deaths and injuries," said Sean Kane, founder of Safety Research and Strategies, an auto safety research group. "And the manufacturers will continue to settle cases."
The exact number of deaths related to carbon monoxide from keyless-ignition vehicles left running is unknown, as no federal agency keeps comprehensive records.
Through 2016, the most recent year for which data is available, the safety agency had investigated only four fatal incidents.
From news reports, lawsuits, police and fire records and incidents tracked by advocacy groups, The Times has identified 28 deaths and 45 injuries since 2006, but the figures could be higher.
A RISK DETECTED EARLY
The Society of Automotive Engineers' recommendations, issued in January 2011, called on carmakers to install an "externally audible or visual alert" - implying an unspecified number of beeps, or a warning light - when all doors are closed, the key fob is not present and the engine is still running. If the engine automatically shuts off, the alerts are not necessary.
The same year, the traffic safety administration proposed a key fob rule that would require car manufacturers to provide additional internal and external warning beeps.
In addition to protecting against rollaways, it said this would reduce "incidents of carbon monoxide poisoning".
Although it made no provision for an auto-shutoff function - an option that the Society of Automotive Engineers cited - the agency said its own proposal would be "more enforceable".
Compliance would cost the industry less than US$500,000 a year in software coding for millions of keyless vehicles,the traffic safety administration said.
The auto industry opposed the proposal, and a trade group asserted that the regulator's use of vehicle owners' questionnaires to compile a database of defects did not meet the evidence standards of federal vehicle-safety law.
The traffic safety administration released a video two years ago that highlighted the risks of keyless vehicles, including carbon monoxide poisoning.
But the agency has postponed adoption of the keyless ignition regulation three times, and in the meantime at least 21 people have died.
"Once NHTSA has finished its review and determined the best path forward, NHTSA will take appropriate action," the agency said in a statement in March.
'NO ADEQUATE PUNISHMENT'
With no standard in place for alerts or other features that would address the problems of keyless vehicles left running in confined spaces, the traffic safety administration has said repeatedly that it is convinced that automakers intend to meet the Society of Automotive Engineers' recommended practices. And some do.
But it can be difficult to determine with precision what measures automakers have taken on their own.
"You can't trust car corporations to police themselves," said John Uustal, a Florida-based lawyer involved in two keyless ignition cases. "There's no adequate punishment."
At one point, the traffic safety administration appeared to start taking a keener interest in the hazards. It undertook an investigation of seven automakers in 2013-14, conducting tests and asking for documentation of their safety features for keyless vehicles. But the inquiry was quickly and inconclusively wound down.
In a statement in March, the agency said it was evaluating comments on the proposed rule and the data for carbon monoxide deaths and injuries.
In the meantime, in a society increasingly growing older, the hazard is likely to be compounded by demographics.
At the funeral of Fred Schaub, his family said farewell while he lay in the coffin wearing a New York Police Department hat from his detective years. It partly covered the rash on his head.
"My dad isn't going to be the last one who passes away from this," Doug Schaub said.