Keyless car ignitions — where the driver just pushes a button to start the car — is very convenient. But can it be dangerous. This article says that "at least 60 U.S. drivers … have parked cars with keyless ignitions in their garages, only to forget to push a button and turn the vehicles off." That can cause deadly exhaust to seep into a car owner's homes. So,"[s]afety advocates and survivors … think the solution would be requiring car makers to install an alarm or software that kills the ignition after time has lapsed." Federal regulators have proposed a rule that would require an audible alert but not an automatic shutoff.