Carbon monoxide from vehicles is claimed to kill 200 people per year in the US, prompting environmental engineer Albert Donnay to petition NHTSA for a requirement to address the issue. The organization turned down his request this week, stating that a device to shut down the engine of a stationary vehicle when dangerous levels of CO are detected would not prevent most of those deaths. While accidental deaths were the primary focus, it's also acknowledged that the decision of some to take their own lives with automobile exhaust prompted Donnay to file the request. The whole problem with this idea, as well intended as it may be, is that such a device would only be fitted to brand-new vehicles. A modern vehicle doesn't really produce a whole lot of CO, so I'm not sure that it's that harmful if properly maintained (I recall hearing that the Hemlock Society says that CO poisoning from cars is no longer a reliable means of suicide, but you'll have to forgive me for not researching this further). Older vehicles can definitely kill in a short amount of time, but of course those wouldn't be fitted with such devices. NHTSA suggests a home CO detector, and that's definitely a worthwhile addition to any garage, or inside the home near any garage service doors.