The Green Car Integrity Project is a grassroots effort to address unnecessary vehicle noise and its impact on individuals and communities, public health, and the environment. Our focus is a letter-writing campaign. Our goal is to foster respectful, constructive communication with industry leaders in order to reduce intrusive, discordant horn sounds in our communities.

In residential areas throughout North America, random horn sounds are a constant backdrop as car owners "confirm" that they have locked their cars. The horn sound is currently factory installed as audible security confirmation in more than half
of all vehicles manufactured for sale in the US and Canada. At the same time, most cars feature a high-decibel "Panic Alarm" whose use as a security feature has never been proven, and many key fobs and phone apps use a horn honk to locate
a "lost" car in a parking lot. Horn sounds are also used to signal mundane events such as remote start, electric charging, and a key being left in a car.

By contrast, most vehicles manufactured for sale in Europe feature visual rather than audible lock confirmation, and remote keys do not feature "panic alarm" or "car finder." Automakers explain this difference by referencing European countries' stricter federal noise regulations. While the EPA does not currently fund its Office of Noise Abatement and Control (ONAC), there are laws on the books in nearly every state in the US that limit horn use to emergency situations. Using a horn for acoustic alert clearly saves money on having to use a second sound source, but automakers who opt to use a horn sound choose to use a sound that does not comply with a basic safety standard.

Some automakers have never used a horn sound for audible confirmation, and some have always used flashing lights.
Others, such as Toyota and Subaru, transitioned to a subtle, non-intrusive electronic tone more than a decade ago. Currently Honda, Nissan, and Hyundai are transitioning from a horn-based alert to the electronic tone. What are other automakers waiting for?

Every automaker currently using a horn sound for security confirmation should make the transition to a subtle, low-decibel electronic chirp with every model, with a default option of visual confirmation only. Every automaker should eliminate all use of horn sounds for car finding and signaling of mundane situations.

Peace and quiet have become a luxury in North America. Access to quiet, which is so essential to human health, is a rarity that only the affluent are able to experience on a consistent basis. Automakers who are fully committed to environmental sustainability ideally should manufacture all of their cars using European noise standards, or at least replace the horn sound with a low-decibel, non-irritating electronic tone in every car manufactured for sale in North America.