San Francisco & New York – When fire threatens, every second matters. That’s why Watch Duty, the real-time wildfire alert service, partnered with Sixième Son, a global sonic branding agency, to create the audio alert that notifies the public of threats to life or property. Reaching more than 15 million active users across 22 states in the U.S. Northwest, Southwest and Central regions, Watch Duty is the go-to app for people in fire-related emergencies.
“Sound can carry information more quickly than text or visuals, especially in moments of stress. Our goal was not to create frightening sounds, but instead, create clear, firm, and human sonic cues that people instinctively recognize and comprehend,” explains Daina Todorovic, Chief Client Officer US at Sixième Son. “Sixième Son’s expertise in sonic identity has been put in the service of the public good here. By combining design methodology with empathy, the team shaped a soundscape that guides people through fear, preparation, and relief.”
The Watch Duty alert was intentionally designed to be organic in quality and not overly synthetic. Inspired by the sound of a drop of water, the alert is intended to not only break through everyday device noise, but also to reassure and guide communities in moments of crisis.
Unlike traditional phone alerts, which often go unheard or ignored due to “notification fatigue,” Watch Duty’s sound cuts through with distinct tonalities, around 1000 Hz (close to a human voice frequency), optimized for mobile devices.
“Every sound tells a story,” said Watch Duty CEO John Mills. “By working with Sixième Son, we ensure app users receive critical information with clarity, humanity, and trust. These sounds aren’t just alerts, they’re lifelines.”
Watch Duty’s Numbers So Far:
- Watch Duty reached 7.2 million yearly active users in 2024;
- Watch Duty was named in the 2025 TIME100 Most Influential Companies list and ranked as the #1 NGO in 2025 by Fast Company;
- During the Palisades and Eaton fires in January 2025, the app gained 1.4 million new users in just 48 hours, and was widely credited with being a critical lifeline in Los Angeles; and
- The app community now spans 22 wildfire-prone states.
Next, a new, calmer sound will be added to the app’s alerting system. It will be recognizable to Watch Duty users as a cousin of the original tone. The new tone signifies the need to be watchful, when there is still time to prepare for danger, such as a flood or storm.
As climate change increases the frequency and severity of natural disasters, sound is proving to be one of the most inclusive, accessible tools we have: heard instantly across language barriers, reliable even when screens can’t be checked, and powerful enough to wake us when it matters most.
CREDITS
- Founder & President: Michael Boumendil
- US Managing Director: Colleen Fahey
- Chief Client Officer US: Daina Todorovic
- Creative Director: Vincent Turbé
- Artistic Director: Alice Lépine
- Senior UX Designer: Alexis Mangou
ABOUT SIXIÈME SON
Sixième Son is a global sonic branding agency that creates long-lasting sonic identities, designs sonic signals, and provides soundscapes for environmental brand experiences. We have developed 500 sonic identities for brands worldwide. We aim to increase brand value by differentiating each brand, calling attention to it, conveying its values, and making it memorable and successful through sound. Our offices are located in New York, Toronto, Paris, Singapore, and Madrid. Sixième Son operates across all sectors, serving both B2B and B2C clients. Over 2 billion people worldwide hear at least one Sixième Son creation daily.
