A modern-day vape detector can operate on battery power

https://www.benzinga.com/pressreleases/26/04/g52007204/zeptive-releases-update-1-33-500-for-vape-detectors-adds-enhanced-detection-performance-loitering-

A modern-day vape detector can run on battery power, making it possible for flexible placement in washrooms and locker rooms without costly circuitry or restorations.