Some children and young adults (and some older adults too) can hear 'ultrasonic' cat deterrents. We think that the noise they emit is loud, uncomfortable, and constant. We think it violates people's right to a quiet enjoyment of their home.
You may be interested in these active petitions
The devices can emit high-frequency sounds, varying in pitch, 24/7. If you live near one and can hear the sound, it can really impact your wellbeing. The noise can be difficult to locate so talking to the owner or submitting a noise complaint can often not be an option.
If the noise was audible to everyone, we think it would be clear that it is not an appropriate or social way of deterring cats. We think they are a noise nuisance and should be banned.