Facts
about ultrasonic sound waves
Ultrasonic
sound wave frequencies are above what humans normally can hear
(approx. 20 - 20000 Hz). The Topo Stop models E250 & E500 primarily emit
randomly microprocessed ultrasonic waves in the interval 25000 - 30000 Hz.
Ultrasonic sound waves only affect
the open space/room in which the device is installed and bounce on all hard
surfaces like light reflects in a mirror. Hence ultrasonic
sound waves can not penetrate floor, roof or walls!
From this fact we learn that a device installation
as shown in the animation to the right will not give a satisfactory sound range.
Optimum
location of device
In order to secure a maximum range of ultrasonic sound wave for instance in
a crawling space with a dividing wall as shown to the right, the best location
of the device is as shown in the animation.
Ultrasonic
sound waves do not harm humans or pets
Some people are
worried that ultrasonic sound waves could be harmful to pets and humans but
this is not the case for two reasons.
1) Firstly, in most cases the pest repelling
equipment is for optimizing reasons installed in spaces outside of living quarters
(attic, crawling space below ground floor) and from there the sound waves cannot
affect you at all (physical law!).
2) Secondly, if contrary to our recommendations
a device is being installed in living spaces we are already surrounded by massive
ultrasonic sound waves emitted from fluorescent tubes, TV sets, refrigerator
and other electrical installations. The only report on humans reacting on ultrasonic
sound waves we have heard about is one where fluorescent tubes with a too low
ultrasonic sound emission value (approx. 60000 Hz) with some people caused headache.