Ultrasonic Emissions in Pest-X-Repel Electronic Repellers
The use of ultrasound emissions as a means of pest control is rooted in the difference between the audible spectrums of humans and rodents. For humans the audible spectrum ranges from around 20Hz to 20kHz (contingent on multiple factors such as gender, age and etc.). Sounds below and above these thresholds are respectively referred to as ‘infrasound’, and ultrasound’, and are inaudible to humans. For rodents the spectrum is different, but the principle is identical. Sounds are audible if they fall approximately between 250 Hz and 80 kHz, with the greatest sensitivity occurring between 8 kHz and 38 kHz.
The technological premise of Pest-X-Repel ultrasound rodent repellers, such as the PR-300.2 or PR-220.6, is that sounds with frequencies above the human audible spectrum, but within the rodent audible spectrum, could be used as a means of deterring unwanted rodents without causing discomfort to people. This makes them a very good solution for occupied spaces, such as homes, offices, factories or storage facilities, where rodent infestations often occur.
How Pest-X-Repel Ultrasonic Repellers Operate
The emissions of the repeller are set to oscillate randomly within a strictly defined interval (between 20kHz and 30kHz) and confined to a certain sound pressure level (<120 dB), they are not harmful or even noticeable to humans. However, many scientific studies (e.g. Greaves, J. H., and F. P. Rowe. 1969) have found that emissions with these parameters disrupt the feeding and breeding cycles of rodents, as well as the communication between them. What is more, the randomised nature of the ultrasonic frequencies prevents rodents from becoming used to them (i.e. habituating), which ensures the long-term effectiveness of the unit.
The experiments, that these studies are generally based on, include monitoring the behaviour and vital functions of rodents exposed to the repeller against those of a control group. The trials conducted for Pest-X-Repel repellers featured the same experiments and found that the products had a significant and consistent influence on rodents.
The specific effects that Pest-X-Repel ultrasonic repellers have elicited in rodents during laboratory trials include lethargy, sharp fur, shivering, loss of weight, and in more severe cases, digestion problems and disorientation. The experimental setting for the trials was specifically constructed to mirror field operation of the devices, which reliably confirms that the same effects are to be observed during normal use. Furthermore, due to the randomised times and frequencies of emissions, rodents exhibited no signs of habituation to our technology, making for a long-term and dependable protection of control areas in the field. None of the animals used for the trials were harmed.
Installation & Domestic Hygiene
When used in the field, the ultrasonic repeller poses a trade-off for rodents. The discomfort created by the device is ‘weighed against’ the favourable conditions provided by the environment such as shelter and food. In other words, whether rodents choose to flee or settle in a control area depends on how strong their incentive is to remain. This has several important implications for the use of electronic pest control in treating rodent infestations.
One key takeaway is the importance of good housekeeping and its correlation to device effectiveness. More specifically, this refers to the idea of making the control space a less desirable environment by enforcing good hygiene, removing any organic waste and keeping storage areas tidy (especially those out of reach and not frequently visited). Restricting access to food and shelter makes it more difficult for pests to settle in the control space and create feeding/breeding patterns.
Furthermore, it is important to note the role of placement in the effectiveness of the device. Ultrasound waves disperse outward and cannot travel through solid surfaces, which makes ultrasound repellers a good single-room solution for pests out in the open. However, they will not have the same influence on pests within their lairs, which often are often inside the walls or behind other solid surfaces. For this reason we recommend selecting the appropriate mix of products based on the characteristics of your control area or considering a combined action unit such as the PR-500.3. Lastly, it is important to note that ultrasound is also absorbed by soft furnishings such as carpets, drapes and other textiles, so it is strongly advisable to make sure that the emissions of the device are not obstructed.