Select Page

Devices emitting high frequency noise are often advertised as being able to repel pests via ultrasonic sound. They are, according to their manufacturers, specifically designed to repel, injure or even eradicate pests — such as insects and rodents — completely. However, it should be noted that both testing labs and the US Federal Trade Commission (otherwise known as the FTC) dispute these claims.

As we well know rodents and insects carry disease, and are able to infect humans with serious illnesses. These illnesses can quickly pose a grave threat to our health and to that of our families, communities, and even our pets. Diseases such as dengue fever, Weil’s disease, Salmonella Typhi — which causes Typhoid — and dysentery, are all present in on and around common household pests such as rats, cockroaches and mosquitoes.

Any pest infestation can also be extremely expensive as they can cause significant damage to buildings, such as offices, and even our homes. It extreme cases it can even result in your home having to be condemned and pulled down. Rats and mice can cause electrical fires, numerous kinds of pests can cause unworldly stinks and all amounts of untold harm to a building’s structural integrity and liveability. On identifying droppings or gnawed /chewed surfaces, and/or holes in structural materials such as electrical wiring, flooring or walls, it’s time to admit you have a problem. 

Arguably one of the worst infestations — due to them being so persistent and difficult to get rid of — are cockroaches. Lovers of any kind of slovenly living these most recognisable of unwanted guests will strive to get in at all costs. Once inside they multiply — and keep doing so — doing their very best to stay put. Easily spotted via their droppings that look like specs of ground-pepper — and typically found in dark corners, kitchen cupboards and under the fridge — the makers of ultrasonic pest control devices say these pests are a thing of the past. They market their product as an effective way to keep the army of invasive cockroaches — and those other disease-ridden home destroying pests — away.

It sounds (pardon the pun) like a great way to keep your home, other buildings and workplace free of “The Unwanted”, after all, who doesn’t want to use the easiest and safest method of pest control?

​How Manufacturers Claim They Work

​Using sound to drive out, or even keep pests away, is a surprisingly ancient practice that was widely used by the Chinese. Their inventiveness saw them incorporate numerous kinds of noise making devices to drive off rodent infestations both in crop fields and storehouses, even their own homes and places of work and play. 

However, using sound frequencies beyond the upper limits of human hearing has only been a recent development in our battle against pests; making inroads into this multi-billion industry over the last twenty years or so. The makers of these devices stand by their products and market them as being an effective and less harmful (to the environment) and less dangerous (no poison) way of pest control.

Simply plugged into an electrical outlet the devices are basically left to themselves to get on with the job of deterring or forcing pests to leave due to the uncomfortable experience they have when close to the source of sound. 

The high frequencies involved are meant to trigger a reaction in pests known as an “audio-genic seizure response”. Demonstrated by confused movement with no direction, convulsions, and even death from haemorrhaging, the response looks to discourage, drive away, or even kill the targeted pest. 

The supposed science behind these products is that the confusion caused to the pests sends them on their merry way, as the interference from the ultrasonic sound stops them from sourcing food, breeding, building nests, or even communicating. Not even the hardy cockroach would stick around for long if they couldn’t focus enough to even eat.

There is no doubt that as an accessible product they appeal to consumers, as they are very easy to use — just plug them in — and have no notable effect on humans. Ultrasonic devices are also popular because they completely eliminate the need for traps and poison, which are seen by some as being an inhumane form of pest control — and potentially harmful to the environment and other animals. No one wants to be using a toxic substance that could be possibly consumed by a family pet, or even a curious toddler.

Presently there are also electromagnetic and subsonic devices available for purchase and on doing any kind of research you will find that each manufacturer approaches the devices in their own way, with designs, signal intensity, rate and frequency, all being different.

Once plugged into an outlet a device will emit short wavelength, high-frequency sound waves that we can’t hear. Younger people can hear between 20 to 20,000 Hz, middle-aged people will only catch up to 12-14,000 Hz. Other animals and insects can hear sounds in much higher ranges. On average, ultrasonic devices use sounds within a range of 65,000 Hz, which — according to ultrasonic pest control device manufacturers — sees pests stay away, move away, or die.

We think it’s always worth mentioning how important it is to keep on top of pest control before it is needed. Prevention is always better than cure. Why not do a few things around the home such as sealing gaps, repairing screens and moving your firewood pile further away? Even small things like this can greatly reduce how attractive your home is to unwanted guests.

The Bottom Line: Do They Work?

​Putting it bluntly, the results are a mixed bag. Even after years of investigation there seems to be no authoritative conclusion as to if these devices’ efficacy as an effective pest control approach is worthy of your time, effort or money – even though they last up to five years and don’t need constantly replenishing, how is that useful if they don’t work? 
In 2002 the Kansas State University ran tests and concluded that the devices were successful at deterring insects such as crickets, however, unfortunately, the same product did little to deter our least favourite bug: The cockroach. 

Totally left unaffected by any of the products tested were ants and spiders, so a more traditional, well-established approach would be needed there if you see a need to rid your home or office of these pests. 

Those pests that did initially react to the noise — moving away or reducing activity — soon seemed to realise that the effect was in fact harmless and adjusted accordingly, a kind of fast-forwarded evolution if you like. Yet, it’s important to note that even those products that have scored well under laboratory conditions are probably not going to deliver the same level of effectiveness once placed in a real-world situation, where any signal can be easily blocked or weakened by the surrounding environment through radio and TV signals, walls, and home furnishings.

And it hasn’t all been “totally safe and problem free”. There have been instances where phone conversations on cell phones have dropped in quality, if not completely, home alarms have stopped functioning and hearing aids have been made inoperable. There is also the issue of being exposed to such inaudible sounds 24/7 365 days a year, although as of yet there is no evidence to demonstrate any harmful effects on humans (or pets), is it a good thing to be constantly exposed to? It’s a question worth considering.

Also important to recognize is that manufacturers’ claims of how effective their products are and how they work are unsupported by scientific fact. Many companies have received warnings from the FTC stating that, “Efficacy claims about those products must be supported by scientific evidence.”  As of 2019 at least one company has been sued by the FTC for violating this warning, and if there is one thing we need as consumers it’s that products must do what they claim to do or we will all up buying things that don’t deliver on their promise.

Yet, before we go ahead and build an enclosing wall of doom-and-gloom around these products, it is important to note that some people do swear by them. Those that do see them as effective strongly recommend that you research specific brands before purchasing any ultrasonic pest device, and think about your specific needs. Also, as they report, they really need to be placed in locations where the signal can travel unimpeded. The wider and more open the space you are “treating” with these kinds of devices, the better.

​There Are Better Options

It is easy to find great feedback and positive experience stories about many more reliable forms of pest control, such as pesticides, traps and chemical regimes that are effective.  Even a cat can be a superb way to see mice and cockroaches reduced in numbers – if not disappeared completely. 

Yet, if you have toddlers and babies around, or even pets, chemical exposure is something to which you will be probably be quite rightly anxious about. Perhaps you are even worried about your own personal exposure to dangerous toxins. This concern can be a leading reason to buy an ultrasonic pest control device. Whether you want to repel rodents, insects or wild game, a device — in theory – does exist for you. But do they really accomplish their intended purpose? Our advice would be to ask a professional. 

By asking a qualified inspector what they think of ultrasonic devices we are positive that the answer will pretty much determine how much faith you should put in this kind of approach to pest control. If you do ask for a home inspection, be sure to note as to if the inspector is wearing appropriate clothing. Any inspector worth their salt will always wear the appropriate protective equipment when inspecting areas of a home that can offer shelter to pests. If they rock up in a t-shirt and jeans, it’s time to say “thank you but no thank you” and find a genuine pest control expert.

So, do they work? The manufacturers seem to thing so, but they’re not in the business to undermine their money making machine, yet they say their ultrasonic pest devices reduce household pest infestation. Yet, and here’s where I am more prone to listen, laboratory testing has shown this to not be the case and that the majority of devices do not work as advertised, which is a straight violation of FTC guidelines.  

Our advice would be to tackle pest problems via a qualified inspector, a professional who can help identify a particular pest problem and advise on practical solutions that deliver the desired results: A pest free environment!


Footnote: Please always make sure that any inspector you ask is qualified to perform wood-destroying organism (WDO) inspections, which can further identify and possibly diagnose insect infestation problems to help homeowners devise workable solutions.  This is especially important for those homes that are found in regions where termites/white ants can be found.