pest reject side effects

See, High-intensity acoustics for military nonlethal applications: a lack of useful systems. Most people are under the impression that if they dont see a mouse, there is no reason to worry about it. Try to target pests in specific areas such as attics, pantries, kitchens, basements or sheds, ensuring that most of the area is covered. Relationship between detecting pitch via bone-conducted ultrasound and eigenfrequencies of human head, Perception mechanisms of bone-conducted ultrasound assessed by acoustic characteristics in the external auditory meatus, Bone-conducted ultrasonic hearing assessed by tympanic membrane vibration in living human beings, Experimental measurement of tympanic membrane response for finite element model validation of a human middle ear, What middle ear parameters tell about impedance matching and high frequency hearing. In 1990, Smith [136] called for Trading Standards policing following trials showing no effect on deterring birds when ultrasonic devices were placed within a building; and in 2001, a warning was issued by the Federal Trade Commission's Division of Enforcement on the effectiveness of ultrasonic rodent and insect repellents [137]. See appendix A for details on instrumentation. Ultrasonic noise exposure first became an issue in the 1940s, when ultrasonic sickness was thought by many (probably erroneously [45]) to be caused by the advent of the jet engine [14],[92][94]. The range includes symptoms such as a continuous ringing sound in the ears, dizziness, nausea, headaches, migraines, insomnia, vomiting, fainting, and more. The smartphone or tablet is a convenient and inexpensive method of immediately testing for the presence of ultrasound, although it comes with many limitations (e.g. A group of scientists from the Acoustical Society of America conducted a study about the effects of exposure to an ultrasonic rodent repellent device. Parrack could little imagine that the 20 years of uncertainty to which he referred would extend to 70 years by 2015. These devices are small, compact, aesthetically pleasing, and dont take too much space. 2000. The same paper also contains values for Bulgaria (1979) that resemble the levels for USSR (1975) but the author could not identify the original source and so the Bulgaria (1979) levels are not included in figure 3. Four curves are shown, for stated frequencies that are at the centre of the third-octave band over which the measurement was made (at 1 degree angular resolution) in the free field chamber of the NPL in Teddington. Category 3 systems range from automated door openers (the author and his team have measured ultrasonic signals from such devices) to ultrasonic weapons, as marketed to joggers against dogs. Practical utilization of ultrasonic devices in rodent control part I, Electromagnetics vs Ultrasonics: a clarification, Noise nuisance caused by domestic garden ultrasonic pest control devices, Acoustical characterization and efficacy evaluation of ultrasonic pest control devices marketed for control of German cockoraches (Orthoptera: Blattellidae), Ultraschall: der horror aus nachbars garten [transl. then a combination of anxiety, stress and our knowledge of the human response to audio frequency noise can offer a plausible explanation for the symptoms (which nevertheless needs testing). There is a wealth of material on mechanisms for acuity [176][182] although a great deal is based on bone conduction rather than the airborne pathway. A statement by the manufacturer on the on safety of the Phasor Pain Field Generator states: We have selected a sound pressure level and a strength that we feel is safe to use and liability-free. Although some have confused the ability of LRAD devices to project beams of intense sound with the ability of parametric sonar to generate such beams, the LRAD does not use the technology of the preceding subsection. This author's interpretation of it would be If a group of only 18 men with an average age of 30, who work in the ultrasonic cleaning baths industry but for whom there is no quantification of exposure either to audio frequency or ultrasonic signals, is compared to a group of 20 men of similar average age who do not work in the ultrasonic cleaning bath industry, do the average (across the whole group) Hearing Threshold Levels from 250 to 8000Hz differ between the two groups? The average of the ultrasonic workers was worse by 27dB over the entire frequency range. Biological effect of ultrasound (translated from Russian). These tones report to an end of line device on each loudspeaker circuit which acknowledges receipt of the signal, which is then returned to the amplifier and repeated continuously across the hundreds of circuits throughout the stadium/building/space. 2013. Some types of pests are so good at hiding; it will take a lot of effort for you to figure out where theyre located. figure 6g with k and compare h with l). 2014. Assignment no. The review by Trenter & Walmsley [122] is recommended. As a form of discrimination, ultrasound in air has the peculiar characteristic that susceptible individuals may not even know that the adverse effects are caused by ultrasound as opposed to some other source (e.g. This identified the number of ultrasound-exposed subjects in table 4 of Macc et al. In principle free field microphones should always be pointed at the source of interest. This would negate comparisons. In. Cortical representation of tympanic membrane movements due to pressure variation: an fMRI Study. The current lack of evidence makes it unlikely that clinicians will consider VHF/US exposure to be a possible cause when confronted with patients experiencing these symptoms. Figure 1a shows the type of spectrogram (also known as a time-frequency plot) that can be taken with a smart phone equipped with an appropriate app. From the point of view of heating and cavitation, this is a sensible proposal, but in the absence of a mechanism for subjective effects, it needs careful testing against evidence, which includes an assessment of whether the current evidence base is sufficiently large. Given that workers in public places (as in figures 1 and and2)2) might feel adverse effects without identifying the source, the examination of the effects of long-duration exposure should be addressed [5]. Category 2 is labelled Unintended ultrasonic exposure. Although experiments with ultrasound in air generated death in insects and mice in 10180s as a result of 20kHz in air at 169dB re 20Pa [101], and dizziness and mild-to-very-unpleasant heating at crevices (fingers, skin clefts, nasal passages) in excess of 140dB re 20Pa in humans [3],[22],[101], these levels are almost certainly very significantly greater than those to which the public are being exposed. Do Ultrasonic Pest Repellers Really Work? These will need to be reconsidered if the research base is appropriately expanded, particularly with respect to the generation of subjective adverse reactions, which appear not to have been taken into account for any third-octave band higher than the one centred on 20kHz. One school and one major sports stadium were also tested, and both contained signals close to 20kHz. Different models have different components and manufacture materials that will ultimately affect the quality of your pest repellent. Dezember 1982 (BGBl. 20dB) in going from 1 to 10kHz [183]. For higher frequencies there are virtually no performance specifications. There is no evidence that air-borne ultrasonics can produce any specific direct effect on the brain or other parts of the nervous system [92]. Moreover, 5% of the 519 year age group is reported to have a 20kHz threshold that is 60dB more sensitive than the median for the 3039 year age group [10]. As a further point regarding equipment, Frank [196] took his measurements with a specific type of earphone (a Sennheiser HD250), and because of the significant high frequency differences (in terms of output, distortion etc.) Figure 3 makes clear the 65dB spread at 20kHz that relates to a factor of 3000000 range in intensity (and over 1000 in pressure; see the note ondB references in 2a(i)), for occupational MPLs. Since then, the old four-class system (Classes 03) has been replaced by a two-class system (Classes 1 and 2), and this older standard [88] is now considered obsolete and replaced by the newer one in Europe and the USA [86], which allows the dB tolerance at 20kHz. Interrupt your recording by placing your finger over the microphone, after the manner shown in figure 1a, to ensure the signal is not electrical pickup (check on the web which microphone you need to covermany phones have two different microphones, one for voice and one for functions like video recording, and that is the one you need to cover). As we already discussed, humans and animals generally cannot hear the ultrasonic pest repellents because of its frequency range. Although a current survey of modern devices is needed to update and/or correct this list, and quantify the likely exposures, a 1981 FDA report [5] catalogued ultrasonic sources including TV remote controls, humidifiers/vapourizers and devices to assist the visually impaired. Effect of ultrasonic vibrations on personnel working with ultrasonic equipment, A criterion for the prediction of auditory and subjective effects due to air-borne noise from ultrasonic sources, Exposure criteria for industrial ultrasound. the effect on very young children and animals brought close the device by parents or grandparents who are not aware of the signal; the effect on children with pre-existing conditions that make them especially sensitive (autistic spectrum disorder, hyperacusis, Williams syndrome etc. within the third-octave band centred at 20kHzfigure 3), with SPLs up to 109dB re 20Pa at a range of 1m from the source, increasing as one approached the source. American Conference of Governmental Industrial Hygienists (ACGIH). in schools), taking into account the false positives, with appropriate care for sufferers regardless of whether ultrasound is the actual source of discomfort; If genuine adverse reactions are found in workplace, residential or public settings, an assessment of whether normal measures offer sufficient protection (e.g. These data are based on the compilations listed by Lawton [45],[46], with additions. Ultrasonic sounds can't travel around furniture or structures or through drapes, establishing safe zones where pests can congregate. It argues that the guidelines for protecting humans from airborne ultrasound vary and are uniformly inadequate: for energy above 22.4kHz, they are based on avoiding ultrasonically induced hearing damage at the lower frequencies used to understand speech, taking no account of reports of the ability of airborne ultrasound in occupational settings to cause nausea, dizziness, tinnitus, fatigue, migraine and headaches. Occupational Health and Safety Administration (OSHA) 2004. 2007. Commercial ultrasonic units fall below this threshold; most units do not operate continuously, and sound pressures (except very close to the transducers) are less than 120dB. the need to assess the anecdotal stories from those who purport to have suffered in this way; and. Only the 1984 INIRC-IRPA [20] guidelines (built on a 1981 report [54]) considered public exposure, giving a very reasoned account of the differences that must be taken into account for public, as opposed to occupational, exposure (2b(iii)) but noting that these were interim because of the lack of definitive data. Light and easy to move, they can be plugged in the electric outlet in virtually every room, emitting high-frequency waves that prevent the rodents and bugs from entering, nesting, or settling in the respective venue. Standard hearing tests do not consider acuity above 8kHz, and although loss in this frequency range due to exposure at other frequencies has been established, the number of studies and cohort sizes remain small. Handheld prototypes have been reported generating pulses of sound of 1s duration at 125150dB re 20Pa, with the capacity to knock people off their feet [159], but any proven effectiveness might well rely on auditory effects rather than radiation forces, which would be too weak (4b). Estimations of the true values were inferred for this appendix by assuming that the number of subjects (n) takes a positive integer value, then multiplying the percentages given in the relevant table by n/100 to give a value m, the number of people exhibiting each of the symptoms if this value of n were correct. This is because unlike the devices measured in figures 1 and and2,2, ultrasonic devices tested in the past (such as ultrasonic cleaning baths) also generated audio frequency sound. There are studies that claim that pets are usually unaffected by ultrasonic pest repellers. by Nick Gromicko, CMI and Kate Tarasenko. 2008. However, there has not been proof of the effects of these ultrasounds on humans. AIB-Vinotte. Failure to recognize these flaws (in the scientific basis for applying past research to current exposures) has led to some dismissal among the scientific and medical communities of the claims by the public of adverse effects by VHF sound and ultrasound in air. As Davis et al. Thus an SPL of 100dB is recommended. Many InterNACHI inspectors are also qualified to perform wood-destroying organism (WDO) inspections, which can further identify and possibly diagnose insect infestation problems to help homeowners devise workable solutions. Technical report, Commonwealth of Australia, July 2002. Any potential for the primary ultrasonic frequency (e.g. All ultrasound emissions were accompanied by subharmonics produced in the audible high-frequency range as by-products of industrial ultrasonic processes. 2005. Barring subharmonics or the ability of the victim to hear above the upper limit expected by the manufacturer (figure 4), the ultrasonic weapon would not be expected to give to humans the audible cues and discomfort of an LRAD, although if the intended target is some non-human pest, it may claim to operate in such a way. At the lowest frequency plotted (200Hz), the scattered component of the sound field from a source placed behind the ear (figure 6a) is nearly uniform over the pinna and differs (notably in sign, which will of course be reversed half a cycle later) from the scattered field that would occur across the pinna if the same source is directly in front of the ear (figure 6e). official website and that any information you provide is encrypted This device is advertised for for potential crowd control applicationsExcellent for keeping out two and four legged pests from gardens, unauthorized areasAlso excellent deterrent to intruders when used in the home [156]. We have refused to accredit Mosquito primarily due to lack of evidence that it is safe. Whether they respond significantly or not at all is a function of the unknown variation in response in the population, and the as-yet unknown exposures. 2013. 2003. This occurs when some process or device (e.g. Audio beacon technology. Mathematical, Physical, and Engineering Sciences, Comment on Are some people suffering as a result of increasing mass exposure of the public to ultrasound in air?, http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA048115, http://resource.isvr.soton.ac.uk/staff/pubs/PubPDFs/Pub8039.pdf, http://www.av.se/dokument/afs/afs2005_16.pdf, http://www.ears-project.eu/emrp/ears-downloads.html, http://www.inrs.fr/media.html?refINRS=ND%202250, http://iiav.org/archives_icsv_last/2015_icsv22/content/papers/papers/full_paper_1304_20150330094349943.pdf, http://www.nohsc.gov.au/PDF/Standards/ASR/Noise2002ASR.pdf, https://www.researchgate.net/publication/23371373_Pest_control_with_sound_waves_ultrasonics_as_a_possibility_in_the_future_of_rodent_and_insect_control, https://www.osha.gov/dts/osta/otm/new_noise/index.html#appendixc, https://www.osha.gov/dts/osta/otm/new_noise/appendixc.pdf, http://www.gesetze-im-internet.de/arbschg/, http://www.gesetze-im-internet.de/arbschg/_4.html, http://www.gesetze-im-internet.de/bundesrecht/l_rmvibrationsarbschv/gesamt.pdf, http://www.iso.org/iso/catalogue_detail.htm?csnumber=26314, http://www.iso.org/iso/catalogue_detail.htm?csnumber=45103, http://pigeonpatrol.ca/wp-content/uploads/2014/11/tubesonic_pdf.pdf, http://pigeonpatrol.ca/wp-content/uploads/2013/12/ultrasonic_balcony_impact_pdf.pdf, http://www.bird-x.com/ultrasound-safety-pages-249.php, http://www.rdhmag.com/articles/print/volume-35/issue-02/columns/anecdotal-hygienist/don-t-lend-me-this-ear.html, http://hearinglosshelp.com/blog/ultrasonic-tooth-cleaning-and-tinnitus/, http://techcrunch.com/2015/11/07/wireless-power-charger/#.v1vbjhj:Ckow, http://www.bird-x.com/filebin/pdf/research/Ultrasound_Whitford-Study_observations.pdf, http://www.ftc.gov/opa/2001/05/fyi0128.htm2001/05/fyi0128.htm, http://info.kopp-verlag.de/hintergruende/deutschland/gerhard-wisnewski/ultraschall-der-horror-aus-nachbars-garten-.html, http://igo.nl/nieuws/algemeen/artikel/14842/Waarschuwing-voor-kattenverjagers-marteling-voor-mens-en-di, http://www.pigeoncontrolresourcecentre.org/html/reviews/ultrasonic-pigeon-and-bird-control.html, http://schlossmatte.ch/siedlung/tiervertreibergeraete.htm, http://www.health.belgium.be/eportal/Environment/19104803_EN?backNode=83&fodnlang=en#.VjXwWrfhDIV, http://www.amazing1.com/products/phasor-pain-field-generator-with-remote-control-140db.html, http://www.amazing1.com/content/download/PCC30_Instructions.pdf, http://www.nap.edu/openbook.php?record_id=10538, http://www.amazing1.com/products/phasor-pain-field-pistol-135db.html, http://www.amazing1.com/content/download/PSP60INS.pdf, http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/02/16/noise16.xml, http://www.mirror.co.uk/news/uk-news/exclusive-fury-as-tops-cops-refuse-294088, http://www.bbc.co.uk/schools/gcsebitesize/science/add_gateway_pre_2011/radiation/ultrasoundrev2.shtml, https://www.researchgate.net/journal/0001-5660_Acta_et_gemellologiae, http://www.fda.gov/Radiation-EmittingProducts/ElectronicProductRadiationControlProgram/LawsandRegulations/ucm118156.htm, http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?FR=1003.2CFRSearch.cfm?FR=1003.2, https://cdt.org/files/2015/10/10.16.15-CDT-Cross-Device-Comments.pdf. 1998. Macc I, Scapellato ML, Carrieri M, Maso S, Trevisan A, Bartolucci GB. HHS Vulnerability Disclosure, Help Moreover, because the human ear cannot detect the repellents waves, it is only the most sensitive people who may sometimes have issues after prolonged exposure. The application of simple physics to a single ear, therefore, reveals a far more complex pattern of results where, counterintuitively, humans who can detect frequencies as high as 20kHz may find it more difficult to determine the direction to the source than they would at somewhat lower frequencies even though basic physics tells us that directionality will improve with decreasing wavelength in this range. Buying an ultrasonic rat repeller is much safer than not having one. The increased susceptibility of some minorities has been exploited to produce deterrents aimed at them on the basis of this susceptibility, rather than on the basis of their actions. The greater directionality that is observed as the ratio of the sensor size to wavelength increases has been usefully exploited for decades, e.g. US Department of Defence. Pearson JD, Morrell CH, Gordon-Salant S, Brant LJ, Metter EJ, Klein LL, Fozard JL. In the best cases, ultrasonic pest repellers are very helpful to humans. Telegraaf 5 Aug 2015, Ueda M, Ota A, Takahashi H. The purpose of these devices is to target specific demographic groups, for example, by using high frequencies below 20kHz to prevent teenagers loitering around shops. The international standard [63] for the EHF range covers only from 8 to 16kHz, and furthermore, only includes data from subjects aged 18 and over. 2002. Plots of the occurrence of a range of subjective symptoms from the 2015 data of Macc et al. They are safe to use around kids and most pets because they cant get their hands into harmful chemicals. Reported cases of headache and nausea associated with airborne ultrasonic exposures appear to have been caused by high levels of audible noise from source subharmonics. Inspectors should always wear the appropriate personal protective equipment when inspecting areas of a home that could be a refuge for pests. Even for occupational exposure the evidence base is too small (if it were adequate, we would not see a factor of over 3 million in intensity between the lowest and highest occupational guidelines at 20kHz). Extended high-frequency (920kHz) audiometry reference thresholds in 645 healthy subjects, Characterisation of measures of reference acoustic cavitation (COMORAC): an experimental feasibility trial. Stelmachowicz PG, Beauchaine KA, Kalberer A, Jesteadt W. In (b,d) the vertical dashed lines on the box show the upper and lower frequency limits of the third-octave band centred on 20kHz, and the horizontal dotted line shows the level of broadband signal that would give the same third-octave SPL as the measured ultrasonic signal. The chances are these arent side effects caused by ultrasonic devices, and you have to check whether there is another underlying health issue. In part, this is because the manufacture of ultrasonic sources involves hazardous materials. There are now claims for the existence of a market for products that embed software on mobile devices (e.g. According to a study made by the National Institutes of Health (NIH), Cumulative effects to humans of using these kinds of repellers may include: Children, teenagers, and young adults are more likely to hear and pick up the ultrasonic sounds emitted by the repellers compared to older people. 2010. 2015. Humans are very sensitive to sound exposure; will the frequency of the repellent affect their physical or emotional state? The temptation has been to extrapolate to the whole current population the almost certainty that the original widespread claims of ultrasonic sickness were false (3b(i)), and reports suggesting mis-attribution in some members of the public for infrasonic exposure [81]. The effects disappeared when the tanks were in an enclosure. Although an LRAD source was aimed at protestors in New York at the 2004 Republican National Convention, the uncertainty regarding the effect on people at very short ranges meant it was not activated [165]. Some signs to watch out for include droppings, small tracks, gnaw marks, among others. Thats why its always wise to invest in a device that will actually keep pests away. Only sometimes! On reviewing this, Lenhardt [68] recommends his earplug design [69] and notes that goggles may be required if unproven theories that the eye is a route by which ultrasound activates the auditory system are proved [70]. The standard method for estimating noise induced hearing loss [79] does take into account the duration of exposure, but it is only relevant to noise at frequencies less than 10kHz. These conclusions were drawn by looking at averages of the cohort [114], whereas in a companion paper [115] Grezsik & Pluta returned to the factory they examined in 1983 [111] and tested again the 26 workers out of the original 55 who were still employed by the factory, using the same methods they employed in 1983. Although microphones with ultrasonic sensitivity are now commercially available, the smaller wavelengths associated with these higher frequencies are much more strongly scattered than the 2508000Hz signals typically used in hearing tests. Some of the signs of discomfort they observed with their pets include: Prolonged exposure to ultrasonic waves might be harmful to most people. However, it is important to appreciate that this legacy of knowledge was almost wholly taken with low amplitude tests. Health Canada [22] stated that most plausible mechanisms for non-auditory effects of airborne ultrasound on a human are heating and cavitation, though neither is relevant to humans below the levels associated with extremely intense ultrasonic fields, and certainly not for the potential human exposures of figure 1. Careers, Institute of Sound and Vibration Research, Faculty of Engineering and the Environment, University of Southampton, Highfield, Southampton SO17 1BJ, UK. [34]). It is also possible that some modern devices are inadvertently producing ultrasound (e.g. ","acceptedAnswer":{"@type":"Answer","text":"These devices emit high-frequency sounds, which can be perceived by pests, to make them feel uncomfortable, thereby driving them away from homes. For homeowners with multiple issues with rodents, cockroaches, and other pests, these devices have been proven to be effective in repelling these pests.\n\nIt has been proven by a group of scientists that research conducted proved that these devices on human ears after a prolonged exposure produced negligible adverse effects.\n\nIn other words, there was no reaction in humans.\n\nBesides, since the human ear cannot perceive this sound, the presence of these devices is insignificant. An ultrasonic pest repeller is an electronic device that controls pests by emitting a high pitched sound that may irritate, annihilate, or repel household pests. 2003. Bethesda, MD 20894, Web Policies Cockroach infestation, which is arguably the most pervasive and hard-to-eliminate type of pest infestation, especially in urban areas and industrial and commercial kitchens, is evidenced by the pest's droppings, which are pepper-like specs, typically found in kitchen cupboards, as well as their egg sacs, which are often spotted in hard-to-reach locations, such as cracks and crevices in kitchen cabinets and drains, and behind dishwashers and refrigerators. The range of available guidelines [3],[7],[12][28],[33],[34] is plotted in figure 3. Accession no: AD0024685. from German, Ultrasound: the horror from the neighbour's garden? Unless otherwise stated, the guidelines refer to the one-third octave level. Variables affecting ultrasound repellency in Philippine rats, Smith CP. In the presence of intense ultrasound, the tympanic membrane still undergoes displacement (extrapolating from figure 8). 19.2kHz) and (b) a calibrated microphone in a railway station. Theyre effective on almost any type of pest you can think of. In general, even when using calibrated microphones, because of both the equipment and the processing issues it is probably prudent to include approximately 3dB of expanded uncertainty when assessing calculations made from field microphone measurements [37],[38], and any guidelines (current or historical) following from them. For these, hearing protection might be worn (if shown to be adequate for VHF/US signals), but if the assessment of need comes from guidelines that follow from the current evidence base with its data predominantly taken from the averages of adult males, then it is not aligned with German occupational law (translated) that states Risks are to be controlled at source;individual protection measures are subordinate to other measuresspecial dangers for vulnerable groups of workers are to be taken into account (translated from Bundesministerium der Justiz und fr Verbraucherschutz, 1982) [51]. Figure 3 also makes clear the step change in allowed levels that occurs across the 20kHz band. Smaller pets, including guinea pigs, hamsters, and pigs can perceive these sounds and this can make them distressed. Pawlaczyk-uszczyska M, Dudarewicz A, liwiska-Kowalska M. Safety concerns have arisen, too; some users have reported that the sound can weaken the clarity of telephone conversations, interfere with burglar alarm systems, and cause muting in hearing aids. The Ben Piper and Richard Barham of NPL assisted with calibration, as did ISVR Consultancy Services (ICS), who loaned us equipment. Ultrasonic pest control is affordable, small, easy to use, lasts for years, can cover a large area, doesnt take too much space, and efficiently removes pests from your home. By contrast, people receiving VHF/US exposures in public areas, for exposures resembling figures 1 and and22 (that are not accompanied by a familiar audio frequency alert that most people can hear, such as the hiss of an ultrasonic cleaning bath), are currently ignorant of their exposures; they cannot reasonably be expected to wear hearing protection; they receive no monitoring of their exposure; they might also be exposed at home (by pest scarers) or during the commute (by public transport PAVA), and at work. Part IIexposure of volunteers. 2005. Habituation is a situation when a person or an animal gets used to a sound or a repeated stimulus. Let us assume as a working hypothesis that there exists, in the classified literature, a similar dearth of evidence to that found in the open literature (and which has led to the uncertainties outlined in this article as to effects and mechanisms; sections 2b(i,iv), 3b and 4). Filters for the measurement of audible sound in the presence of ultrasound BS EN 610121998, following IEC 61012-1990, British Standards 1998. The listing of these figures in this table should not be misinterpreted as an endorsement of them as guidelines by the author. Small wavelengths are not of themselves a problem: indeed we exploit the ability they give us to focus waves and form shadows in optics, because we are familiar with these processes, and never expect the short wavelengths of visible light to bend around corners as the long wavelengths of radio waves do.

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