A special case of LFN (Low frequency Noise) called the Hum: gas, electric and magnetic modern day living bits all with scientific proof and none of which can be denied, by Dr Chris Barnes Bangor Scientific Consultants email email@example.com
Released for first Internet Publication 19th January 2013
Definitions, theories, acoustic and (electro) magnetic spectra of the Hum are briefly reviewed. Conduits for the Hum components into houses are discussed and independent evidence cited. Experimental evidence for magneto-vibration conversion in mammalian systems and magneto-orientation mediated calcium ion release in brain tissue at modest DC and AC field strengths is also cited as being of particular relevance to the behaviour of the Hum for some individuals. It is also concluded that there is strong support in the existing literature for the Hum to be a facet of electrical supply in particular power flow oscillations and dirty electricity as previously asserted by the author’s numerous papers but modifiable in form by infrasound from gas mains.
According to Leventhall (2004)  an LFN is a Hum if its source cannot be readily traced and the Hum is the name given to a low frequency noise which is causing persistent complaints, but often cannot be traced to a single, or any, source. If a source is located, the problem moves into the category of engineering noise control and is no longer "the Hum", although there may be a long period between first complaint and final solution. The Hum is widespread, affecting scattered individuals, but periodically a Hum focus arises where there are multiple complaints within a town or area. There has been the Bristol Hum (England), Largs Hum (Scotland), Copenhagen Hum (Denmark), Vancouver Hum (Canada), Taos Hum (New Mexico USA), Kokomo Hum (Indiana USA) etc. A feature of these Hums is that they have been publicized in local and national press, so gathering a momentum which otherwise might not have occurred, possibly increasing the number of adverse reactions. Although the named Hums, such as Kokomo, have gained much attention, they should not be allowed to detract from those cases in which individuals suffer either on their own or in much smaller groups such a family groups in isolated premises, for example. The sound of the Hum is subjective to individuals. Even in the areas of multiple complaints, the description is not entirely consistent, possibly this may be because people use different words to describe the same property of a noise. The general descriptors of the sound of the Hum include: a steady hum, a throb, a low speed diesel engine, rumble and quasi periodic pulsing. The effects of the Hum may include pressure or pain in the ear or head, body vibration or pain, loss of concentration, annoyance nausea and sleep disturbance. These general descriptions and effects occur almost internationally and with close similarity.
The present author has previously stated that he feels the Hum is one of the most perplexing scientific jigsaws yet sadly one of the least investigated [Barnes 2-4]. There are only a handful of University academics worldwide who have either been asked to investigate anecdotally the Hum or to perform any serious research on it. The majority of the advancement in this area has come from Independent Scientists such as the present author and from amateur Hum investigators such as Dawes in the UK and Kohlasse in the USA (personal communications).
It is the author’s experience that individuals researching the Hum often stick rigidly to their own agenda and particular sphere of blame. There are, for example, those such as Dawes who blame entirely the power grid and its electro-gravitation interaction with our earth and space environment . There are others such as Fox who have blamed entirely gas mains and motorways. There are others who have blamed radio communications technology and finally there is Deming who has suggested that the Hum best correlates in space and time with the operations of certain military aircraft such as TCAMO .
With a topic as emotive as the Hum it is always conceivable that large utility organisations are already perfectly aware of the damage they are doing to people and are purposely perpetuating misinformation. The internet as large a pool of misinformation and disinformation as it is of valid and accurate information. Whilst the present author has been employing internet authoring and being of scientific discipline and training and not affiliated to any of these organisations he has tried to present a very balanced viewpoint of the Hum and has only presented the facts as they relate to the scientific measurement and observations he has been making or where they relate to or are evidenced from allied or other scientific disciplines.
At the author’s home, the general observation is always that the Hum is present when there is infrasound in approximately the range 1-20 Hz, some narrow band pulsating acoustic frequencies usually related to mains frequency sub-harmonics, fundamental and inter-harmonics and an acoustically very quiet zone above about 300 Hz. This is more likely at night. Allied with this acoustic spectrum electromagnetic spectra, however recorded more or less, if not entirely, mirror the acoustic findings. The Hum appears more intense and occasionally very difficult to screen with earplugs when a magnetic comb spectrum is also present. The author who has personal experience of the Hum has also noticed that its intensity depends on which position he sleeps in. He has previously commented on a possible interaction between the earth’s DC magnetic field and the Hum (ref) and this directivity effect is a possible facet of that.
Thus it would appear the main questions which need to be asked are as follows. Firstly, what are the conduits for the above spectra and the Hum? Secondly, do these provide frequency or frequencies that would give rise to people’s experience of the Hum? Thirdly, is there any independent scientific research to validate the above, especially the magnetic hypothesis, which being new is most open to challenge?
Conduits for the Hum and its components
The author has discussed this topic at length elsewhere  but would like to point out some independent evidence which has come to light.
Regarding firstly infrasonic signals, gas mains can indeed be the source of these, see VV Krylov (1995 and 1997). According to Krylov, no surface vibrations are noted with gas mains due to mismatched Rayleigh wave velocities but they do conduct infrasound directly into houses.
On the other hand according to AV Mamishev (1996) , buried live three phase cables do give rise to surface acoustic vibrations. Here is a very significant extract from the Mamishev publication. ‘The implementation of a piezoelectric acoustic sensor for nonintrusive detection of the energization status of 3-φ electric power cables is presented. Simultaneous excitation of a piezoelectric crystal by acoustic vibrations and electric field may occur. The Fourier spectral analysis of the sensor's output signal is used to determine the current loading status of the cable. Test results are included for both shielded and nonshielded 3-φ cables. Also, the possible use of an optical fiber interferometer for acoustic wave detection is discussed.’
Whereas gas pipes can conduct sound directly into houses, a window is generally one of the weakest links for transmission of LFN from an external source Z.Yu et al 2010 http://www.ingentaconnect.com/content/ince/ncej/2010/00000058/00000002/art00008. Airborne sound from electrical grid sources outside could potentially thus propagate in this manner, double glazing especially forms a low pass filter. The Hum typically has low frequencies.
Within a house, room resonances and Helmholtz effects can amplify specific frequencies, see Vinokur (2004) . I too have published on this effect, see ‘Chimneys, toilets and turbines: do electrical power systems always have to be the cause of the Hum or can they just show us symptoms?’ By Dr Chris Barnes Bangor Scientific and Educational Consultants .
Gas, electric or both?
The author has recently shown that the Hum does not take place in certain countries which do not have modern power grid controls and do not have renewable energy. Gas is prevalent in these countries. One postulates therefore that infrasound from gas mains alone is not the cause of the Hum.
The author has first hand personal communication with a lady who hears the Hum extensively in Oxfordshire. This same lady visits Texas in the USA extensively. The area she visits has no gas mains and no pumped storage hydropower and no significant wind power. She never experiences the Hum in Texas. All other infrastructure is comparable between the two locations.
The author has previously shown that Hum like effects can be simulated under laboratory conditions by using frequencies in the region of 50 Hz and infrasonic sub harmonics. Is it possible then that gas mains could provide infrasound at appropriate frequencies to ‘match’ 50 Hz as above and provide the Hum? Subtle differences in this matching could account for the differences in Hums mentioned by Leventhall and previously thought by both he and the present author to be accountable purely in terms of subjectivity. Certainly the Hum which the author has experienced in a car parked immediately underneath power lines is not completely perceived as identical to that at his home location although many of the fundamental frequency elements are the same.
Whereas the jury remains out, it would seem the majority verdict may be power oscillations and dirty electricity is to blame for the Hum but that gas mains’ infrasound proven to enter houses (Krylov) may be an inevitable modifier.
Magnetic perception of Hum – madness or made of firm scientific foundation?
The author has previously advanced a magnetic hypothesis for both the generation and perception of Hum. This is in no way meant to detract from the notion that in some cases the Hum is predominantly an acoustic effect but merely to re-iterate that the two components magnetic and acoustic are inexorably inseparable. The author’s theory of detection may for some appear farfetched and over complicated. Just because something is complicated does not mean it cannot be correct provided we stick to Occam’s Razor or Einstein’s Principle. At least in a mammalian animal model, it has recently come to light that there is a body of scientific experimentation which supports the author’s hypothesis, especially Towe 1988 . It is highly relevant and wholly instructive to simply consider the wording of the abstract of Towes’ paper as follows: ‘A method for the non-invasive measurement of low-level ionically conducted electric currents flowing in electrolytes and tissue is investigated. Experiments show that the application of oscillating magnetic fields to current-carrying media will cause focal Lorentz forces which generate detectable vibrations. These vibrations can be sensitively and noninvasively detected by surface contact detectors and can be used to determine the magnitude of internal current flows. Microampere-level currents introduced in hamsters to simulate natural bioelectric currents have been sensitively detected by this approach.
Secondly, it is further instructive to consider the next abstract of Dr. C. F. Blackman1, (2005) ‘ The frequency dependence of the electric and magnetic (EM)-field-induced release of calcium ions from an in vitro brain tissue preparation has been shown to be a function of the density of the local DC magnetic field (BdC). In this study, we demonstrate that the relative orientation of the Bdc and the magnetic component (Bac) of a 315-Hz EM signal (15V rms/m and 61 nT rms) are crucial for the induced release to be observed. The induced release occurs only when the Bdc and the Bac are perpendicular, and not when they are parallel. This finding is consistent with a magnetic resonance-like transduction mechanism for the conversion of EM energy into a physicochemical change, and contrasts with the requirement for parallel Bdc and Bac components in the diatom-mobility experiments of Smith et al. A review of the exposure conditions in the rat behavioral experiments conducted by Thomas et al. identifies un-hydrated calcium and zinc ions as alternatives to lithium ions as candidates for interaction under parallel magnetic-field orientations but fails to reject perpendicular orientations as an alternative basis for the phenomenon. Investigators that attempt to confirm the rat behavioural experiments should be aware of the conflicting exposure conditions that can be assumed to be operative, and they should design their experiments to test all conditions accordingly .
In other words the crucial importance of alignment between a local DC magnetic field and an oscillating magnetic field in responses of brain tissue has been in vitro and in vivo. These are subtle and modest field levels of similar magnitudes to those associated with the Hum and may well help explain observer orientation and sleep position effects in relation to Hum perception.
If we consider the earth’s field as a fixed DC field and the AC mains as an oscillating magnetic field, this taken with the previous paper is sufficient both to explain how a deaf person might be able to perceive the Hum and it is further sufficient to explain how the Hum might appear to be magnetically enhanced at certain times. Further and importantly it may account for why the Hum maximises in buildings with steel girders and corrugated roofs or near buildings with such structures because of local DC magnetisation.
It is concluded that there is strong support in the existing literature for the Hum to be
1. A facet of electrical supply as previously asserted by the author’s numerous papers
2. Modifiable by infrasound from gas mains
3. Magnetically perceived in some individuals
12. Importance of alignment between local DC magnetic field and an oscillating magnetic field in responses of brain tissue in vitro and in vivo http://onlinelibrary.wiley.com/doi/10.1002/bem.2250110207/abstract