Voltage Transients and Health Mikko Ahonen PhD, Researcher University of Tampere, Finland.

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Voltage Transients and Health Mikko Ahonen PhD, Researcher University of Tampere, Finland

Transcript of Voltage Transients and Health Mikko Ahonen PhD, Researcher University of Tampere, Finland.

Voltage Transients and

Health

Mikko Ahonen

PhD, Researcher

University of Tampere, Finland

Table of Contents

What are voltage transients – discussion about power quality

How to measure and record voltage transients

What are symptoms and mechanisms of effect

Impact on wellbeing technology and its development

A little Finnish-Russian pilot

My background

• Earlier worked in the Telecom and IT industry (TeliaSonera etc.)

• PhD in computer science

• Researcher at the University of Tampere

• Co-operating with FinnMedi Ltd (Tampere, Finland) & with Kazan State University (Russia) &with measurement manufacturers (Germany & USA)

• Founder and Partner Sustainable Mobile Ltd Measuring Services (http://www.sustainablemobile.com, http://twitter.com/SustainableM )

From sine wave to transients

- definitions

50 Hz sine wave & magnetic field

Generally, electricity in its purest form does not seem to cause health problems (Mandeville et al., 1997 &McCann et al., 1993)

Only magnetic fields starting from 0.3 uT (mikroTesla) have been linked to childhood leukemia (Greenland et al. 2000; Ahlbom et al., 2000). BUT results are inconclusive.

Are there other factors? High electric fields(in connection to low-level magnetic fields)

• Miller et al. (1996): 4 x leukemia risk in Canadian power company workers.

• Guénel et al. (1996): 7 x brain cancer risk, when electric utility workers were exposed more than 25 years

• Villeneuve et al. (2000) : 10 x leukemia risk , elevated Non-Hodgin’s lymphoma 1 2 3

Please, note: Very limited amount of evidence

"This study suggests that electric fields are potentially critical to cancer risk” 1

Voltage transients (or simply “transients” or “micro surges”)

“Transients are voltages and currents of short duration, typically less than one-half a cycle and possibly of larger amplitude than that of the normal steady state. These will either add or subtract from the nominal waveform.”

Source: Dranetz BMI (1997)

Harmonic overwaves (harmonics)

“We define harmonics as voltages or currents at frequencies that are a multiple of the fundamental frequency. For European systems, the harmonic order is 100 Hz, 150 Hz, 200 Hz etc.”

Source: Dranetz BMI (1997)

Intermediate Frequencies (IF): 300 Hz – 100 kHz

• Another name for the range of voltage transients• “As an overarching need, further research on

intermediate frequencies (IF), usually taken as frequencies between 300 Hz and 100 kHz, is required, given the present lack of data in this area.” (WHO, 2007)

From a review article – Voltage transients:

“Environmental exposure to High-Frequency Voltage Transients is an interesting EMF exposure metric, which might explain the spurious results from epidemiological studies using 'standard' ELF and RF exposure metrics.

However, at present, methodological problems in published studies prohibit the valid assessment of its biological activity.”

Source: De Vocht (2010)

What causes voltage transients?

Main sources of voltage transients

- Switching power on/off continuously- Static power converters with GR-diodes- Faulty electrical installations- Loose connections- Overloaded phases- Dimmers- Energy-saving lamps- etc

Picture: PhD, engineer Berthold Fuld (http://www.fuld.de/html/vortrag_pfc.pdf )

Laptops – occasionally extremely high voltage transients

Typical frequency values for highest micro surges caused by laptops:

D laptop computer = 25 kHz

D tower computer = 16.6 kHz

A computers = 12.5 kHz

Reason for high transient reading? Poor quality switching power supplies

Source: D. Stetzer

Low-frequency transient electric and magnetic fields coupling to child body / in the frequency range from 50 Hz up to 100 kHz - Ozen (2008)

“The results show that the transient electric and magnetic fields would induce higher current density in the child body than power frequency fields with similar field strength”.

118004-times higher!

Which frequency ranges match with highest amplitude of electrical fields?

Source: Lundmark et al. 2005

A related finding, shown on the video. Demonstrated with a frequency generator.

Which devices cause the biggest amplitude changes?

Source: Lundmark et al. 2005See also: Oliveira et al. (2006)

(VDU = Video Display Unit, HF-fitting=fluorescent tubes equipped with high-frequency electronic ballasts)

General observations

• Power quality has an effect on machines and their proper functioning.

• Ground current problem noticed first in farms in USA and Canada. Related to voltage transients.

• Various filters have been developed that reduce transients and harmonic overwaves.

• The term ”Reactive Power Compensation” means improving power quality.

How to measure voltage transients? (1/2)

Advanced

Graham-Stetzer Fluke Gigahertz Solutions Fluke ScopemeterMicroSurge Meter VR1170 NFA-1000 199C

Unit: dV/dt the average magnitude of the rate of change of voltage as a function of time. Measured often between 2 kHz – 150 kHz.

Graham-Stetzer Fluke Gigahertz Solutions Fluke ScopemeterMicroSurge Meter VR1170 NFA-1000 199C

How to measure transients? (2/2)

+

Oscilloscope

or

Spectrum analyser

Adapter for Harmonic Analysers /AuskoppeladapterFor measurement of conducted electromagneticinterference in the frequency range from 10kHz to30MHz based on CISPR 16 for measurements inaccordance to EN 55011…22

Output:L / PE / N

Transients in red – Minimal

Measured with a Fluke Scopemeter

Transients in red - Increased

Measured with a Fluke Scopemeter

Back to research results of transients

Armstrong, Thériault et al. (1994): Workers exposed to transients had 6 x risk of developing lung cancer (even non-smokers).

Consequence: The Canadian power company confiscated data and further research was not possible1

Milham & Morgan (2008) The teachers' chances of developing melanoma, thyroid cancer, and uterine cancer were particularly high, as great as 13 times the average.

Consequence: Researchers were not able to access the school any more 1 , 2 , 3 Please, note: Very limited amount of evidence + Extremely difficult to conduct studies in this area!

Regularly clusters where low level magnetic field or power density readings can not explain the whole “picture” - examples

http://www.news.com.au/national/another-abc-staffer-has-breast-cancer/story-e6frfkvr-1225833135423

Please, note: Other environmental factors like heavy chemical exposure should be understood.

http://www.nbcsandiego.com/news/health/Cancer-Cluster-at-UCSD-Building.html

http://blink.ucsd.edu/safety/resources/public-health/lit-building/

ELF-EMF may act at the cellular level to enhance breast cancer proliferation by blocking melatonin’s natural oncostatic action in MCF-7 cells (Liburdy, 1993; Luben et al., 1996; Morris et al., 1998; Blackman et al., 2001; Ishido et al., 2001, Girgert et al., 2010) . Is low level magnetic field value here more important than transient intensity?

Lots of discussion about melatonin and electro-magnetic fields:

Symptoms and improvements with transient filters (examples)

1. Allergy and asthma:- No inhalators needed any more- Less skin problemsHavas & Olstad (2008)

NFAM (2008)

2. Diabetes

- Type 1 diabetics require less insulin and Type 2 diabetics have lower levels of plasma glucose Havas (2008), video

3. Multiple Sclerosis and other neurodegenerative illnesses:- Less tremors - Better movability

Havas (2006)

3. Concentration and sleep:

- Less anxiety and restlessness- Better sleep quality

Genuis (2007)

Please, note: The evidence is still limited.

About mechanisms of effect

High tissue gradients by high voltage transients

• Bawin and Adey (1976) showed that a 56 V/m ELF field (in 50 Hz) induces a tissue gradient of 10-7 V/cm, whereas a 56 V/m 147 MHz signal induces a tissue gradient of 10-1 V/cm, a million times higher. (See also: Cherry, 2002; Blank & Goodman, 2004)

ProfessorMartin Blank

About mechanism: Stress response in DNA• ”Induction of the stress response involves activation of

DNA, and despite the large difference in energy between ELF and RF, the same cellular pathways respond in both frequency ranges. Specific DNA sequences on the promoter of the HSP70 stress gene are responsive to EMF, and studies with model biochemical systems suggest that EMF could interact directly with electrons in DNA. While low energy EMF interacts with DNA to induce the stress response, increasing EMF energy in the RF range can lead to breaks in DNA strands”. Blank & Goodman (2009)

About mechanism: Alternative explanations

• Atmosferics, weather-related electrical activity in kHz-range have historically caused health problems (Schienle, Stark, Walter & Vaitl, 1996; Reiter, 1995; Dubrov, 1978) and now this frequency range is artificially created in the electrical network.

• Certain frequencies inhibit DNA-repair and cause weakening of the immune system (Belyaev et al. (2009), RNCNIRP (2008). Frequency-windows exist and some frequence/power density combinations are harmful. (Blackman, 2009).

About mechanism – One expert opinionTransients are created when current is repeatedly interrupted. A CFL, for instance, saves energy by turning itself on and off repeatedly, as many as 100,000 times per second.

So how does the human body respond to this pulsing radiation? "Think of a magnet," explains Dave Stetzer, an electrical engineer and power supply expert in Blair, WI. "Opposite charges attract, and like charges repel. When a transient is going positive, the negatively charged electrons in your body move toward that positive charge. When the transient flips to negative, the body's electrons are pushed back. Remember, these positive-negative shifts are occurring many thousands of times per second, so the electrons in your body are oscillating to that tune. Your body becomes charged up because you're basically coupled to the transient's electric field."

Keep in mind that all the cells in your body, whether islets in the pancreas awaiting a signal to manufacture insulin or white blood cells speeding to the site of an injury, use electricity — or "electron change" — to communicate with each other. By overlapping the body's signaling mechanisms, could transients interfere with the secretion of insulin, drown out the call-and-response of the immune system, and cause other physical havoc? 1 , 2 , 3

About mechanism:

There is much we don’t know, no single mechanism is fully established!

Impact on wellbeing technology and its development

Mobile phone components – producing transients continuosly in stand-by mode

Question: How risky is it to keep to a mobile phone attached to the bodycontinuously? Is it really a personal health monitoring device?

Smart meters and other utility equipment – transmitting RF-signals in the electrical circuit and power lines• Vignati & Giuliani (1997) investigated

powerlines: “Electric current at 100 kHz can penetrate much more deeply through the plasmatic membrane than current at 50/60 Hz.”

• Italy: Frequencies used by utilities for data transmission range from 104 to 288 kHz.

• Israel: Powerlines lines are used to transfer information. The frequency range is 30 to 450 kHz.

• What is the current and future situation?• Which frequencies are the most critical

from health perspective?

What happens when RF-frequencies are “run” in a powerline that is originally optimised for 50 Hz sine wave?

The gain of the powerline as a radiator increases rapidly with frequency (Hare, 2003 ). Powerline starts to act as an antenna and extends wider.The gain of the powerline as a radiator increases rapidly with frequency (Hare, 2003 ). Powerline starts to act as an antenna and extends wider.

Filters reduce voltage transients

• A simple condenser/capacitor as a filter

• Or… a special line filter (from Graham-Stetzer, Bajog etc.).

Suitable for interference suppression for switching power supplies and phase controlled modulators

Observation: Voltage transients are similar to pulsed microwaves.Making epidemiological studies is very complicated.

Radio and TV-transmitters:Effect: Dolk et al. (1997a), Hocking & Gordon (2003),

Ha et al. (2007), Mascarinec et al. (1994, Michelozzi et al. (2002), Morton & Phillips (1983), Park et al. (2004) [Mostly increased leukemias and lymphomas]

No effect: Dolk et al. (1997b), Mersenich et al. (2008)

Mobile Phone Base Stations:Effect: Abdel-Rassoul et al. (2007), Eger et al. (2004), Hutter et al. (2006), Navarro et al. (2003), Santini et al. (2003), Wolf & Wolf (2004), Blettner et al. (2008)[great variety: from headaches to breast cancer]

No effect: Meyer et al. (2006), Berg-Beckhoff et al. (2009)

http://www.chronicexposure.org

Our little pilot in a Finnish (and a Russian) school

• Starting point: Teachers and students had many health problems and complaints in a high school. Minimal amount of mold was found and removed. Ventilation was improved in the school. Still, problems remained.

• We measured transients in every class room. Protocol: Similar to Trushina et al. (2010), co-operating with prof. Maksim Trushin

• Thereafter we checked if symptoms and transient readings match. Interestingly: There was a match, the 2 teachers who had the biggest health problems (asthma that required inhalators, skin problems, watery eyes, continuous coughing) worked in those 2 class rooms with highest transient readings.

• Outcome: Filters that drop the HF-transients were installed for testing purposes. Symptoms of teachers were reduced. We need(ed) more information about exposure conditions at home + earlier chemical exposure. Reseach continues both in Tampere-area and Kazan …

Additionally, we have a pilot starting in a hospital.

Are we saving energy on the cost of health?Already we know that many appliances and machines could be designed in a better way.

Our research hopefully helps to make those “Smart Meters”, “Smart Grids” and “Smart Houses” more sustainable and healthier. Additionally, electronics, wires and power supplies in schools, homes and work places could be improved with small costs and simple means. Within Green IT and Green Computing we should perhaps start discussing about health issues and transients.

What about standards and guidance levels?

ICNIRP-guidance level – no consideration of: - wavelength/frequency - overall duration of exposure (continuous, interrupted), acute and

chronic exposures - polarization (linear, circular) - continues wave (CW) and pulsed fields

(pulse repetition rate, pulse width or duty cycle, pulse shape, pulse to average power, etc.)

- modulation (amplitude, frequency, phase, complex) - static magnetic field at the place of exposure - electromagnetic stray field (Belyaev, 2008; Blackman, 2007)

SanPin is perhaps the only health standard that considers these?

DIN EN 61000-3-2; VDE 0838-2:2010-03 Electromagnetic compatibility (EMC)

Thank you!Questions and comments welcome!

Mikko AhonenPhD, ResearcherUniversity of TampereFinland

Telephone +358-3-3551 8069Skype ahosmikko

E-mail mikko . ahonen [at] uta . fi

Info http://www.uta.fi/~mikko.ahonen/

Blog http://beyondradiation.blogs.com