Category Archives: Sensitive Electronic Equipment EMI (Electromagnetic Interference) Grounding and “Dirty Electricity”

Equipment EMI (Electromagnetic Interference) Grounding and “Dirty Electricity”

EMF Testing Indoor Air Quality Radon Gas Testing: 214.912.4691 Dallas – Houston – Austin – Fort Worth

Powerline Home Safe Distance Cell Phone RF Surveys

Cell Tower Site on High Voltage Power Line near homes in residential area in North Dallas – EMF Testing and Surveys

EMF Testing / Magnetic Field Survey & Safe Distance Measurement Services

EMF testing for those concerned about living near powerlines and feeders is available for commercial clients and limited residential with reports that range from verbal to complete reports with photo documentation and graphics. We also provide consultation on viable strategies and products for EMF protection. We travel all over Texas and cities in adjacent states including Dallas, Houston, Fort Worth, Austin, San Antonio and Oklahoma City.

RF (Radio Frequency) Scans and Evaluations – Maximum Permissible Exposure (MPE)

We test RF energy for frequency and amplitude in order to find sources and evaluate safety with respect to FCC regulatory, compliance and precautionary guidelines, and to determine potential interference issues between wireless routers, cell phone repeaters / boosters, Radio Frequency Identification (RFID) systems, and wireless microphone / audio / video data systems.

Magnetic / Electric / RF & EMF Shielding Consultations including proper grounding

If you have an issue with electromagnetic energy that is either a safety issue or causes equipment interference, we are fully qualified to assess, troubleshoot and make sound recommendations to fix or mitigate the situation.

Radon Gas Measurements & Surveys (Short / Long Term Testing)

With a background in radon and radiation safety, we are capable of evaluating and reporting on radon gas levels, how they compare with EPA standards and whether a mitigation solution is called for.

EMF Testing for Electrical Wiring Issues Indicated by Excessive EMF Fields

Whether you believe in the safety hazards of EMF or not, the most common source of high EMF fields inside the home is improper wiring which fails to conform to current NEC code. ScanTech can detect and direct repairs on electrical wiring that manifests as an abnormal magnetic field.

Preliminary Construction Surveys / Property Transfer Phase I Environmental Site Due Diligence Survey testing regarding Indoor Air Quality (IAQ) – EMF Consultation for Safety and potential EMI – Radon Testing for Multi-Family Dwellings and Commercial Buildings.

We are often called out to site before a structure or complex is erected in order to survey and communicate any possible issues and the potential impact of nearby power lines, substations, transformers, cell towers and other EMF/RF generating sources. We also make construction recommendations for minimizing electromagnetic field emissions for safety and electromagnetic Interference concerns with sensitive manufacturing and research equipment.

Indoor air quality testing for VOC levels regarding Certificate of Occupancy permits according to City of Dallas Green Ordinances. Also known as the 804.2 Post-Construction, Pre-Occupancy Baseline IAQ Testing which is a 4 hour test for 500 uG / m^3 or less of VOCs.

Magnetized & Radiation Contaminated Metals, Stone and Imported Products

ScanTech has been in the radiation survey business for over 10 years and is routinely called upon to investigate cases of suspected radioactive contamination and magnetized ferrous metals which can cause unusual issues. Our instrumentation includes several Geiger counters with capable of detecting Alpha and Beta particle emissions, X-Rays and includes specialized Gamma radiation scintillation detectors.

Weak Cell Phone Signal Reception Issues & Wireless LAN Problems / RFID Interference

Weak Cellular Phone (including 2G / 3G / 4G LTE) & Wireless Strength Measurements with consulting for correction / mitigation in commercial buildings, residential and multifamily properties with poor coverage, slow data rates and dropped calls for all major telecom and communications carriers including Sprint, T-Mobile, Verizon, AT&T for smartphones, tablets, iPads, etc. Radio Frequency Identification system troubleshooting and interference issues investigated. We also perform FCC RF Compliance surveys for MPE (Maximum Permissible Exposure) including rooftop antenna installations.

Implanted Biomedical Device EMF / EMI Measurement Compliance Surveys and Testing for Patient Safety

Medical Device Compliance Testing (Pacemakers, Implantable Defibrillators, ICD’s etc. – Medtronics, St. Jude Medical, Boston Scientific, Mortara) for individuals returning to work or home after implant surgery to identify potential hazards from AC/DC Magnetic and Electric Fields, Microwaves, RF and general EMI (Electromagnetic Interference).

Hospital Infant Anti-Abduction Security Systems

ScanTech troubleshoots RFID integrated systems designed to protect neonatal care facilities that employ systems such as Hugs by Stanley Healthcare and MyChild by McRoberts Security Technologies.

Electrostatic Discharge (ESD) Testing, Consulting And Evaluation for Commercial, Industrial and Biomedical Companies / Applications / Clients

We have the equipment to determine the sheet resistance of ESD flooring material and if anti-static grounding is working as well as the ability to identify troublesome materials and processes which can cause equipment malfunction and electric shock / fire / explosion hazards. We can also measure relative air ion counts, humidity and the direct DC static voltage on surfaces (positive or negative) up to 30,000 V to determine which objects in the environment may be damaging your static sensitive equipment.

Indoor Air Quality (IAQ) Surveys to Determine Relative Air Cleanliness PM2.5 / PM10 / HEPA Filtration Efficiency / Formaldehyde / VOC / CO2 (Carbon Dioxide) / O2 Oxygen % Concentration & Contamination for Commercial Building and Industrial / Occupational Atmosphere Evaluations with expertise in Nanotoxicology and Medical Environmental Illness Testing

We have time based datalogging air laser analysis available to characterize particulate matter such as small particle contaminants (down to 0.5 microns such as bacteria) and large particle counts (2.5 um and larger) for potential pollen, dust and mold detection which are also known as RSPs. (Respirable Suspended Particles) We can also check for formaldehyde concentrations and VOCs (Volatile Organic Compounds) levels from outgassing materials such as pressed wood flooring or glues and other binders.

Elevated CO2 (carbon dioxide) levels are indicative of Sick Building Syndrome and poor air exchange characteristics in a structure.

New nanomaterials on the market have raised concerns about the potential toxic effects of nanoparticles (such as carbon nanotubes, titanium dioxide, silver NPs, etc.) in particulate, aerosol, aqueous forms and their in-vivo effects.

Commercial, industrial, occupational health and limited residential applications.

http://www.indoorairqualitytestingdallas.com/

OSHA Sound / Noise Level Surveys for Safety Audits

Sound (Commercial) & Industrial Safety field surveys and measurement including for acoustic OSHA sound and STC (Sound Transmission Class) noise levels / ordinances / testing (meeting ANSI & IEC Type 2 standards) to determine compliance and evaluate potential issues with excessive or disruptive noise.

Photometric Glare & Illumination (Lighting Level) Surveys for Safety, OSHA and City Ordinance Compliance

Photometric mapping to identify poor / insufficient / excessive illumination, security camera glare, ATM lighting security assessments, ADA lighting requirements / compliance, and privacy. Many cities have enacted ordinances which limit the amount of light emanating at the property line at night in foot candles. (fc) We can also measure lighting flicker rates which can cause headaches and other performance issues as well as evaluate possible disruption of circadian rhythms which lead to insomnia and lack of restful REM sleep.

Metallurgical Analysis & Consulting

Materials analysis for ferrous / non-ferrous metals / alloys. Tools and tool steel quality evaluations for carbon content. Also magnetic / RF / electric shielding capability, corrosion resistance, heat resistance, degree of temper, quench methods, elasticity, weathering, and electrical quality consulting. Metamaterial composite research for nanotechnology, biomedical, and exotic applications. (graphene, nanoparticles, carbon nanotubes, nanodiamond, etc.) Radioactivity testing for scrap metal or other suspected products.

Dirty Electricity – Is it really “Electropollution” or a Real Threat to Health and Safety? The Dirtier Truth

Comparison of a "Clean" Powerline Signal (top) with one that has EMI or High Frequency Noise (bottom)

Comparison of a “Clean” Powerline Signal (top) with one that has EMI or High Frequency Noise (bottom)

“Dirty electricity” is a rather unscientific term used loosely to describe a signal waveform that has extraneous noise components riding on top of it – typically of higher frequencies and/or a transient random nature.

It is more accurate to describe it as a noisy signal or more specifically as 120 Volt 60 Hz AC with high frequency components. Incidentally, ScanTech Consulting has the capability to evaluate the amount of high frequency noise on a power line in the ranges of 10 KHz – 10 MHz in order to diagnose possible EMI and equipment interference issues. (see picture below)

The controversy is whether or not this phenomena has any measurable impact on human health and safety. Please notice that the use of the terms “dirty” and “electropollution”  have a negative connotation and will tend to immediately bias any reader. Also, the term “dirty electricity” and “electropollution” are not the same. Dirty electricity is any electromagnetic waveform that has unwanted and / or noticeable harmonics and regular or intermittent transients in either the voltage and / or the current component. Electropollution is another relatively unscientific term used by certain EMF consultants / specialists to describe potentially any and all electromagnetic waves of artificial origin, so dirty electricity is only a small subset of EMFs that could be included in the meaning of electropollution.

Bear in mind that there are a number of natural sources of electromagnetic noise such as the Schumann resonances, (spectral peaks in the Earth’s natural ELF field) and radio atmospheric signals which are known as “whistlers” and “sferics” (or also spelled “spherics”) which are produced by global lightning strikes that interact with the ionosphere and Earth’s magnetosphere.

Now before you think that I am completely dismissing the topic out of hand, I can tell you as an electrical engineering graduate that extraneous noise usually is a real problem, but it is normally far more so to equipment (particularly sensitive electronics) directly powered by it rather than to human health. I do have equipment designed to track this down, but this applies more to the commercial arena where (for example) anomalous equipment operation can be caused by a nearby defective (or poorly filtered) LED bulb or an arcing motor in some other part of the building.

Most power supplies are designed to filter out and/or minimize the potential damage that these noise spikes and transients can do before they reach the vulnerable logic components of your computer or charging cell phone. In addition, surge suppressors and UPS (uninterruptible power supplies) are an inline solution to prevent some of the larger transients such as those from a nearby lightning strike from doing something unpleasant such as zapping the motherboard of your PC.

Actual Scientific Measurement of High Frequency Electrical Noise on an AC Powerline

Actual Scientific Measurement of High Frequency Electrical Noise on an AC Powerline

They are also designed to filter out noise that may corrupt data such as on an Internet LAN cable or in critical medical and scientific equipment such as an EKG monitor or scanning electron microscope. But on occasion due to ground loops or incompatible equipment grouping, even the best power supplies can be thwarted if the data/signal lines themselves have corrupted information and / or spurious noise. In this case, you are looking for what is known as S/N or the signal to noise ratio.

So what about the effects to human beings? Does the electric noise on your 60 Hz AC mains actually cause any health problems?

I find it unlikely for several reasons. For one, the overall amplitude of the noise is typically much lower than that of the 120 V AC already on the lines – usually by an one to two orders of magnitude. (at least 10 – 100 times less) Then assuming you are not directly connected to the line (which would be a far more dangerous and immediate problem than any alleged long term health effects) you have to consider the electric near field that is present near any energized line with voltage.

The electric field “couples” or induces voltages in the human body with very poor energy transfer because the very high dielectric constant of water present in the body shields the internal tissues, cells and organs. The resulting induced internal voltages and current in the body from external fields are reduced by an order of 1,000,000 times less.

So even with an external electric field of 1000 Volts / per meter (V/m) the induced voltages inside a human would be on the order of 0.010 V/m (10 milliVolts) or less. This is much less than the typical voltages generated within the heart and brain which are from 1 – 10 V/m. Furthermore, the endogenous DC fields generated by the flow of ionic current through cells in the body is on the order of 10 – 100 V/m.

I find it hard to believe that a 10 milliVolt field could substantially perturb a system that routinely generates voltages that are 100 – 10000 times greater. Again, this is within a 1 KILOVOLT / per meter electric field which is much higher than you will see anywhere except inside of an industrial electric room or underneath a high tension line.

The electric field generated by the alleged dirty electricity has a greatly diminished amplitude – probably no more than 10 V/m. Divide that by the same attenuating factor of 10^6 (1 million) and you wind up with induced voltages of 0.0001 V/m which is in the microvolt range.  (100 microVolts) This is even more unlikely to cause any noticeable change inside the human body given the fact that the resting membrane potentials of most human cells range range from -40 to -80 millivolts which is at least 400 X to 800 X greater than the 100 microVolts cited. The negative numbers for the internal voltages of cells are stated as such because you are measuring the voltage with respect to the ECF (Extracellular Fluid) surrounding cells which is used as a ground reference.

And again, this is in a 1 kiloVolt / meter field. What you encounter routinely inside of a home is at most 100 V / meter or so, and more typically 1-10  V /m. So divide that 100 microVolts by 10, 100, and 1000 and you wind up with 0.1 – 10 uV (microVolts) being induced in the body which is hardly a drop in the bucket as far as electrochemical signaling in the body is concerned. There is probably a greater pathological effect from listening to Barney The Dinosaur than this minuscule amount of “dirty energy” injected into a human host.

Even if there are minor effects, the body is an organism with a renowned impetus and ability to maintain equilibrium under a range of conditions. This is why we usually don’t perish as soon as something affects our blood pH, body temperature, glucose levels, etc. Our bodies are constantly keeping up with an influx of stress, bad food, bacteria, substandard air and food quality and a plethora of other threats and chemical / genotoxic insults. We only become ill when a substantial imbalance develops that our system cannot compensate adequately for.

In addition, many of us already have DSL for high speed Internet access which runs routinely pulses high frequency signals through telephone lines and yet I never hear any fuss or concern expressed over this medium. Granted, the practice of using twisted pair conductors does prevent this “noise” from radiating any appreciable distance, but it is in the high frequency ranges that many claim are damaging when present on a power line. I find it interesting that certain so called “experts” seem to cherry pick what type of noise is clean or dirty.

At any rate, I do not claim that electromagnetic energy is COMPLETELY harmless, only that it is better to calmly examine actual data and put said risks into proper perspective.

But whether you are interested in “cleaning up dirty electricity” for either the benefit of your electronic equipment or because you are concerned about the safety risks to your health – I would strongly advise that you read this article concerning devices that claim to eliminate electrical noise / health risks and what the real effects are:

EMF – Harmonics, and questionable means to “clean” them

This is your friendly Dallas / Fort Worth / Houston / Austin EMF Testing Inspector signing off for now.

Stay Well!

SCANTECH EMF CONSULTING  214.912.4691

LED Lighting vs. CFL and Incandescent Bulbs – A Considered Commentary Regarding EMF & EMI

Incandescent CFL LED Bulbs

ARE LED LAMPS BETTER?

In theory for many applications, yes, but in practice there are several problems with them. (here is a personal repost from a technical forum I belong to)

While the LED itself has a long MTBF (Mean Time Between Failure) the weak point in LED bulbs is the AC/DC converter circuitry. In the 7 LEDs I have bought so far in the past 4 years, I have had 3 failures. One of them actually failed in less than a month which is atrociously worse than virtually any incandescent I have ever owned. Another one had a flicker problem which developed in just over a year (I just replaced that one this month) and another burned up a regulator IC after a few years use. The inrush current and transients when you turn on an LED light can destroy cheap components over time just like any other bulb.

I have found the ones with ribbed cooling fins to work better, but it is hit and miss as to which manufacturer and model you should get as there is enough variation between manufacturing runs due to corners getting cut without warning.

LED lighting – just like SSD (Solid State Drives) it promises to be a huge leap in reliability but a manufacturer always seems to figure out a way to pinch pennies and wreck that longevity gap. (some SSDs used to have just as high or an higher a failure rate than conventional hard drives until the manufacturers got their failure modes worked out.

Don’t get me wrong – I like LED lighting and have been converting over for years, but be careful in your research.

And on that point there are a few good things left about incandescents in that they are better suited for accurate depictions of work in art galleries and museums. This is known as excellent color rendition, and they are typically rated around 98 % + while LEDs are typically in the low 80s. Also, they generally make better point source lighting which increases contrast when examining objects in fine detail. Finally, you have a warmer cast to the light which may be suitable for setting certain moods. (I have studied a little about lighting design)

I agreed that LEDs lighting is generally good and the direction we should go for MOST applications. But not all LED bulbs are created alike and you should consider the actual reliability based on manufacturer, model and manufacturing run. I have some that have lasted for years, another one didn’t even make it a month. (from a manufacturer / model that used to be good) Currently, I prefer to buy from a local store than online as it is easier to return if you get a dud. Incandescents and CFLs still have a very limited niche and I would only use them if you have a specific reason to do so. (and I do)

Bear in mind that the biggest jump in energy efficiency was from incandescents to CFLs, (a factor of 4) but from CFLs to LEDs the jump is not quite as dramatic. (a factor of 2) Also, the weak link in any LED bulb is the AC/DC converter built inside – ribbed heat sinks help a lot and I don’t think it hurts to look for Energy Star rated bulbs. Otherwise, you can wind up with an LED bulb that does not even have nearly the longevity of an incandescent. I have seen it too many times.

From my experience, the Cree models sold at Home Depot are pretty decent and the ratings I see on there look promising. Just hang on to your receipt and look at the color temperature in Kelvin (not the same as actual temperature) so that you can “color match” your lights. From 2700 – 3200 K has a yellow cast with the “hotter” temperatures like 4500 K and up looking more and more bluish white. Cooling ribs on the side promote longer life.

I prefer incandescents for the bathroom, but the higher temps for task lighting and elsewhere. If you have a mismatched set in a ceiling fan for instance, it will be pretty obvious.

I will keep you posted if I find a really reliable brand, but manufacturers can go from great to crappy pretty quick. (what you bought last year may no longer be that reliable)

From an EMF standpoint, the lower current draw of an LED is attractive as that also lowers the magnetic field intensity. However, there is more potential noise induced in the electrical wiring which can cause unexpected problems and anomalies with other electronic equipment.

A comment I found online from a neighbor (NextDoor.Com) related an issue with the Internet connection of a residence that malfunctioned due to this noise:

“I did have that problem before and after MANY different visits it was discovered that the box on my house was close to my security lights. I had put the new CFL/LED lights in. That seemed to interfere. They moved my box and things have been fine since.”

Typical EMF & RF Sources in the Home

Homes have several potential sources for high EMF and RF sources including:

  •  External high voltage power lines (both primary and secondary feeders) which can produce elevated levels – particularly in densely populated urban areas / cities such as Dallas, Fort Worth, Houston, Austin, etc. or in homes near utility easements
  •  The main 120/240 volt feed entering the home through the power drop
  •  Breaker boxes
  •  Fluorescent lights (some also have an RF component as well which can cause equipment interference)
  •  High output halogen lamp banks such as those used in track lighting (uses a lot of current)
  •  Appliances with motors or heating elements (washers, dryers, refrigerators, etc.)
  •  AC Adapters
  •  Wiring Errors
  •  Outside Air Conditioning Compressors and Pool Equipment
  •  Wireless Routers, Cell Phones, Bluetooth and Cordless Phones (radio frequency only)
  •  Smart Meters (but fairly low level)
  •  Dimmers (though the range tends to be very short, but I have seen them wreak havoc with sensitive electronic equipment)

The focus should primarily be in areas exposed to EMFs where occupants spend 90 % of their time or greater – this sample schematic gives examples.

Focusing on areas where people spend 90% of their time

Focusing on areas where people spend 90% of their time

LFE means Low Frequency Electromagnetic – this is the typical ELF (Extremely Low Frequency) band for 60 Hz AC power

Typical Low Frequency 60 Hz EMF

Typical Low Frequency 60 Hz EMF Sources

Higher frequency RF sources in the home including wireless routers, printers, laptops and other portable cell phone / tablet devices – DECT means Digital Enhanced Cordless Telecommunications

Typical High Frequency RF Sources in the Home

Typical High Frequency RF Sources in the Home