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TriField EMF MeterRF, EMF, & ELF Measurement Tools, Accuracy & Calibration

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Test Instruments for Measuring Electromagnetic Fields, Radio Frequencies, ranging from low to very high frequency and including low EMF:

This article explains the accuracy of and calibration methods for a variety of low-cost EMF measuring instruments used for performing electromagnetic field (EMF) or electro-magnetic radiation EMR and radio frequency (RF) field strength measurements to measure RF EMF exposure levels in gauss or milligauss or at other appropriate yardsticks of field strength.

We discusses sources of RF and EMF fields, and RF/EMF measurement error and variation in electromagnetic field strength measurements and we review and make suggestions for using several low-cost RF or EMF measurement devices to determine the instantaneous electromagnetic field or radio frequency field strength exposure.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

Evaluation of and Advice for Using Some Low-Cost Electromagnetic Field Measurement (EMF) Instruments for Consumer Use

Walker EMF measuring instrument (C) Daniel Friedman

Article Series Contents:

Specific ELF measurement tools (power lines, electrical wiring, appliances) are described and their sources listed

at ELECTROMAGNETIC FIELD EMF MEASUREMENT INSTRUMENTS.

Because RF and EMF measurement tools need to be properly chosen to measure the particular type and frequency of RF or EMF signal that is of interest, be sure to also

see EMF RF FIELD & FREQUENCY DEFINITIONS for a simple explanation of different types of radio frequency (RF) and electromagnetic frequency (EMF) types and where they are found.

Separately, RADIO FREQUENCY RF DETECTION METERS describes several low-cost and accurate radio frequency or RF detection and measurement devices suitable for radio, TV, cell towers, cellphone equipment, microwave, and similar signals.

Small absolute health risk from EMF: Most researchers indicate that where a risk is present, the absolute risk level from EMF is likely to be small, and less than other less obscure hazards. (Automobile accidents, trip and fall, fire, and shock hazards, smoking and other health risks.) Consumers should not let focus on a specific emotionally-charged hazard distract them from these other more mundane but more dangerous concerns.

For added confidence in our measurement results, we use two independent measurement instruments - a Safeco™ analog meter and a Walker Scientific™ digital meter.

Both instruments measure magnetic fields which may be generated from power lines, transformers, household wiring, computers, TV's, and other electric devices.

Measurements made by these devices should be considered as a general screening procedure designed to discover the possible presence of magnetic fields in and around the building or site. Such measurements are not exhaustive. Before making decisions involving any significant expense we recommend that additional instrumentation and expertise be considered.

The Walker™ digital meter provides a direct readout of field strengths in gauss or milligauss. The Safeco™ analog meter permits visual observation of field orientation and strength, but requires mathematical computations to develop a final field strength number.

Our staff are not experts in electromagnetic fields.

As the first and currently the only home inspection professional firm to offer this service in our area we have relied on the quality of instrumentation, information and consulting provided by the manufacturer, and field experience at a range of buildings and environments.

 

Accuracy and Calibration of Electromagnetic Field Measurement Instruments

Quite a few electromagnetic field strength metering devices are available to the public, and they're not costly. A typical price for a decent EMF measuring device is less than $200. with some instruments selling at twice that price.

Because some people offering to perform EMF measurement services are not careful about procedure, do not offer sound scientific advice, and may not themselves understand how to examine a property effectively, some consumers may be better off buying their own EMF meter or gauss meter and using the procedures we describe here.

See DEFINITIONS OF GAUSS VS MILLIGAUSS for details about gauss and milligauss and definitions of these terms

Please do not contact us with a request buy EMF or RF measuring equipment. We do not sell anything. To do so would be a conflict of interest for this website. These devices are readily available from many electrical equipment and home inspection equipment suppliers.

Field Calibration of EMF Electromagnetic Field Strength Measurement Instruments

Our standard measurement procedure includes confirming normal instrument operation by measuring a known common field source - the electric meter at each property as well as at a baseline meter. We measure at 1' and 2' distances from the electric meter, typically finding a field strength between 2 and 7 milligauss in those areas.

Calibration of EMF Measurement Instruments With Electric Power Company Instruments for Measuring Electromagnetic Field Strength

we have compared our test measurements of specific sites with those obtained by local electric utility company representatives and have found our measurements and theirs to be in close agreement.

[Measurements made at the same electric meter at the same distances produced results within 7% of one another. Most power utility companies use equipment which is more sophisticated (and costly) than our own and their personnel may have additional training. See AHS Report #I9189105]

Instead of contacting us with a request to perform EMF Electromagnetic or RF Radio Frequency Field Strength measurements, in most cases it is more economical and convenient for a property owner to purchase their own instrument, making measurements under varying conditions. In this series of articles we describe how to make measurements using a consistent approach and using good documentation.

See EMF MEASUREMENT STEP BY STEP for details of how to collect EMF measurement data.

Following good procedure and using instruments properly are two steps towards making accurate, repeatable EMF measurements.

But because the signal transmission for RF sources such as radio, TV, or cell towers, the load on a power transmission line is not under control of an individual property owner, and because the EMF strength varies as the power transmission line load varies, it is important to have an idea of that condition as well when attempting to characterize EMF exposure at a specific location.

In contrast, EMF measurements are quite accurate and repeatable at other EMF sources such as close to electrical appliances and service entry cables.

Please do not contact us with a request buy EMF or RF measuring equipment.

We do not sell anything. To do so would be a conflict of interest for this website. These devices are readily available from many electrical equipment and home inspection equipment suppliers.

 

This article describes several low-cost and reasonably accurate EMF measurement devices that are readily available.

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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

Question: which microwave oven leak detector should I buy?

RE-posting from private email: Just wanted to thank you so very much for your kind help with finding a properly working microwave oven leak detector...otherwise I'm basically groping in the dark.
I don't see my reply I sent to you on the website, so I thought I'd send it to you via email.

After having checked out the brands you posted (they were out of my price-range), I did find the Trifield TF2, which was a little less, but still out of my price range.

Then I found this one which had (according to fakespot.com) more than 90% legitimate comments on it on Amazon (which I have never seen before, btw). Are you by any chance familiar with it? Any comments from you (she asked hopefully)?

Meterk EMF Meter Electromagnetic Field Radiation Detector Handheld Mini Digital LCD EMF Detector Dosimeter Tester Counter
https://www.amazon.com/gp/product/B0754VVW4W/ref=ox_sc_act_title_1?smid=A22VY4EFXW0BG&psc=1

Thank You again, - Anonymous by private email 2020/10/06

Moderator reply:

Sorry but I don't have specific review data on the Mertek; There must be a reason that these devices, when sold by reputable companies like Fluke cost 10x as much; I don't know if that's because the costly items are very precise in their readings (which you may not need) or because the very cheap units, like our president, don't actually work worth a darn.

I also don't know what to make of comments on Amazon; that yardstick of quality is too-easily manipulated.

My grandfather Louis used to say

If the price is too good to be true, it may be because it's not true.

Last week, shopping for a 1TB SD card for use in a computer I saw most priced in the $300. range with one for sale for $24. U.S. - that one is a fake and doesn't work. It was too good to be true.

I've written that the strength of typical EM electrical fields falls off as the square of the distance from the appliance or other source. So it's likely that unless you are sleeping with your head in the microwave and keep it running 24/7, there is no measurable health hazard to building occupants where such a device is present.

I advised before that you find a good reason for testing your microwave; it may be cheaper to buy a new one than to get a highly reliable test.

Recommended reading

For readers planning to complete an EMF survey,

see

see also


...

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EMF MEASUREMENT INSTRUMENTS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


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