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This paper discusses the basics of how we can reliably measure the level of electromagnetic radiation or electromagnetic fields (EMF). Detailed EMF survey procedures are provided later in this article series at Recommended EMF Measurement Procedure. Readers who need to measure EMF themselves or who intend to hire someone to do so should also be sure to review our more detailed EMF measurement procedures at Electromagnetic Radiation Field EMF SURVEY Procedure and also see EMF Survey Worksheet - Excel Spreadsheet and EMF Survey Worksheet - Sample & Explanation. Our page top photo shows a Safeco™ electromagnetic field measuring instrument. This the EMF readings that this instrument obtains are position sensitive - where you point it makes a difference even in the same spot.

© Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

The Basics of Measuring Electromagnetic Field EMF Exposure Levels

Hiring Someone to Measure Electromagnetic Field Strengths

If a building owner or occupant is concerned about EMF levels at a property, the local power company may be willing to perform site measurements at no charge.

Independent experts provide thorough site profiles for fees ranging from $500. to $1,000. and include extensive consulting which helps protect realtors from future liabilities and can calm inappropriately frightened buyers or sellers.

Explicit, competent, documented measurements are more reliable than unsubstantiated opinions based on visual observation and fear. No one should be cavalier about children's health, but keeping risks in perspective serves everyone and helps assure that parents focus on the big risks first.

See EMF Procedures & Causes of EMF Measurement Error & Variation .

Making Your Own Electromagnetic Field Strength EMF Measurements

(If you're simply curious about finding and measuring local EMF strengths around a home, an alternative might be to simply purchase an inexpensive electromagnetic field strength measuring device.

But before dashing about recording numbers, it is important to understand both the peculiarities of EMF field strength meters and the peculiarities of the size, shape, pattern, and time variation of electromagnetic fields themselves.

Suggestions for using some sample EMF measuring instruments and a discussion of the sources of error and variation in EMF measurements are discussed in more detail at our Electromagnetic Radiation Field EMF SURVEY Procedure located at this website.

At Evaluation of Low-Cost EMF Instruments such as the TriField EMF and RF meter shown here we show several different types of EMF measuring instruments and discuss their properties.

Please do not contact us to buy 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.

Instead of contacting us with a request to perform EMF Electromagnetic 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 Recommended EMF Measurement Procedure 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 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 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. See Evaluation of Low-Cost EMF Instruments where we describe several low-cost and reasonably accurate EMF measurement devices that are readily available.

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Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
ENVIRO-SCARE, EMF & Property Values
ENVIRO-SCARE Defined, Effects
ENVIRO-SCARE Effects on Property Values
EMF MEASUREMENT PROCEDURES
EMF SURVEY PROCEDURE - Details
  Introduction to EMF Measurement
  EMF/EMR Measurement Procedure Overview
    EMF Variability
    Electrical Utility Workers & EMF Exposure
    EMF Instrument Sensitivity & Accuracy
    EMF Polarity & Shape Affect Measurements
    Distance from the EMF Source Affects Strength
    Time of day & Season Affect EMF Strength
  Local EMF Sources May Exceed Power Line Strength
  Recommended EMF Measurement Procedure
    Outside EMF Measurements
    Outside EMF Measurement Documentation
    Indoor EMF Measurements
    Other Indoor EMF Measurement Targets
    Workplace EMF Measurements
  EMF Measurement Documentation Details
  EMF Measurement Instrument Use
    Definitions of Gauss vs Milligauss
    Position-sensitive EMF Instrument Readings
  Interpreting Electromagnetic Field Strength EMF Survey
  Evaluation of Low-Cost EMF Instruments
    Accuracy & Calibration of EMF Instruments
    Calibration of EMF Instruments in the Field
    Calibration of EMF Instruments by Electric Company
  EMF ELF Instruments
    F.W. Bell Model 4060 ELF Meter
    Safeco™ analog EMF ELF EMR meter
    Walker Scientific ELF-50D™ Digital EMF Meter
References for Electromagnetic Fields and Cancer
WORKSHEET for EMF MEASUREMENTS
WORKSHEET for EMF MEASUREMENTS - Example
WORKPLACE EXPOSURE to Electromagnetic Fields

More Information on Building Diagnostic Inspections and Repairs

• Electric Power Lines, Electromagnetic Fields, Cancer Risk, & "Enviro-Scare" - The Normal Curve Cycle of Public Fear About Environmental Issues - online document by DF
• A Procedure for Measuring EMF electromagnetic fields online document by DF
• Electromagnetic Fields in the Workplace good NIOSH document, links to other NIOSH docs.
• Basketball Mold Syndrome - BBMS- sudden attention to old clues in buildings makes them seem brand new to some observers
• Consumer Product Safety Commission, 800-638-CPSC.
• US Environmental Protection Agency, Office of Pesticides and Toxic Substances, TSCA Assistance Office (TS-799), 800-424-9065 or 202-554-1404.
• "Evaluation of Potential Carcinogenicity of Electromagnetic Fields," EPA Report #EPA/600/6-90/005B October 1990. EPA: 513/569-7562.
• "Biological Effects of Power Frequency Electric and Magnetic Fields" background paper, prepared as part of OTA's assessment of "Electric Power Wheeling and Dealing: Technological Considerations for Increasing Competition," prepared for OTA by Indira Nair, M. Granger Morgan, H. Keith Florig, Department of Engineering and Public Policy, Carnegie Mellon University, Pittsburgh, PA 15213
• "Biological Effects of Power Line Fields," New York State Powerline Project. Scientific Advisory Board Final Report, July 1, 1987.
• "Extremely Low Frequency (ELF) Fields," Environmental Health Criteria 35. World Health Organization, Geneva, 1984.
• "Electric and Magnetic Fields at Extremely Low Frequencies: Interactions with Biological Systems. In: Non ionizing Radiation Protection, World Health Organization, Regional Office for Europe, Copenhagen, 1987.
• "Electric and Magnetic Fields from 60 Hertz Electric Power: What do we know about possible health risks?," Department of Engineering and Public Policy, Carnegie Mellon University, Pittsburgh, PA 15213 1989.
• "Electromagnetic Fields Are Being Scrutinized for Linkage to Cancer," Sandra Blakeslee, New York Times, Medical Science section, April 2, 1991.
• Environmental Concerns in Buildings, hazards: allergens, asbestos, brownfields
  - above ground or buried oil storage tanks,
  - A Procedure for Measuring EMF electromagnetic fields,
  - Electric Power Lines, Electromagnetic Fields, Cancer Risk, & "Enviro-Scare" - The Normal Curve Cycle of Public Fear of Environmental Issues
  - toxic gases & odors, IAQ, lead paint,
  - toxic mold inspections,
  - mold test kits - how to send a mold sample to our lab using an inexpensive and superior method - radon, sick buildings, UFFI (urea formaldehyde foam insulation),
  - sewage septic backup contamination testing & cleanup
  - water testing for bacteria, lead, etc.

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