Primer
Start here.
Five short sections that give you the vocabulary to read the primary literature without a physics degree.
01
What is an electromagnetic field?
An electromagnetic field (EMF) is any region of space where electric and magnetic forces interact. They are produced by anything that moves electric charge — power lines, appliances, radios, mobile phones, Wi-Fi routers, and cellular base stations. Fields are characterized by their frequency: from extremely low frequency (ELF, 50–60 Hz from mains power) up through radiofrequency (RF, from kHz to GHz).
02
The non-ionizing spectrum
Everything discussed on this site sits in the non-ionizing part of the spectrum — below the energy needed to knock electrons off atoms. That means the classical mechanism of ionizing radiation (like X-rays) does not apply. Research on biological effects therefore focuses on non-thermal mechanisms: oxidative stress, voltage-gated calcium channels, blood-brain barrier permeability, effects on cellular signalling.
03
How exposure is measured
RF exposure is often expressed as specific absorption rate (SAR, W/kg) or as electric field strength (V/m) or power density (µW/m²). ELF magnetic fields are measured in microtesla (µT) or milligauss (mG). Guideline limits from ICNIRP are designed to prevent short-term thermal effects; many researchers argue non-thermal effects require lower limits.
04
Common everyday sources
Mobile phones and cordless (DECT) phones held against the head; laptops and tablets on the lap; Wi-Fi routers, particularly in bedrooms; smart meters; wireless earbuds; cell-tower base stations; overhead power lines and household wiring carrying high-frequency transients ('dirty electricity').
05
How to read a study
Ask three questions: (1) What was the exposure — real-world level, or well above ICNIRP limits? (2) What was the outcome — a biomarker, a symptom, a tumor? (3) What was the study type — a blinded human trial carries more weight than an in vitro assay, though both matter. This library tags each entry so you can filter accordingly.