When people talk about electromagnetic pollution, they usually think of Wi-Fi, 4G/5G or high-voltage power lines. Yet a far more discreet phenomenon hides right inside the wiring of your home or office: dirty electricity.
What exactly is it?
The European electrical grid is meant to deliver a perfectly regular alternating current at 50 Hz. In reality, this clean signal is increasingly "polluted" by high-frequency disturbances: harmonics (multiples of 50 Hz, such as 150 Hz, 250 Hz, and so on) and brief pulses called transients. These disturbances, generally found between 2 kHz and several MHz, are superimposed on the normal current and travel along the same wires as your household electricity.
This is a phenomenon well known to electricians and engineers, who more soberly call it conducted electromagnetic interference (EMI) or power quality distortion, concepts governed by real technical standards (EN 50160, IEC 61000). The term "dirty electricity" comes more from the world of building biology and environmental health, but the physical phenomenon it describes is very real.
Where does it come from?
Dirty electricity does not have a single origin: it is the cumulative result of a great many modern electronic devices.
Inside a building, the main culprits are "non-linear load" devices, meaning ones that don't draw current smoothly but chop it up electronically:
- Switch-mode chargers and power supplies (smartphones, computers, internet boxes)
- LED bulbs and energy-saving lamps, dimmer switches
- Variable-speed drives (motors, induction hobs, appliances)
- Inverters, whether for solar panels or for computing equipment
From outside, the distribution network itself carries a share of this pollution accumulated across all connected buildings, to which smart meters, neighbouring solar installations or electric vehicle charging points can add.
The more electronics a building contains, the more likely the electricity circulating in it is to be "dirty".
How is it measured?
This type of pollution cannot be detected with a standard electromagnetic field meter: it requires an instrument specifically designed to pick up these intermediate frequencies, between ordinary 50 Hz and radiofrequencies. This is one of the strands we build into a complete electromagnetic audit, alongside traditional electric and magnetic field measurements.
A typical professional protocol starts with a baseline measurement in several rooms, distinguishes internal from external sources by switching circuits off one by one, then compares the level measured before and after installing any filter, checking that no resonance is instead making the signal worse.
And what about health?
The electrical phenomenon itself is real and measurable: that is not a matter of opinion. However, the health claims sometimes associated with it (cancer, diabetes, electromagnetic hypersensitivity) remain controversial and are not the subject of scientific consensus. Debating them is not the purpose of this article: our role is first and foremost to understand, measure and, where needed, reduce this type of electrical pollution in your environment.
Sources
- EN 50160, standard on the voltage quality supplied by public distribution networks
- IEC 61000, series of standards on electromagnetic compatibility
- de Vocht & Olsen, Systematic Review of the Exposure Assessment and Epidemiology of High-Frequency Voltage Transients, Frontiers in Public Health (2016)
- World Health Organization, fact sheet on electromagnetic hypersensitivity (2005) and "Radiation: Electromagnetic fields" summary
- Anses, opinion on electromagnetic hypersensitivity (2018)
- SCENIHR, opinion to the European Commission on electromagnetic fields (2015)
- Superior Health Council (Belgium), opinion no. 8081 on exposure to low-frequency electromagnetic fields