Electromagnetic Fields in Swiss Homes

Electromagnetic fields in Swiss homes are described with a small set of terms, measured against the NISV limits, and reduced room by room. The vocabulary covers electric and magnetic fields, the frequencies run from the 16.7 Hz of the railways to 5G, and the practical work starts with a measurement protocol before any change is made. What follows sets out the words, the numbers and the steps in the order a household usually meets them.

What does electrosmog mean in a Swiss building?

Electrosmog is the everyday word for the electric and magnetic fields produced by technical installations, and it is not one single thing. A field has a frequency, a strength and a direction, and each of those decides whether it matters in a room. Electric fields come from voltage and are present even when nothing is switched on. Magnetic fields come from current and appear only when a device draws power. Low-frequency fields, below roughly 100 kHz, are tied to the mains and to wiring. High-frequency fields, from about 100 kHz upward, are tied to radio services, mobile telephony and wireless equipment. The Swiss magazine FELDWERK covers this vocabulary alongside the physical basics, and its pages on electromagnetic fields in rooms are written for non-specialist readers who want the terms before the numbers. A measurement report will separate the two field types, because they behave differently and are reduced by different means.

Which frequencies are met day to day?

The frequencies in a Swiss home are few and recognisable. Railway current runs at 16.7 Hz, a frequency specific to the Swiss and some neighbouring networks, and it reaches buildings near tracks and feeder lines. The mains supply runs at 50 Hz, and its harmonics appear on wiring, on rails and on any conductor carrying current. Above that, radio and television services, mobile telephony from older bands to 5G, and the wireless links used indoors occupy frequencies from the low megahertz range upward. The spectrum itself is continuous, from static fields to gamma radiation, but only a narrow part of it is produced by the equipment in a dwelling. Knowing which frequency belongs to which source is what allows a reading to be attributed to a cause rather than to a general feeling.

What are the NISV limits and who sets them?

Switzerland regulates non-ionising radiation through the NISV, the ordinance on protection from non-ionising radiation, which applies to installations such as mobile base stations, power lines and transformers. The NISV sets installation limits that must be met wherever people may stay, and it adds precautionary values for places of sensitive use, including dwellings, schools and hospitals. The international guidance from ICNIRP provides the health-based reference levels that underpin many national systems, while the Swiss precautionary approach goes further in certain cases. The two are not the same instrument and should not be quoted as if they were. A measurement is compared against the limit that applies to the location and the frequency concerned, which is why a value without its context says very little.

How is a measurement protocol carried out?

A measurement protocol is a defined procedure, not a single reading. It states the instrument, its calibration, the frequency range covered, the height and position of the probe, the duration of each sample, and whether the installation was operating normally during the test. Low-frequency magnetic fields are usually recorded over a period long enough to catch load variation, while high-frequency fields are recorded with a meter that resolves the individual services. The result is reported as a value per frequency or per band, with the limit it is compared against. Interpretation follows: a reading below the limit is not automatically a reading without interest, and a reading above a precautionary value is not automatically a health finding. The protocol exists so that two measurements of the same room can be compared, and so that a change made later can be judged against a baseline.

How is exposure reduced room by room?

Reduction is done one room at a time, and the bedroom comes first because it is where people spend the longest uninterrupted hours. The usual order is to identify the source, then to remove it, move it, or distance it. A device that is not needed at night can be switched off at the socket, which removes both its electric and its magnetic field. A router or a cordless phone base can be moved away from the head of the bed. Fixed wiring, risers and meter cabinets cannot be moved, so the bed or the desk is placed at a distance from them instead. In rooms used during the day, the same logic applies with less urgency: keep chargers and small transformers away from the body, and prefer a wired connection where a wireless one is not required. Each change should be followed by a repeat measurement under the same protocol, so that the effect is known rather than assumed. Records kept in this way stay useful after the immediate concern has passed, and they allow a later occupant or a technician to see what was done and what it changed.

What should a household keep on file?

The useful file is short: the measurement protocol, the readings with their dates and conditions, the limits they were compared against, and a note of each change made and its measured effect. Primary sources, the authorities and the standards behind the limits belong in the same file, because they are what a technician or an adviser will ask for. A household that can show a baseline, a change and a second reading is in a stronger position than one that can only describe a sensation. The vocabulary, the frequencies and the limits are the common ground on which that file is built, and they are the same whether the concern is a bedroom, a classroom or a workplace.