Shop for a sauna blanket for more than five minutes and you'll run into the phrase "low EMF." Every brand claims it. Very few explain what it means, how it was measured, or who measured it. This guide is the explainer we wished existed when we were building ours — the units, the standards, and the exact questions that separate a tested product from a marketing sticker.
Why EMF comes up with sauna blankets at all
A sauna blanket is an electric heating element that wraps around your body for half an hour at a time. Anything that runs current produces an electromagnetic field (EMF), and because a blanket sits directly against you — unlike, say, a ceiling light — the sensible question is how strong that field is at the surface where you actually are.
One honest fact up front: no plugged-in device is truly "zero EMF." If it heats, it draws current; if it draws current, it produces a field. The meaningful questions are how much, measured how, and compared against what.
The units you'll see — and how brands use them
Milligauss (mG) measures magnetic field strength. It's the number most sauna blanket brands quote — "0.5 mG," "under 2 mG" — usually from a handheld consumer meter. Handheld readings are better than nothing, but they vary enormously with where you hold the meter, at what temperature the blanket is running, and which meter you bought.
Percentage of a reference limit is how accredited labs report. Instead of a raw number, the lab measures the field across the whole device under standardized conditions and expresses it against an internationally agreed exposure reference level. A result like "0.2% of the reference limit" means the measured field was five hundred times below the level the standard treats as the ceiling.
What EN 62233 is
EN 62233 is the international standard specifically for measuring the electromagnetic fields of household appliances used near the human body — exactly the category a sauna blanket lives in. A test to this standard is done by a laboratory under controlled conditions: defined measurement distances, the device at full operating power, calibrated instruments. It's the difference between a physical exam and telling people you feel fine.
The four questions to ask any sauna blanket brand
Whether you buy from us or anyone else, these four questions sort the field quickly:
1. Who did the testing? "Internally tested" and "tested with a meter" are self-report. An independent, accredited laboratory has its name on a report and a reputation to protect.
2. To which standard? If a brand can't name the standard, there isn't one. EN 62233 is the relevant one for body-proximate appliances.
3. At what power? A blanket idling at its lowest setting produces a fraction of the field it does at maximum temperature. Credible tests run at full operating power.
4. Can I see the report? This is the question that ends most conversations. A brand with a real report will show it to you. A brand with a sticker will change the subject.
Where Solfold stands
Our blanket is tested by an independent accredited laboratory to the EN 62233 standard, at operating power. The measured exposure came in below 0.2% of the international reference limit. And the fourth question is our favorite one: email hello@solfold.com and we'll send you the complete lab report — every page, not a summary graphic.
We publish it this way because "trust us" isn't a spec. Receipts are.
The bottom line
"Low EMF" without a standard, a lab, and a report is a font choice. If you're comparing blankets, ask the four questions and watch what happens. And if you'd like to see what a real answer looks like, our Solfold Infrared Sauna Blanket page states the numbers, and the full report is one email away.
Curious about the practical side? Read our first-session guide or see how the costs compare to a sauna room. More questions — our FAQ covers shipping, returns, and the pre-order details.