By Matt Justice. Based on seated-position EMF measurements of 40+ infrared saunas over 8+ years. Last updated: October 2026.
Short answer: a truly low EMF infrared sauna reads near 0 V/m for electric fields and about 1 to 2 mG or less for magnetic fields where you actually sit, with the heaters running. In my testing, Rocky Mountain, Heavenly Heat and Clearlight rated as true low-EMF saunas. The Sunlighten Amplify V2 is close. Nothing I have tested under $2,000 is low EMF, no matter what the box says.
Most “low EMF” claims only cover magnetic fields, or come from a lab that tested one heater on a bench. Below are the real readings from fully assembled saunas, measured where your body sits, including the electric fields most companies leave out.
Low EMF infrared saunas: my measured readings
Readings are what I called out on camera with the heaters on, and each cell names the position when it was not the seat. I used a TriField TF2 in the side-by-side test, for the photo readings (Rocky Mountain, Heavenly Heat, Clearlight Sanctuary 1 and Durasage), and in the blanket test; the other videos do not name the meter. Results apply to the units I tested, not every model or later revision from a brand. Magnetic fields are in milligauss (mG), electric fields in volts per meter (V/m).
| Sauna | Magnetic field | Electric field | My rating |
|---|---|---|---|
| Rocky Mountain 1-person | 0.1 mG seated, heaters warmed up (about 1 mG at the knee and bench in my side-by-side test) | 0 V/m seated, heaters warmed up | A |
| Heavenly Heat Eco Mini | 0.8 mG seated (peak 1.0); about 1.7 mG seated in my earlier video spot check | 0 V/m seated (peak 2); about 1 to 3 V/m in my earlier video spot check | A |
| Clearlight Sanctuary 1 | 0.5 mG seated; 0.6 mG at the knee facing the front full spectrum heater | 0 V/m seated and at the knee; 36 V/m with the meter held right at the front heater guard | A |
| Clearlight Premier IS-2 | Ultra low in my original Premier IS-2 test (2019) | Low in the same test | A |
| Radiant Health Pause 2 | 0.1 to 0.4 mG at the backrest; 0.2 mG in front of the red light panel (essentially 0 in my side-by-side video) | 0 V/m at the backrest and in front of the red light panel; about 1 V/m near the back heater (grounded heat shields) | A, but recalled; affected units must not be used until the approved repair is installed |
| Sunlighten Amplify V2 | 0.2 mG at the knee facing the front heater (negligible at the knee in my video) | Under 100 V/m seated with the LED lights off (under 150 V/m with them on); about 150 to 200 V/m near the heaters | B |
| LifePro RejuvaCure Duet (2-person) | About 10 mG seated (7 to 16 around the bench, backrest and walls) | 150 to 300 V/m seated (417 V/m at the floor) | Not low EMF |
| LifePro RejuvaCure 1-person | Higher than the Costco sauna I tested in some spots (no number recorded) | About the same as the Costco sauna I tested (no number recorded) | Not low EMF |
| Costco Dynamic 1 to 2 person | Under 1 to 3 mG; 3 to 6 mG hot spot at the backrest | 300 to 600 V/m, some spots over 1,000 | Not low EMF |
| Durasage portable infrared sauna tent (sold on Amazon) | 0.2 mG at the neck opening | 975 V/m to over 1,000 V/m (past the meter’s range) inside near the back heater panel; 80 V/m at the neck opening | Not low EMF |
| HigherDose sauna blanket (2020 test) | Under 0.5 mG | Not mitigated (no number called out); body voltage 18 to 31 V while running | Not low EMF |
Same meter, two saunas
These are photos of my TriField TF2 screen. The first rows are low-EMF wooden cabins: the Rocky Mountain one-person after it warmed up, the Heavenly Heat Eco Mini, the Clearlight Sanctuary 1 and the Radiant Health Pause 2. The last two rows are a Durasage portable sauna tent sold on Amazon.
Rocky Mountain one-person
Heavenly Heat Eco Mini
Clearlight Sanctuary 1, seated
Clearlight Sanctuary 1, front full spectrum heater
Full spectrum heaters usually add some EMF. Right at the guard of the Clearlight front heater the meter read 36 V/m, but at the knee, where your body actually is, it read 0 V/m.
Radiant Health Pause 2 (now under a CPSC recall; do not use an affected sauna until the approved repair is installed)
Durasage portable sauna tent, inside near the back heater panel
Durasage portable sauna tent, at the neck opening
All five have low magnetic fields. The difference is the electric field where your body sits: 0 V/m in the Rocky Mountain, Heavenly Heat, Clearlight and Radiant Health, and 975 V/m to over 1,000 V/m inside the Durasage. A magnetic-only reading would make them all look the same.
At the heater vs. where you sit
The full spectrum (quartz halogen) heaters in the front of a lot of saunas give instant heat and a hotter surface, and in every brand I have tested they read higher right at the grate. The question is whether that field reaches you. Some do, some don’t, so I measure twice every time: once with the meter pushed into the heater grate, and once at my knee in the seated position.
Clearlight Sanctuary 1
Rocky Mountain one-person
Sunlighten Amplify V2
In all three, the magnetic field at my knee was under 1 mG, even though the heater itself read 10.9 to 67.5 mG. The Rocky Mountain’s front heater also read 0 V/m on electric fields right at the grate. That is why a reading taken against a heater, whether a brand or a competitor posts it, tells you very little on its own.
I also don’t like saunas that only have these heaters. They put out a lot less far infrared in the 5 to 10 micron range, so I want to see far infrared emitters in the sauna too.
See my best infrared sauna rankings for how these saunas compare on heat, build quality and price, not just EMF.
What “low EMF” should actually mean
EMF is plural: electromagnetic fields. A sauna can produce four things worth measuring:
- Magnetic fields (mG): created by current flowing through the heaters and wiring. This is the only number most brands show you.
- Electric fields (V/m): created by voltage, present whenever the heaters are powered. This is where cheap saunas fail, and where most brands go quiet.
- Body voltage: how much voltage your body picks up while you sit in the field. In my 2020 blanket test, the wooden cabins we checked in the other room read under 1 V, while the HigherDose blanket read 18 to 31 V running.
- RF (radio frequency): from Bluetooth, Wi-Fi and app controls. Not every sauna has it, but if yours does and it sits next to a bedroom wall, it may keep transmitting when the sauna is off.
My standard is simple: as close to nothing as possible at the point of body contact, because that is where you sit. Your phone and your appliances emit EMF too, but you do not sit inside your dishwasher three or four nights a week for 15 or 20 years. With a sauna, the exposure adds up hours at a time.
My EMF rating scale
- A class: electric fields at or near zero (under 20 V/m) and magnetic fields around 1 to 2 mG or less at the seat.
- B class: low magnetic fields and electric fields under 100 V/m in the seated position. This is the minimum for a premium sauna to make my list.
- Not low EMF: electric fields in the hundreds of V/m, or magnetic fields around 10 mG or more at the seat.
Read more about how I score saunas in my review standards.
Why most “low EMF” claims fall apart
They only show magnetic fields
The Costco Dynamic sauna is a good example. Its magnetic fields improved a lot: about 70 mG at the backrest on the unit I tested six years earlier, versus 2 to 3 mG on the newer one. Members of my Facebook group posted those readings as proof it is low EMF. But when I switched the meter to electric fields, the seated position read 300 to 600 V/m and some spots went past 1,000 V/m, the top of my meter. Half the EMF was never shown.
They point you to a lab report on one heater
Many brands send a single heater to a lab, hang it on a test bench, and publish a nice PDF. Your sauna has six or eight of those heaters, plus a power supply, a control panel, lighting and wiring in the walls. Should you multiply the lab number by the number of heaters? Nobody says. That is why I test the whole sauna, assembled and running.
Cherry-picked hot spots go both ways
Every heater has a power connection on the back, and if you hunt for that exact spot with a meter you will find a spike in any sauna, including the best ones. That works both ways: a competitor can screenshot a hot spot to make a good sauna look bad, and a brand can hold the meter in a quiet spot to make a bad one look good. What matters is the reading where your body actually is, for both magnetic and electric fields.
What makes a sauna truly low EMF
The saunas that read near zero on electric fields have grounded heaters or grounded heat shields. In my side-by-side test, the Radiant Health’s grounded heat shields read zero on electric fields even with the meter right up on them, and the Rocky Mountain’s grounded full spectrum front heater is why I rated it a true low-EMF sauna. Full spectrum heaters almost always add some EMF, so look for ones that are grounded, and check them at the knee and shin, not just the backrest.
Nothing under $2,000 is low EMF
I have tested a lot of budget saunas, and none of them pass on EMF. The LifePro Duet read about 10 mG and 150 to 300 V/m. The Costco Dynamic read 300 to 600 V/m. Many Amazon and big-box saunas peg my meter at 1,000 V/m. That does not make them useless: if EMF is not your priority and you just want to sweat, the LifePro one-person is still the best performer I have found in that price range. It beat the Costco sauna because the heater layout is better. Build quality isn’t perfect in either one, but the LifePro one-person performed well in my sessions. Just do not pay extra for a “low EMF” label in this tier.
If you need low EMF on a tight budget, a DIY build gives you control over every component. My DIY infrared sauna course shows you how. For portable options, see my portable sauna guide and my sauna blanket EMF test.
How to test your own sauna for EMF
- Use a meter that reads both fields. I use a TriField TF2 for magnetic and electric fields on camera, and other meters for RF and body voltage in my formal reviews. No single meter measures everything perfectly.
- Check the background first. Take readings outside the sauna with it off, so you know what the room already has.
- Turn every heater on full and let the sauna warm up for a few minutes.
- Measure where your body sits: backrest, seat, behind the knees, shins, feet and floor. Do not judge the sauna by the spot right on a heater connector.
- Hold the meter away from your body for electric fields. Your body picks up voltage and will push the reading up if you are touching the meter in the field.
- Isolate the lights. LED strips and low-voltage lighting can trick the meter. Turn them off to see what the heaters alone are doing.
- Record video so you can compare and share. If you post it in our community, include the meter, setting and position.
Questions to ask a sauna company before you buy
- What are the electric field readings (V/m) in the seated position, with all heaters running, in a fully assembled sauna?
- Are the heaters grounded or shielded for electric fields?
- Is the published EMF report on the whole sauna or on a single heater?
- Does the sauna have Bluetooth, Wi-Fi or app control, and can it be fully powered down?
- If I measure higher than you advertise, what is your return policy?
A company that sells on low EMF should be able to answer every one of these. If they send you to a PDF or tell you your phone emits more EMF, that is your answer.
Frequently asked questions
What is a low EMF infrared sauna?
One that measures low on both magnetic and electric fields in the seated position with every heater running. My bar is near 0 V/m electric and about 1 to 2 mG or less magnetic. A sauna that only shows low magnetic fields is not a low EMF sauna.
What is the best low EMF infrared sauna?
In my testing, Rocky Mountain, Heavenly Heat and Clearlight all rate A class. Radiant Health measured the lowest of all, but those saunas are under a CPSC recall, and my buying recommendation is on hold while I evaluate the approved repair. The Sunlighten Amplify V2 rates B class.
Are cheap infrared saunas low EMF?
Not in my experience. Every sauna I have tested under $2,000, including Costco and LifePro models, measured in the hundreds of volts per meter for electric fields.
Is a lab report proof that a sauna is low EMF?
No. Many reports test a single heater on a bench. A real sauna has several heaters plus wiring, a power supply, a control panel and lighting, so the only meaningful test is the assembled sauna, measured where you sit.
Do full spectrum saunas have higher EMF?
Full spectrum heaters almost always add some EMF. Grounded ones can still read near zero at the body, like the front heater in the Rocky Mountain. Check readings at the knees and shins, not just the backrest.
Is a TriField meter good enough to test a sauna?
A TriField TF2 is a good starting point because it reads both magnetic and electric fields. No single meter measures everything, so for RF and body voltage you need additional meters.
Are sauna blankets low EMF?
The ones I tested were low in magnetic fields but did not mitigate electric fields, and body voltage read 18 to 31 V while running. See my sauna blanket EMF test for details.
Ask about a specific sauna
Wondering about a model I have not listed? Post it in the Certified Saunas Community on Facebook or on r/CertfiedSaunaReviews, and watch my EMF tests on YouTube. Related reading: infrared sauna benefits and risks and the Radiant Health recall update.
Sources and test details
Every reading on this page comes from my own testing. Most were taken with a TriField TF2, which reads magnetic fields (mG) and electric fields (V/m). The 2020 sauna blanket test also used a Gigahertz meter and a body voltage meter.
- Heaters on and fully warmed up before measuring, in every sauna on this page.
- Saunas fully assembled, and portable tents set up as sold.
- Seated readings are taken where your body sits: at the backrest, on the bench and at the knee facing the front heater. Readings taken against a heater are labeled that way.
- Numbers come from photos of the meter screen or from what I read out on camera. If I didn’t record a number, the table says so.
- Each model is measured on its own. I don’t carry a reading from one model or size over to another.
- Older tests are dated. The Clearlight Premier IS-2 test is from 2019 and the HigherDose blanket test is from 2020, so current models may read differently.
- These are measurements, not health claims. A low reading doesn’t prove a sauna is safe or that it will improve your health.
Disclosure
Some links on this page are affiliate links, so I may earn a commission if you buy through them, at no extra cost to you. Commissions do not change my readings. Sauna models change, so confirm current specs and EMF details with the company before you order.
