Don't get caught in this trap. Unless you live on the top of Mt. Everest you are already exposed to considerable emf's just from being in the modern world.

FIR saunas are really good, high emf or not. You only spend 1/2 hour in there and the benefits will outweigh any perceived negatives at this point.

Keep hydrated with electrolyte drinks and start slow with the saunas.

People with emf sensitivities are probably metal poisoned, and FIR (Far-Infrared-Sauna) saunas get metals out.

Don't ever go by reviews when selecting treatments: always test things out for yourself with direct experience. You can go to one of those tanning/beauty places to try one out once or twice before purchase.

I would consider using Ozone which you can also use as in a steam sauna* which will detox you. You can also administer ozone in other methods. Ozone is extremely antimicrobial as well with reports of Lyme patients getting help. Ozone is one the best therapies I used.

A Lyme patient's story:
https://youtu.be/4OwnT9XrCMY

I have read people using infrared lamps you can purchase at Lowe's which is a PAR38 bulb. May not be as good but it is cheap.

https://www.amazon.com/Sylvania-13836-PAR-38-Infrared-Heat/dp/B00901J6AK

*you don't need to buy the expensive sauna cabinet, you can use the cheapo ones (<$150).