The latest difference of infrared saunas is what my site focuses on. I have edited this page to focus more on the third generation saunas.
The earlier generations had high EMF output and had just a little bit of the Far infrared range of heat, just enough to claim the sauna as a far infrared sauna. Mainly they were the rod types. Many people still use the rod type as the rods don't emit EMF like the carbon heaters. Now the carbon heaters have finally came up with a way to build a negligible to low emf sauna heater. Some of the 3rd Gen saunas are now shielded for EMF all the way to the wires and electronic components.
NOTICE:
As of 2013, I do not sell any saunas that have high EMF output. There are now EMF free heaters.
Note: Their are some saunas that have low emf but they are not the carbon panel saunas but the carbon paper saunas, baked on. I always test the EMF to see if its a true 3rd generation sauna. If it is not ETL rated I know for sure. The 2nd generation saunas had around 20 to 25 until now.
The early generations when infrared saunas first came out about 20 years ago had around 80 to 100 mili gauss in the late 1990's. The cheap saunas usually don't have the components to rid the EMF. Also, there are some companies that put those Cell phone stickers that block EMF but this is more temporary and they do pass the EMF test at first but just like the manual says, the stickers need to be replaced in the future, usually a year. Some companies are adding dual heaters back to back like EMF free heaters in this video below I found. This is not the only company that now has EMF free and low EMF heaters. One sauna company claims they were the "pioneers" and were the first to eliminate EMF 100% but another also claims they were the first. I don't know who to believe. The cost of the EMF free heaters where they put a dual carbon panel makes the sauna super expensive. The stickers can also help block the EMF but are only temporary.. There are come companies that infuse an entire roll of aluminum foil that helps transmute the EMF. I have samples which I can send anyone. I paid several thousand dollars for this role of aluminum foil. It doesn't block the EMF but transmutes it. For the non emf heaters, the ion output mixed with the infused Reynolds Wrap, gives the body a tingly feel. Anyone I ever showed it to feels it within 2 seconds. If you put a chili pepper on the aluminum foil it makes it taste milder like a bell pepper. If you put salt on the foil, it takes all the saltiness out of the salt within 1 minute. I will send anyone who wants to learn about this foil a free sample as long as I still have some. If you are reading this I probably still have it. I put a quarter size piece of foil next to my battery on my cell phone and its made a night and day difference. I hurt my wrist in jiu jitsu class and to get rid of the pain I held my phone over my wrist and the pain went from an 8 to a 2 in just one minute. I am not making this up. I will send anyone a quarter size piece of this foil. I cannot order more but I have enough to last me for a while. What's nice is that the foil can pick up the ion output the heaters give out and the infrared rays from the heaters acts as a carrier wave. I put about 2 stickers on every heater. It gives the sauna an entirely different feel.
Test your sauna with 30 dollar Dr. Gauss meter.
This will tell you if the EMF is in the red zone or the safe range. I have demo loaners if anyone wants to borrow one.