There are some plastics in the unit (specifically in the accessory outlet, screw covers and controller), but plastic material doesn’t off gas until the ambient temperature reaches 212 degrees, which is quite a bit higher than our saunas’ top temperatures.
All saunas are made with some amount of glue. It's impossible (regardless of what a competitor may tell you) to construct a sauna without glue. The difference between brands is where is the glue used and the type of glue used.
Finnmark Designs constructs it's infrared saunas with very little glue within the sauna's cabin. This glue is located behind the cedar tounge and groove slats to hold them in place. The glue used is non-toxic (like most glues). However, our glue goes a step further and is non-toxic up to 250 degrees. Many brands use low grade glue that may be non-toxic when the sauna heats past 120 degrees.
Finnmark Designs contacted an environmental testing facility and spoke with an environmental biologist in regards to testing our sauna for VOC's and any off-gassing material. After examining the interior of our saunas, the biologist did not recommend a full test as the material used was comprised of Western Canadian Cedar and metal components.