When selecting a sauna, prioritize wood quality, specifically Canadian Hemlock, Red Cedar, or Spruce, as these are resistant to warping and splitting under high heat. For Infrared Saunas, ensure the heating elements are Low EMF (Electromagnetic Field) carbon or ceramic heaters to meet health safety standards. For Traditional Steam Saunas, verify the kilowatt (kW) rating of the heater matches the room volume (typically 1kW per 30-45 cubic feet) to ensure efficient heating. Additionally, look for tempered safety glass with a thickness of at least 6mm to 8mm to prevent thermal breakage.