Wood Comparison
TheraSauna® is made with non-toxic and non-allergenic Aspen Hardwood
Infrared energy heats objects (like your body and the inside wood of the sauna) directly and penetrates up to 2 inches below the surface. Cedar and redwood contain a natural insecticide within the wood called turpines. When these naturally occurring oils within the wood are heated, they gas off a substance called cedrine. Cedrine attacks the central nervous system of insects and kills them. It can also cause vomiting and convulsions in humans. TheraSauna® is made of Aspen, which is a clear wood grown at elevations where the trees do not produce an insecticide. Aspen is 99% non-toxic and non-allergenic.
Health Effects Reported with Various Types of Woods 
| Wood Type | Found | Use | Health Effects |
| Alder (common, black, red) |
Europe, North America (red) Western Asia |
Toys, general turnery, broom and brush backs | Dermatitis associated with black alder, no reports with red alder, decrease in lung function (red alder) |
| Aspen | North America | Furniture, strandboard, pulp and paper | No health effects reported |
| Beech | Europe | Furniture, bobbins, brush backs, handles, domestic woodware, flooring, plywood manufacture, instruments | Dermatitis (wood cutters’ disease) due to lichens growing on the bark of beech trees, rhinitis, asthma, nasal cancer |
| Birch (paper, white) | US and Canada (paper birch) Europe (white birch) |
Furniture, decorative objects, pulp and paper | Irritant dermatitis |
| Cedar, Western Red | West Coast of North America | Building construction material, boats, planking, framing | Asthma, allergic contact dermatitis, sensitizer, decrease in lung function, eye irritation and conjunctivitis, rhinitis |
| Douglas Fir | West coast of North America, Europe |
Interior and exterior construction, flooring, boats, veneer, furniture | Contact eczema, decrease in lung capacity |
| Fir (grand, balsam, silver, alpine) |
US and Canada Europe (silver fir) |
Interior construction, joiner, plywood | Skin irritation, dermatitis, rhinitis, asthma, possible decrease in lung function |
| Hemlock | North America | Furniture, cabinetry | Skin irritation, decreased lung function |
| Larch | Europe, North America | Construction, frame work, boats, flooring | Allergic dermatitis from European larch, no reports with western larch |
| Mahogany | Africa | Furniture, cabinetry, boats, mouldings, etc.- all purpose wood, used where good quality wood is required | Dermatitis, sensitizer |
| Maple | Europe, North America | Furniture, interior construction, cabinets | Rhinitis, asthma, Maple Bark Strippers’ Disease (mould spores in bark) |
| Oak | Europe, North America | Furniture, decorative veneer | Nasal cancer |
| Pine (white, lodgepole, jack) |
Europe, North America | Interior and exterior construction, pulp and paper |
Skin irritation, contact dermatitis, Wood-Pulp Workers’ Disease (mould in bark), rhinitis, and asthma |
| Poplar | Europe, North America | Plywood, matches, toys, pulp and paper | Contact dermatitis (with sawdust contact), rhinitis |
| Rosewood | South America, Asia | Decorative veneer, furniture, cabinets instruments | Eczema, allergic contact dermatitis |
| Spruce | Europe, North America | Interior and exterior construction, furniture, pulp and paper | Skin irritation, Wood-Pulp Workers’ Disease (mould spores in bark), decrease in lung function |
| Teak | Asia, Africa, West Indies | Ship building, interior fittings and mouldings, furniture, flooring |
Toxic, dermatitis, sensitizer |
| Walnut (black) | Europe, US | Veneer, cabinet making, furniture, decorative paneling, gun stocks | Skin irritation, rhinitis, possible asthma |
| Yew | Europe, Asia, North Africa | Carving, veneer, cabinet making | Irritation of skin, dermatitis, toxic |
