Merino wool is a natural fibre. It keeps you warm when you're cold and cool when you're hot. Merino wool can reduce the rate of heat transfer to the environment because they offer superior insulation. The surface has a waxy coating that repels liquids. Water droplets on the surface will bead and roll off instead of being absorbed into the wool. When subjected to flame, wool self- extinguishes. That is why fire fighters wear wool uniforms and natural bedding manufacturers use wool in their products to meet fire codes. Merino wool has the highest fire resistance of all commonly encountered textile fibres.