All wool can be washed in a machine and tumble dried but it has to be gentle and cold wash cycle with mild detergents, and low heat drying. Hot water and hot drying will destroy wool. Strong detergents or over-saturation in detergent will also harm wool and often make it smell funny and itch your skin as the detergent doesn't get rinsed properly. It's best to put them in net-bags to avoid stretching in wash. I wash my stuff once a week at a laundromat.

Adam