Abstract: A degradation device for degrading tires includes an enclosed chamber (3) providing an annular housing space for a tire (1) to be treated. A microwave generator is connected to a wave guide (18) for splitting the generated microwave energy into arms (20 and 19) which are provided with outlets which will direct the energy both externally and internally of the annulus of the housing space. The microwave energy will cause the tire to break down into constituent parts. The chamber (3) is reciprocated and rotated with respect to the tire so that the microwaves will be projected relatively evenly through the tire. An inert gas is introduced into the chamber at (29), to limit the possibility of combustion or oxidation of degradation products created by the process. Volatile gaseous products of the process are drawn off through the exhaust pipe (26). Solid degradation products are created and are removed at the end of the process.