To provide a cap of a device for processing waste gas and of equipment for processing waste gas which are properly and separately disposable in accordance with the recycle law after waste gas processing as they are.

On the back face of a thin top panel, a passage for releasing gas is provided. On the outer edge of the panel, a plurality of strips are formed in a hanging manner. The strips are formed with fitting protrusions in such a way that the protrusions face each other. The distance between the facing protrusions is smaller than the outer diameter of the valve mountain valve seat. The bottom ends of the protrusions are formed with a slide corner, and the distance between the slide corner and the outer end of the slide corner is bigger than the outer diameter of the valve seat. The strips are provided with elasticity comprehensively.