A strain gauge includes a substrate for mounting an element to be reversibly lengthened by a force applied while displaying a variation in the resistance thereof, the element lengthening itself along an axis for measurement by the gauge. In one technique, content is \u201ctagged\u201d with a service-associated icon and a keyword. The theater seat assembly may also include a molded cover attached to at least one of the seat frame and the back frame and being injection molded from a fiberglass reinforced co-polymer. An oxygen-containing gas is fed to the reaction space, in order to affect the combustion of the waste and produce gases and solid material.