Abstract: An improved nozzle for a gun or output means of a particle blast apparatus such as a sand blast cleaning device. The nozzle has a wear indicating lip that clearly and unambiguously shows the operator when the nozzle has reached the end of its useful life and should be replaced. The nozzle is elongated and tapered to improve power and accuracy. The nozzle has a proximal media inlet end which has a predetermined configuration which maximizes media/air mixing and flow, and minimizes turbulence and nozzle/gun interface wear. The invention also provides a method of using a particle blast apparatus, and particularly for determining when a nozzle has worn and should be replaced.

Abstract: A portable steel framed building which can be rapidly assembled and disassembled. Components of a typical building include at least one ridge beam connected between two spaced ridge receivers with two rafters also secured to the ridge receiver. The rafters extend through hip receivers each of which is connected to a hip beam and a post. Thus, two identical ridge receivers and four identical hip receivers, plus a ridge beam, two hip beams and four posts are sufficient to construct a complete building. With additional identical components, the size of the building may be extended and other configurations, such as valley, shed or gable roofs may be constructed. If desired, purlins may be provided between rafters and crosspieces may be provided between posts. Fascia members may be fastened to the ends of the rafters, and may include a component for holding the ends of a fabric roof covering. The posts may be telescoping to allow building height to be varied or irregular foundations to be accommodated.