One cannot overstate the value and ever growing importance of the screw conveyor and one cannot overemphasize the intrinsic danger associated with this classic monster. This danger can be controlled using fixed enclosure guards that are not only compatible with the function of screw conveyors but are anecdotally acknowledged to be the most desirable type of guard. Nevertheless, the speciality conveyor standards promulgate dangerous guarding systems with features two levels below the fixed barrier guard. This paper revisits the system of conveyor safety standards to rout out equivocal notions, expose shortcomings, and generally demonstrate that a foolish inconsistency is not the hobgoblin of small minds. Finally, this paper challenges the notion that a fixed enclosure guard is an elementary concept whose parameters are settled; e.g. a machine inside of a welded steel box. The definition of fixity and the duality of operation and maintenance are both explored.
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