Bulk cement bins, containers and silos need conical or tapered bottoms and a mechanical or pneumatic means to start material flow; nobody may enter a storage facility until the ejection system is shut down, locked out and tagged against operation. Concrete mixers with loading skips of one cubic yard or more need a mechanical means of clearing material from the skip, plus guardrails on each side of it. Manually guided powered rotating concrete trowels need a switch that cuts power automatically when the operator's hands leave the handles. Concrete buggy handles may not stick out beyond the wheels on either side. Concrete pumping systems with discharge pipes need pipe supports designed to take a 100 percent overload, and compressed air hoses on pumping systems need positive fail-safe joint connectors so sections cannot separate under pressure. Concrete buckets with hydraulic or pneumatic gates need positive safety latches or similar devices against premature or accidental dumping, and buckets must be designed so concrete does not hang up on the top and sides. Tremie sections and similar conveyances must be tied together with wire rope or an equivalent in addition to their normal couplings. Bull float handles that could touch energized conductors must be nonconductive or insulated with a sheath giving equivalent protection. Masonry saws need a semicircular blade enclosure that incorporates a way to retain blade fragments. No maintenance or repair may be done on concrete and masonry equipment (for example mixers, pumps, screens or compressors) where unexpected operation could injure someone unless every hazardous energy source is locked out and tagged, with tags reading Do Not Start or similar.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.