Vessels and parts subject to pressure whose rupture could create unacceptable risk are designed so that loss of pressure or vacuum and fluid jets from leakage or component failure cause no unacceptable risk, vulnerable pipes and hoses are protected against external effects, reservoirs and accumulators lose their pressure automatically once the equipment is cut off from its supply or else have isolation or local depressurising means with pressure indication, and elements that stay pressurised after isolation carry plainly marked exhaust devices and a warning that pressure must be released before adjustment or maintenance. The maximum pressure a part can see in normal and single fault condition is the highest of the rated maximum external supply pressure, the setting of a relief device in the assembly, and the maximum a source in the assembly can develop unless relief-limited, and it does not exceed the part's maximum permissible working pressure except as relief devices allow. A pressure vessel above 50 kPa whose pressure times volume exceeds 200 kPa litres withstands a hydraulic test at the working pressure times the Figure 32 factor, raised gradually and held for one minute, without bursting, permanent deformation or leakage (gasket leakage tolerated only above 40 percent of the test value or the working pressure, none for toxic, flammable or hazardous contents), with pneumatic or other suitable tests where hydraulic testing is impossible. Where a relief device is required, the pressure-control device regulating pressure works through 100,000 cycles at rated load and keeps pressure below 90 percent of the relief setting in any normal use; and relief devices are fitted at every point where the maximum permissible working pressure might otherwise be exceeded, connected as close as practical to the protected part, accessible for inspection and maintenance, not adjustable or defeatable without a tool, discharging away from persons and from parts where deposits would be risky, of capacity to hold pressure within 10 percent above the working pressure on failure of supply control, with no shut-off valve between device and protected parts, and rated for 100,000 cycles except one-time devices such as bursting discs. Support-system pneumatic and hydraulic parts additionally meet 9.8.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.