Here is the relevant part from ANSI/HI 6.6-1994 Reciprocating Pump tests. This is what we use. We don't have B31.1, seems not applicable, title is Power Piping. The BS is unknown to me.
6.6.5 Hydrostatic test of pressure-retaining components
6.6.5.1 Objective
To demonstrate that the pump when subjected to liquid pressure will not leak or fail structurally.
For the purpose of this requirement, "will not leak" means only prevention of escape of liquid through the external surfaces of the pump, normally to atmosphere (see Paragraph 6.6.8.3).
6.6.5.2 Test parameters
Each part of the pump that contains liquid under pressure shall be capable of withstanding a hydrostatic test at not less than 150% of the pressure that would occur in that part when the pump is operating at rated conditions for the given application of the pump.
Components or assembled pumps — The test shall be conducted on either the liquid-containing components or the assembled pump.
Components — The test shall be conducted on the liquid-containing components such as pump cylinders. Care must be taken not to impose pressure in excess of 150% of design on areas designed for lower pressure operation.
Assembled pump — The test shall be conducted on the entire liquid-containing area of the pump, but care must be taken not to impose pressure in excess of 150% of design on areas such as inlet manifolds.
Test duration — Test pressure shall be main-tained for a sufficiënt period of time to permit complete examination of the parts under pressure. The hydrostatic test shall be considered satisfactory when no leaks or structural failures are observed for a minimum of 3 minutes for pumps 100 horsepower (75 kW) and below, 10 minutes above 100 horsepower (75 kW).
Test liquid — Test liquid shall be water or oil having a maximum viscosity of 150 SSU (32 cen-tistokes) at test temperature.
Temperature — If the part tested is to operate at a temperature at which the strength of material is below the strength of the material at room temperature, the hydrostatic test pressure should be multiplied by a factor obtained by dividing the allowable working stress for the material at room temperature by that at operating temperature. The pressure thus obtained will then be the minimum pressure at which hydrostatic pressure should be performed. The data sheet should list the actual hydrostatic test pressure.
6.6.5.3 Test procedure
Components to be tested shall have all the openings adequately sealed. Provisions must be made to vent all the air at the highest point on the component. The item shall be filled with the test liquid, pressurized, and the test pressure shall be maintained for the duration of the test. No leakage
through the component tested shall be visible; however, leakage through the stuffing box packing or between valves and seat shall be permitted.
6.6.5.4 Records
Complete written or computer records shall be kept of all pertinent information and retained on file, available to the user by the test facility for two years. This information should include:
1) Identification by models, sizes, serial number;
2) Test liquid;
3) Maximum allowable pressures and temperature;
4) Hydrostatic test pressure and test durations.