This International Standard specifies a laboratory performance test method for power assembly tools for installing threaded fasteners. It gives instructions on what to test for and how to evaluate and present the test data. It is applicable to tools which apply torque continuously. It is, however, not applicable to impact wrenches, ratchet wrenches or wrenches with ratcheting clutches, or other tools which advance fasteners in discontinuous increments, overcoming static friction at each increment, in particular because the applied torque of these tools cannot be measured using conventional types of instrumentation. The test method is not intended as a routine in-plant inspection test.