This part of IS0 9854 specifies the general test method to be used for the determination of the impact strength of unnotched test pieces cut from thermosplastics pipes for the transport of fluids. It is not intended to be a reference test method for the determination of the impact strength of pipes. IS0 3127, relating to the determination of the impact strength of pipes by means of a falling mass, is the reference method. However, this part of IS0 9854 may be used for scientific research, materials testing or the examination of pipes when it is not possible to take measurements in accordance with the reference method. This part of IS0 9854 may be applied to either isolated batches or continuous production of pipe, and the test may be carried out at - 20 “C, 0 “C or 23 “C, depending on the pipe material and/or size. For the test parameters, i.e. impact energy, test piece dimensions, shape and spacing of the test piece supports and type of test piece, to be used to determine the pendulum impact strength of pipes, the specifications for specific materials are given in IS0 9854-2, as appropriate.