This part of ISO 10140 specifies laboratory methods for measuring the impact sound insulation of floor assemblies. The test results can be used to compare the sound insulation properties of building elements, classify elements according to their sound insulation capabilities, help design building products which require certain acoustic properties and estimate the in situ performance in complete buildings. The measurements are performed in laboratory test facilities in which sound transmission via flanking paths is suppressed. The results of measurements made in accordance with this part of ISO 10140 are not applicable directly to the field situation without accounting for other factors affecting sound insulation, such as flanking transmission, boundary conditions, and loss factor. A test method is specified that uses the standard tapping machine (see ISO 10140-5:2010, Annex E) to simulate impact sources like human footsteps when a person is wearing shoes. This part of ISO 10140 is applicable to all types of floors (whether heavyweight or lightweight) with all types of floor coverings. The test method applies only to laboratory measurements. NOTE When the aim of impact sound insulation measurements is to have a strong correlation between a “real” impact source (e.g. a person walking or children jumping) and an artificial impact source (e.g. a tapping machine), it is intended that both sources apply the same input force spectrum to ensure the correct ranking of floors and floor coverings for the “real” and the artificial source, and it is intended that the impedance spectra of the sources be the same. If the “real” impact source is a walking person without shoes and the artificial source is a standard tapping machine such as that specified in Clause 4, the correlation is not strong. An alternative method, using a heavy/soft impact source for assessing the impact sound insulation of a floor against impact sources with strong low-frequency components, such as human footsteps (bare feet) or children jumping, is given in Annex A. Alternative impact sources (i.e. a proposed modification of the standard tapping machine to make its dynamic source characteristics similar to those of a person walking barefoot and a heavy/soft impact source with dynamic source characteristics similar to those of children jumping) are defined in ISO 10140-5:2010, Annex F. A method to test floor coverings is described in ISO 10140-1:2010, Annex H, for single- or multi-layer floor coverings installed on specific reference floors. In the case of multi-layer coverings, they can be factory-assembled or assembled at the test site.