ISO 140-11:2005 specifies methods for measuring the acoustic properties of floor coverings from the viewpoint of reducing impact sound transmission. The purpose of ISO 140-11:2005 is to establish a method for determining the impact sound insulation of a floor covering under standard test conditions. The test is limited to the specification of procedures for the physical measurement of sound originating from an artificial impact source (tapping machine) under laboratory conditions and is not directly related to the subjective significance of the results. In ISO 140-11:2005, a test method is described using the standard tapping machine to simulate impact sources like human footsteps with shoes. In addition, methods using a modified tapping machine and a heavy/soft impact source are also introduced in informative Annexes C and E for the assessment of impact sound insulation of a floor covering against impact sources with strong components at low frequencies, such as human footsteps or children jumping. As a simplified method for the measurement of the reduction of floor impact sound pressure level by soft and resilient floor coverings, the method using a wooden mock-up floor is introduced in Annex D. ISO 140-11:2005 is applicable to all floor coverings, whether single or multi-layered, as installed on lightweight floors. In the case of multi-layered coverings, they can be factory-assembled or assembled at the test site. The test method is applicable only to laboratory measurements. It does not contain any provision that permits an assessment of the effectiveness of a floor covering in situ.