ISO 7626-1:2011 defines basic terms and specifies the calibration tests, environmental tests and physical measurements necessary to determine the suitability of impedance heads, force transducers and motion response transducers for use in measuring mechanical mobility. Primarily, it provides guidelines for the selection, calibration and evaluation of the transducers and instruments for their suitability in making mobility measurements. Procedures for carrying out mobility measurements in various circumstances are dealt with in subsequent parts of ISO 7626.ISO 7626-1:2011 is limited to information which is basic to various types of driving-point and transfer mobility, accelerance and dynamic compliance measurements. Measurements of the blocked impedance are not dealt with.