Source: https://jmrplens.github.io/phonometry/guides/sections/vibration/ Vibration matters to acoustics twice. First as a **source of sound**: a pump or fan bolted to a building injects structure-borne power that travels through walls and floors and re-radiates as audible noise rooms away. Second as a **human exposure** in its own right: vibration transmitted to a standing, seated or hand-gripping person is measured, weighted and limited much like noise, with its own metrics and legal action values. The **structure-borne sources** pages follow the source chain in order. The frequency-response-function family of ISO 7626 (receptance, mobility, accelerance) is the vocabulary; the transfer stiffness of ISO 10846 characterises the resilient elements that interrupt the path; ISO/TS 7849 estimates the airborne power a vibrating surface radiates directly; EN 15657 measures the structure-borne power a machine injects into a reception plate; and EN 12354-5 assembles all of it into the sound pressure level predicted in a receiving room. That final prediction is also where this section hands over to the [sound insulation](/phonometry/guides/sections/sound-insulation/) models of the buildings section. The **human vibration** pages share the measurement philosophy of a sound level meter, applied to acceleration: frequency weightings that reflect body response, running and integrated averages, and dose quantities compared against the action and limit values of Directive 2002/44/EC, plus the dedicated spinal-response model for vibration containing repeated shocks. Start with [Mechanical mobility and the FRF family](/phonometry/guides/mechanical-mobility/) if you care about machines and buildings, or with [Human Vibration](/phonometry/guides/human-vibration/) if you care about people. ## [Structure-borne sources](/phonometry/guides/sections/structure-borne/) From FRF vocabulary to the predicted level in a receiving room. - [Mechanical mobility and the FRF family (ISO 7626-1)](/phonometry/guides/mechanical-mobility/): receptance, mobility and accelerance with their reciprocals, and the SDOF reference resonator. - [Bending-wave transmission at plate junctions (Cremer/Craik/Hopkins)](/phonometry/guides/junction-transmission/): the frequency-independent wave-approach coefficients for rigid X, T, L and in-line junctions, their angular average and the derived coupling loss factor and Kij. - [Transfer stiffness of resilient elements (ISO 10846)](/phonometry/guides/transfer-stiffness/): the dynamic transfer stiffness of vibration isolators by the direct and indirect methods. - [Sound power from surface vibration (ISO/TS 7849)](/phonometry/guides/vibration-sound-power/): radiated airborne power from surface velocity and a radiation factor. - [Structure-borne sound power of equipment (EN 15657)](/phonometry/guides/structure-borne-power/): the reception-plate method and the plate-independent source quantities. - [Installed structure-borne sound (EN 12354-5)](/phonometry/guides/installed-structure-borne/): the receiving-room sound pressure level predicted from source and receiver mobilities. ## [Human vibration](/phonometry/guides/sections/human-vibration/) Vibration transmitted to the human body, from daily exposure to spinal injury risk. - [Human Vibration](/phonometry/guides/human-vibration/): whole-body and hand-arm weightings (ISO 8041-1), r.m.s. and dose measures (ISO 2631-1), daily exposure A(8) (ISO 5349) and the Directive 2002/44/EC values. - [Multiple-shock whole-body vibration (ISO 2631-5)](/phonometry/guides/multiple-shock-vibration/): the spinal-response model and the probability of lumbar injury for vibration containing multiple shocks.