## 2 Transmissibility of the Acceleration Base
Based on the interpretation of Figure 1, the following can be concluded: a lot of research does not take into account the fact that, at high vibration frequencies (>250 Hz), the finger and the hand are subject to conditions for the appearance of symptoms of occupational hand diseases, which have direct links to the methodological weighting norms imposed by SR EN ISO 5349/2003. According to [29], the hand component related to the coupling force in the operation of a vibrating tool is generally made up of the applied force (AF) and the biodynamic force (BF). There is wide interest in quantifying the coupling force. The objectives of this study are to develop an effective method for estimating the BF and investigate its fundamental characteristics. Using the biodynamic response of the hand-arm system, such as the apparent mass or mechanical impedance and the acceleration which can be measured on vibrating tools, this study proposes an indirect method for BF estimation. The distribution of BF on the fingers and the palm and along the forearm, using the z\({}_{\text{h}}\)-axis, is analyzed when operating eighteen types of tools. The results indicate that the BFs depend on both the tool vibration spectrum and the biodynamic properties of the hand-arm system [29]. The dominant BF frequency component is usually at the same frequency as the dominant vibration frequency of each tool. The BF distributed on the palm (2-98 N) is much higher than that distributed along the fingers (1-30 N) at frequencies less than 100 Hz, but these biodynamic forces (2-22 N) are comparable at higher frequencies. The distribution of BF by the palm on several tools has relatively low dominant frequencies (\(\leq\)40 Hz), in particular in the resonant frequency range (16-40 Hz), and is comparable with the palm force applied by 50-100 N. \begin{table}
\begin{tabular}{c c c c c c c c} \hline
**Anatomical Location and** & **Unweighted** & **SR EN ISO** & **Digit or** & **Dorsal** & & & \\
**SR EN** & **Value** & **5349/2003** & **Finger** & **Palm** & & & \\ \hline SR EN ISO 5349/2003 & 0.459 & - & - & - & - & - & - \\ Finger & 0.948 & 0.523 & - & - & - & - & - \\ Dorsal Palm & 0.946 & 0.613 & 0.986 & - & - & - & - \\ Wrist & 0.407 & 0.997 & 0.482 & 0.569 & - & - & - \\ Elbow & 0.185 & 0.936 & 0.241 & 0.341 & 0.947 & - & - \\ Shoulder & 0.278 & 0.932 & 0.320 & 0.422 & 0.932 & 0.984 & - \\ Head & 0.033 & 0.801 & 0.013 & 0.095 & 0.817 & 0.955 & 0.937 \\ \hline \end{tabular}
\end{table} 
Table 1: Correlation coefficients obtained for each pair of measured a\({}_{\text{RMS}}\) acceleration values and TAB values, in the anatomical locations of the finger-hand–arm system in comparison with SR EN ISO 5349/2003, in conformity with [1]. In conformity with [30], symptoms of occupational hand diseases (such as white finger syndrome and diseases of the peripheral nervous system) appear due to prolonged and intensive exposure to vibrations from orbital and grinding equipment. These can cause finger diseases, which could be associated with the biodynamic responses of these appendages. The biodynamic responses of the hand-arm system have also been studied by many researchers, but the detailed biodynamic responses distributed between the substructures (phalanges) of the hand have not been sufficiently studied [30]. To advance knowledge in this aspect and help develop improved finite-element models of substructures, the study cited above used ten subjects (five men and five women) who participated in the experiment, simultaneously measuring their biodynamic response to the input of the vibrating system, related to the transmissibility of vibrations to the fingers and palms exposed to vibration. Vibrations from the studied flat disk also allowed the researchers to examine the relationship between these two measures rendered by biodynamic responses. A scanning laser vibrometer can be used to measure vibrations' distribution. The above study confirmed that hand responses to distributed vibrations (like acceleration R.M.S.)