IEEE C95.1 (radio frequency) and C95.6 (low frequency) standards for human protection from electromagnetic fields are being under revision. In the next revision, they will be combined into one standard. Even though C95.1 standard considers anatomical human models for deriving the relationship between internal and external field strengths, ellipse is used in C95.6 (low frequency) standard. It is worth computing their relationship and associated technical issues when using anatomical models. In this study, two different codes developed at Nagoya Institute of Technology and Aalto University were used for inter-comparison. Computational results suggested that the relationship between in-situ and external field strengths are in good agreement when considering 99th percentile of in-situ electric field; less than 10%. The classification of body parts is one of the essential factors for determining the in-situ field strength in 'the limb' and 'other tissues'.