The use of the Extended Hata model for indoor-outdoor propagation introduces the following additional terms.
Median path loss
(Eq. 206)
where Lew is the attenuation due to external walls. In the case the Rx is indoor then the Lew is the wall loss defined at the Rx and when the Tx is indoor the wall loss defined at the Tx is considered.
Variation in path loss
Uncertainty on materials and relative location in the building increases the standard deviation of the log-normal distribution :
comment from word file: subindex of sigma on the LHS was changed from indoor-indoor to indoor-outdoor
(correct EQ to be inserted)
(Eq. 207)
when the Rx is indoor and Tx outdoor or
comment from word file: subindex of sigma on the LHS was changed from indoor-indoor to indoor-outdoor
(correct EQ to be inserted)
(Eq. 208)
when the Tx is indoor and Rx outdoor where 
and 
are the wall loss standard deviation defined at the Rx and Tx respectively.