## 1 Introduction  
With the advent of the fifth generation (5G) of mobile wireless communication, the number of mobile subscriptions is expected to increase by 550 million [1]. The challenge for the mobile operators to contain this traffic is high as they need to design the 5G networks as optimal as possible in terms of power consumption, electromagnetic (EMF) exposure, and/or cost of deployment. The EMFexposure is required to comply with the limitations determined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) or any other organization such as the Institute of Electrical and Electronics Engineers (IEEE) and the US Federal Communications Commission (FCC), given the proliferation of the broadband wireless devices. Massive multiple input multiple output (MIMO) is expected to be utilized in the upcoming 5G cellular network to address the unprecedented high data rate requested by the users [2]. In fact, a massive MIMO 5G BS is equipped with large number of antenna elements that makes it possible to serve many users simultaneously through spatial multiplexing. Moreover, since there are many more antennas than the users, beamforming can be used to focus the signal towards the intended user without interfering with the others. These two properties have the effects of increasing both the spectral and energy efficiency of a massive MIMO 5G network [3]. Recently, the research in the area of massive MIMO has mainly focused on the minimum energy efficiency requirement during the planning process, showing a particular attention to the energy consumption of the BSs deployed within the network [4]. Since the regulations on the electromagnetic field are imposing some strict limitations on the level of BS radiated power the general public is exposed to, the network operators are required to rethink their planning process accounting for the EMF exposure constraints [5]. So far, some studies related to the design of massive MIMO (multiple input multiple output) 5G networks have only addressed the downlink (DL) EMF exposure level resulting from the transmission of the base stations (BS) towards the users. In [6; 7], the authors addressed the DL EMF exposure due to an array of 100 antennas (10 \(\times\) 10) in the context of 5G. The authors in [8] proposed a statistical approach proving that the realistic EMF compliance boundary due to the DL transmissions of a massive MIMO BS is half-reduced compared to the one obtained with the traditional method. Similarly, [9; 10] proposed a theoretical model that recommends to consider the actual maximum transmit power level for a realistic assessment of the DL EMF exposure due to a 5G massive MIMO base station, which is used by the International Electrotechnical Commission (IEC [11]). Since the BS transmit power is split over various directions depending on the locations of the users within the area of interest, the actual transmit power level of the 5G BS was found between 7-22% of the theoretical maximum power. Furthermore, in [12], the authors investigated a hybrid method combining the ray-tracing (RT) and the finite-difference time-domain (FDTD) to evaluate the DL human exposure due to a single massive MIMO base station in an industrial indoor environment. The RT served for the estimation of the propagation channels, while the FDTD was used for the simulation of the exposure of a human phantom. However, since a deployment of billions of connected objects are expected with the 5G's use case related to massive machine type communication (mMTC) [13], there is also a need to address the level of EMF exposure, resulting from the transmission the devices towards the BSs as they may have a non-negligible contribution to the global network exposure. This is denoted as uplink (UL) exposure. In this context, the works of [14; 15; 16] proposed a model of the UL exposure and investigated its contribution in the indoor or outdoor wireless network planning.