Abstract. The Fusion Advanced Study Torus (FAST) has been proposed as a possible European satellite facility to study in deuterium plasmas fast ion physics in conditions relevant to a burning plasma. Energetic 3 He particles, with dimensionless parameters close to those of the fusion-born alphas in ITER, can be produced in FAST via 30 MW power ICRH minority heating. This work provides a first assessment of the extent to which the 3 He fast ion population can be diagnosed in FAST with a set of dedicated confined fast particle diagnostics. Neutron Emission Spectroscopy (NES), Gamma-Ray Spectroscopy (GRS) and Collective Thomson Scattering (CTS) diagnostics have been reviewed with a description of the state-of-the-art hardware and a preliminary analysis of the required lines of sight. The results of the analysis, based on numerical simulations of the spatial and energetic particle distribution function of the ICRH-accelerated ions for the standard FAST H-mode scenario, suggest that NES and GRS measurements can provide an information on the anisotropy of the fast 3 He population and a l measurement of its effective tail temperature, with time resolutions in the range 20-100 ms. The proposed CTS diagnostic can measure the fast ion parallel and perpendicular temperature with a spatial resolution of 5-10 cm and a time resolution of 10 ms. The paper provide a scientific basis for the predictions of FAST capability in the production and diagnosis of energetic ions.