The wall conditioning of the ADITYA tokamak is usually done, by first producing an electron cyclotron resonance (ECR) plasma inside the vessel and then superimposing a pulsed ohmic discharge on the ECR background. Sometimes, helium gas is used as a working gas. In this article, the spectral line emissions of neutral helium for the two different plasmas - namely, the ECR and the pulsed discharge cleaning (PDC) plasmas - have been analyzed using a collisional-radiative (CR)-model code to estimate the electron density and temperature. We are able to match the experimentally obtained relative intensity ratios with those predicted by the model under the assumption of ionizing plasma condition if the possible effects of the metastable states are not ignored. This has been done by using the populations of two metastable levels (2 1S and 2 3S) as independent parameters in addition to the ground states of neutrals and ions in the CR model under a quasisteady-state approximation. It is further seen that, it is the metastables and not the recombination (including dielectronic) processes that lead to a better fit with experimental observations. The column density of neutrals inferred from this analysis implies that the emission from the PDC discharge emanates from a large region of the vessel, while in the ECR discharge, the plasma responsible for the emission is restricted to a narrow region. This is also borne out by experimental observation. © 2005 American Institute of Physics.