Presently Personnel Monitoring against external radiation is being carried out using CaSO₄: Dy phosphor based TLD badge and hot N₂ gas based semiautomatic TLD Badge Reader (TLDBR-7B). This System requires the supply of high purity N₂ gas for the operation of the reader. This gas is normally obtained from N₂ gas cylinders use of which is a cumbersome, tedious, cost intensive and involves safety hazards. To minimize the dependence on conventional gas cylinders, a medium sized plant for generation of N₂ gas directly from air has been installed and coupled to gas station and distribution system. The paper describes the comparative study of performance of TLD reading system using gas from the generator with that using gas cylinders, which has been found to be quite comparable. This upgradation has helped in drastic reduction in cost, labour and improved safety in TLD Laboratory working.