The JET deuterium-tritium experiments in 1997 (DTE1) utilised 20 grams of tritium, produced more than 2.3x1020 D-T neutrons, and generated peak fusion powers of 16MW. Significant health physics input was required to measure and quantify the radiological consequences of high yield neutron and gamma production, and of processing large tritium quantities. This paper summarises the results of radiological protection monitoring carried out during the campaign. Figures are presented of neutron and gamma doses and tritium levels in occupied areas during the D-T operations. Results are given of aerial discharges of tritium and the levels found in the local environment.