Post-irradiation tritium release from the Pebble Bed Assembly (PBA) neutron-irradiated beryllium (Be) pebbles (empty_set approximately 1 mm; the total tritium inventory 2-4 GBq/g) was investigated on annealing in He + 0.1% H2. Temperature ramps of 2.3 K/min followed by annealing for 1 h at 1310-1320 K resulted in complete detritiation of the PBA Be pebbles. The tritium burst release occurred after a time lag of 1-6.5 h during constant temperature anneals at 1089-1180 K, with the release time measured after reaching the annealing temperature. Tritium burst release was also observed to occur during cool down. Anneals at 1089 K for 8 h and at 1045 K for 23 h caused detritiation of the PBA Be pebbles by >=75%. Effective values of the tritium diffusivity were estimated for the PBA Be pebbles as 2.6 10-13 m2/s for 1045 K; 4.7-5.1 10-13 m2/s for 1089 K.