[en] Dosemeters of the P-LiF 7-30 type (LiF built in a teflon matrix 12.7 mm in diameter and 0.4 mm in thickness) and irradiated from a ⁶⁰Co gamma source with a dose of 50 mGy were used in the experiment. The results were evaluated using the PITMAN 205 C instrument featuring fixed heating (approx. 216 degC), the PITMAN 654 ''TOLEDO'' instrument allowing to adjust any operating mode, and the developed thermoluminescent dating equipment (heating at a constant temperature of 260 degC). The following procedure was proposed and tested for the heat treatment of LiF-based thermoluminescent dosemeters: heating for 2 hours at 300 degC, cooling between metal blocks, heating for 20 hours at 80 degC and cooling between metal blocks. In the P-LiF 7-30 thermoluminescent dosemeters the procedure allows increased sensitivity and reduced fading. It is suitable for all LiF-based thermoluminescent dosemeters. (J.P.)