Radiation dose was measured with set of TL dosimeters during checkout of neutron radiation hardness of the ORTEC preamplifier type 142A in the experiment at the MARIA nuclear reactor at the National Centre for Nuclear Research (NCBJ), Otwock-Świerk, Poland. Different types of LiF-based TL detectors have been used for measurements in order to evaluate neutron and non-neutron components of the radiation field in the reactor channel during exposure and to check their relevancy for dose measurements in the reactor environment. For high-dose evaluation a new Ultra-High-Temperature Ratio (UHTR) method established for highly sensitive LiF:Mg,Cu,P detectors has been applied. Neutron fluence evaluated from TL measurements was in good agreement with one calculated using neutron flux data during the experiment.