The objective of this study is to examine the possibility of using the thermoluminescence (TL) of polymer fibers containing ground calcium carbonate (CaCO₃) mineral fillers as emergency dosimeters. Calcite, consisting mostly of CaCO₃, is a TL material that exhibits two distinct TL peaks that can be exploited for dosimetry and is a naturally occurring mineral that is ubiquitously in use in everyday materials. Polymer fiber materials with CaCO₃ are already produced at scale e.g. for common surgical face masks or surgical gowns, opening the possibility of using such materials as fortuitous dosimeter in emergency situations. To assess the feasibility of such materials as dosimeters, we examined the TL properties of two CaCO₃ powders as well as commercially available surgical face mask samples. The results indicate that the TL emissions across all samples stem from calcite and are in principle usable for dosimetry. We discuss limitations that arise from the fading properties and the potentially complex TL background. As a case example for emergency dosimetry, we examined samples from a commercially available surgical face mask. The face mask was found to exhibit a minimum detectable dose to the order of ∼2Gy, under laboratory conditions. We provide an outlook on how the materials and methods can be improved for radiological dose assessment.