The potential of low-cost portable electronic devices for emergency dosimetry

For a long time, smartphones have been explored as potential emergency dosimeters using the Optically Stimulated Luminescence (OSL) method with resistor substrates, but the destructive nature of this approach may deter widespread acceptance. In contrast, less valuable devices such as key fobs, earbuds, E-cigarettes, and GPS tags offer a compelling solution, despite having fewer resistors, which could limit dose reconstruction using the conventional OSL. The Red Thermoluminescence (RTL) method, however, offers an alternative by using enhanced signals in the red wavelength range. Our study investigates the potential of low-cost electronics for dosimetry through an innovative RTL approach. RTL measurements of resistors extracted from gadgets of everyday use underscore the necessity of optimisation of the TL peak integration range when preheating is omitted. We identified crucial parameters: the influence of an unstable 80 °C peak up to 150 °C and an intrinsic background signal that established the upper integration limit at 180 °C. Intrinsic background dose was (5.6 ± 4.5) mGy. The RTL signals demonstrated linear dose responses up to 10 Gy, with negligible sensitivity variation (<3%). This enabled an accurate dose measurement immediately after 1 Gy irradiation. However, variability in fading rates of different items introduced significant uncertainty in dose reconstruction. Validation via gamma-irradiation trials confirmed the feasibility of dose reconstruction with ∼16% (1σ) precision up to seven days post-irradiation. The RTL positions low-cost personal electronics as viable tools for emergency dosimetry, particularly when high sensitivity is required due to limited sample availability.