A probehead for an electron spin resonance (ESR) dosimeter, comprising a resonator, an insert extending into said resonator and having a guide channel for bringing a sample into said resonator, said sample comprising a dosimeter substance, and a pressurized air unit for blowing said sample out of said resonator after completion of a measurement, wherein said insert has an opening on an upper side of said resonator, said opening being openly accessible for manually inserting dosimeter pills thereinto, said insert, further, being provided on said upper side with a pressurized air connector, said pressurized air connector being connected to an orifice via a pressurized air channel within said insert, said orifice being located within a lower, otherwise closed bottom of said guide channel.