Ultraviolet (UV) dosimetry

An apparatus comprising:

• a vessel having a vessel wall, the vessel wall being at least partially transparent to visible light, the vessel wall further being at least partially transparent to ultraviolet (UV) radiation;
• a membrane secured to the vessel, the membrane being permeable to oxygen, the membrane being impermeable to water, the membrane for preventing water ingress to the vessel;
• and
• a dosimeter located within the vessel, the dosimeter for detecting a dosage of the UV radiation, the dosimeter being reusable, the dosimeter comprising:
• a substrate;
• a UV-sensitive layer accessible to the UV radiation, the UV-sensitive layer being located on the substrate, the UV-sensitive layer comprising:
• a first concentration of semiconductor material having a band gap, the band gap corresponding to photon energy of the UV radiation, the semiconductor material being homogeneously distributed in the UV-sensitive layer, the first concentration being between approximately 0.0001% and approximately 5% by weight of the UV-sensitive layer, the semiconductor material being one selected from the group consisting of:
• titanium dioxide particles;
• zinc oxide particles;
• and
• tin oxide particles;
• a second concentration of a UV-oxidizable dye, the UV-oxidizable dye having an oxidation state and a reduction state, the UV-oxidizable dye having a first color in the oxidation state, the UV-oxidizable dye having a second color in the reduction state, the first color being distinguishable from the second color, the UV-oxidizable dye being homogeneously distributed in the UV-sensitive layer, the second concentration being between approximately 0.001% and approximately 0.1% by weight of the UV-sensitive layer;
• a third concentration of an irreversibly oxidizable sacrificial electron donor, the irreversibly oxidizable sacrificial electron donor being homogeneously distributed in the UV-sensitive layer, the irreversibly oxidizable sacrificial electron donor for oxidation when exposed to the UV radiation, the third concentration being between approximately 10% and approximately 50% by weight of the UV-sensitive layer, the irreversibly oxidizable sacrificial electron donor being one selected from the group consisting of:
• a cellulose;
• glycerol;
• hydroxyethyl cellulose;
• ethyl cellulose;
• sodium iodide;
• an inorganic reducing agent;
• triethanolamine;
• and
• ascorbic acid;
• a fourth concentration of a polymeric matrix material, the polymeric matrix material being homogeneously distributed in the UV-sensitive layer, the fourth concentration being between approximately 1% and approximately 50% by weight of the UV-sensitive layer;
• and
• a barrier for protecting the UV-sensitive layer, the barrier being located on the UV-sensitive layer, the barrier being permeable to oxygen, the barrier being impermeable to water.