FILM BADGE & TLD DOSIMETRY Dr.Sayed abbas NMT 232 Lecture 3

1. FILM BADGE & TLD DOSIMETRY Dr.Sayedabbas NMT 232 Lecture 3

2. As a result of the exposure of workers to ionizing radiation has to be a way to measure and quantify these radiations. • Should this method relies on personal radiation protection. • Examples of such tools are: • FILM BADGE & TLD DOSIMETRY

3. 1- FILM BADGE • When ionizing radiation falling on the surface of the film interact with delicate silver atoms scattered through the gelatinous material constituents of the film. • Given the interaction of ionizing radiation with film material indirect effect even chemically treated inside the dark room. • Vary the sensitivity of films depending on the type of ionizing radiation.

4. FILM BADGE 1- Made of plastic material2- Covered from one side or from the sides with a thin layer of gelatin.3- Supported by silver nitrate.4- Segments of the film dimensions ranging from 3 x 4 cm covered with tightly to prevent light leakage.

5. Al Pb/Sn Cd/Pb Al Cd/Pb Pb/Sn

6. Performing functions of the metal strips 1- Lead slice:Stop the alpha and beta particles and gamma rays ranging receives its power from 60 kev and more.2- Cadmium slice:Help on the interaction of neutrons with cadmium and produces about the interaction of gamma rays.

7. 3- Aluminum slice:Reduce the sensitivity gamma-ray film and X-rays with a capacity of less than 60 kev, it stopped the film sensitivity to alpha and beta particles. 4- Window film:Used in the calculation of the radiation exposure to doses of alpha and beta particles.

8. Chemical treatment of films • After exposing the film to ionizing radiation, ionizing radiation effect within the installation of the sensitive film. • This effect does not appear before the treatment of chemically films within a dark room there is inside a red bulb. • Are removed cartoonish cover and black casing surrounded slide film.

9. Films are immersed in the liquid basin for a period ranging between 3 - 5 minutes liquid known as appearance. • The film is rinsed with water. • Then dipped again in another liquid basin for 3 - 10 minutes and liquid known as the installer. • And then re-rinse again with water. • After chemical treatment appear in ordinary light degree of blackness within the film material similar with the severity of ionizing radiation falling on them. • Degree of blackness is measured using a photocell

11. Densitometer

12. 2- TLD

13. When these materials exposed to radiation gaining electrons enough energy to rise from the valence to the conductive region. • Captured some of the electrons belonging to the parity in the area of fisheries exist in the region, the tanker.

14. These electrons remain captive in fisheries that receive external power (typically by heating thermal) is sufficient to edit. • When the liberated electrons return to the valence region lose its capacity by issuing a claims the photon photosynthesis. • Be the amount of optical photons emitted during the heating process commensurate with the amount of radiation suffered by the article before you start heating.

15. 17 mg/cm 2 (open window) 242 mg / cm 2 ABS plastic + 91 mg/cm 2 copper 600 mg/cm 2 ABS plastic