AVANTTEC TLD Gebrauchsanweisung - Seite 3

Blättern Sie online oder laden Sie pdf Gebrauchsanweisung für Messgeräte AVANTTEC TLD herunter. AVANTTEC TLD 11 Seiten. Personnel monitoring service

Avanttec Laboratories (P) Ltd

1) GENERAL FEATURES OF TLD BADGES

a. It is used to measure external individual doses from X, beta and gamma radiations. It consists of a TLD card

loaded in a cassette having suitable metallic filters. It is based on the phenomenon of thermo luminescence, the

emission of light when certain materials are heated after exposure to radiation. It gives very reliable results since

no fading is observed under extreme climatic conditions (ambient temperature and humidity).

b. TLD card: A TLD card essentially consists of three CaSO4: Dy-Teflon TLD discs (13.3mm dia x 0.8 mm thick)

mechanically clipped over three symmetrical circular holes each of diameter 12 mm, on a nickel plated aluminum

plate (52.5mmx29.9mmx1mm). An asymmetric V cut provided at one end of the card ensures a fixed orientation of

card in the TLD cassette. A thin paper wrapper (12mg/cm2) provides personal data & the period of use. To protect

the TLD discs from dust and mishandling, the card along with its wrapper is sealed in a thin plastic (polythene)

pouch. Pouch also protects the card from radioactive contamination while working with open sources.

c. TLD Cassette: TLD cassette (card holder) is made of high impact plastic. TLD card when inserted in the proper

position in the cassette will have the first disc (D1) sandwiched between a pair of filter combination of 1 mm A1 &

0.9 mm Cu (1000 mg/cm2 , total thickness). Copper filter is nearer to the TLD disc. The second disc (D2) is

sandwiched between a pair of 1.5 mm thick plastic filters (180 mg/cm2). The third disc (D3) is positioned under a

circular open window. A clip or strap attachment affixes the badge to the user's clothing or to the wrist.

TLD CARD USERS INSTRUCTION MANUAL Rev.E-5.01 – 11.07.19