**8. Dosimety audit with radiophotoluminescent dosimeters (RPLDs) in reference conditions**

The dosimetry system based on radiophotoluminescent dosimeters (RPLDs) is the Ace Dosimetry System, consisting of GD-302 M glass rods and an FDG-1000 reader from Asahi Techno Glass Corporation (ATG). It is used in IAEA Dosimetry Laboaratory (See **Figure 6**).

The glass rods are made of silver-activated phosphate glass. They are 12 mm long and 1.5 mm in diameter. Each glass rod has an identification number engraved on one end. The sensitive area of the dosimeter is 6 mm long. The glass rods are placed in specially made waterproof capsules. Each capsule with a glass rod already placed in it can be considered as an *RPLD Dosimeter* (See **Figure 7**). The capsules, model M5001 produced by MISATO Precision Inc., is made of high density polyethylene (HDPE, Nipolon Hard 2000, Tosoh Corporation, Japan). It consists of a container with approximate cylindrical symmetry and with an internal 12.1-mm-long cylindrical cavity of 1.8 mm of diameter [24].

The dosimetry audit with RPLDs is the newest form of the audit offering as a service by IAEA Dosimetry Laboratory to the Member States. The participants

#### **Figure 6.**

*Dose Ace dosimetry system consisting of GD-302 M glass rods and an FGD-1000 reader/analyzer from the Japanese Asahi Techno Glass Corporation (ATG).*

**Figure 7.** *Glass rods on the left and waterproof capsule on the right.*

### *Radiation Oncology*

(radiotherapy centers) should to irradiate the RPLDs in a water phantom using an IAEA standard holder in reference conditions: S = 10x10 cm field size, 10 cm depth in water phantom and nominal Source Surface Distance (SSD) or Source Axis Distance (SAD) of 100 cm used clinically.

Each capsule has an ID number and a bar code. The sensitive area is also marked on the capsule to allow precise positioning (See **Figure 8**).

The purpose of the dosimetric audit is to perform the measurements specified in the instruction in the same conditions under which the patients are irradiated on daily basis (See **Figure 9**).

The irradiation procedure of RPLDs includes the following steps according to the IAEA instruction sheet [25, 26]:
