Aer'ODE

A dedicated tool for Quality Assurance in Dosimetry for radiation processing

Brochure [pdf]

A flexible dosimeter analysis instrument has been developed by Aérial in order to bring a major contribution to the promotion of quality control in the field of radiation processing. This instrument is an automatic dose measurement and control system. It is PC controlled and makes it possible to obtain the dose by optical absorption dosimeters (Harwell, FWT, GEX Windose, GEX DoseStix, Risö B3, CTA, GAF chromic, PVC, ...) in several seconds.

Basic instrument

The system is composed of an Aer'ODE software (validated and compliant FDA 21 CFR Part 11, ISO 11137, ...), a spectrophotometer, a thickness gauge (if needed) and a PC. Aer'ODE software totally controls the spectrophotometer and the thickness gauge to ensure the automatic setting of these measuring devices (Absorbance mode, Wavelength, zero of absorbance and zero unit for thickness).

User registration

The access to the different software functions for each user can be configurated in the general parameter section.

Each user has his own password and his own security level (Right limited to measurement of dose, the right to modify the calibration parameters, access to the database, control instruments...)

The logbook, automatically generates, traces all actions performed by user (operator, type of action, date, time...)

Calibration of the dosimetry system

The calibration curve changes significantly depending on the type and the batch of the dosimeter used (ISO/ASTM 51261)

With the readout equipments the Aer'ODE software and a batch of irradiated dosimeters (at doses known), the user can easily determine the calibration curve.

The software determines the best regression curve with F-ratio , R2 and Residual criteria according to ISO/ASTM 51707. The calibration parameters are stored directly in the database and are available for routine doses measurement without transcription errors.

Routine dose measurement

The software proposes single (FWT, Harwell, GEX, ...) or continuous dose measurements (CTA, Risö...) for dose profile purposes.

This last option gives a distribution of the absorbed dose by the strip of dosimeter with the maximum, the minimum and calculate the average dose.

The serial interfaces directly captures the reading parameters of the dosimeters (Absorbance, thickness). The specific absorbance (OD/t) is calculated through the PC. Based on the calibration curve previously stored in the database, a mathematical calculation allows determining the absorbed dose by the dosimeter in function of the calibrations parameters.

The continuous dose measurement mode allows to obtain an absorbed dose distribution by the dosimeter with the maximal, the minimal and the average value of the dose for a given region of the strip. In addition, a section of the software allows to evaluate the electron beam scanning length and its uniformity.

Electron beam energy evaluation

This procedure is also intended to irradiators implementing an electron accelerator. The continuous measure of dosimeter CTA, Risö B3 irradiated in a wedge of material (aluminium, polyethylen, polystyren ) according ISO/ASTM 51649 allows to evaluate the control parameters of the electron accelerator (most probable energy (Ea), average energy (E), Range (Rp), useful range (R50)...) for energies between 1 and 10 MeV.

Data storage

Following the operator's instructions, the analysis results are stored into the data base. This type of storage gives rapid and reliable access to the data saved at each level of the control systems (calibration, dose measurements, and instrument checks). In addition, data can be directly transferred to spreadsheets software like Excel or linked to a database (eg: Access) to perform additional paper work. A printer then issues the forms necessary for interpretation and storage of information. The files can be opened under Access or Excel.

Adaptations

It is important to note that the use of this device is characterized by a great flexibility. Moreover, Aérial can adapt the Aer'ODE software to the specific needs, requirements and readout instruments of the customer.

Efficiency - reliability

The principle of the Aer'ODE system is a major contribution to the efficient control of dosimetry in an irradiation plant.

Being fully automatic PC controlled, the system is time saving and reduces quite significantly the risk of dosimeter reading errors. As the software runs under Window NT, 2K, XP, Vista operating systems, it is also possible to integrate it into the global control system of a radiation unit.

Quality Assurance

Finally, its routine utilization in dosimetry laboratories contributes greatly to compliance with quality safe requirements in any field related to radiation. In this context, quality assurance specifications are provided with each analysis system so as to carry out the specified tests on a regular basis and ensure its good working condition.

More in this category: « Dos'ASAP