Calibration Services

Calibration Certificates

As an accredited dosimetry calibration laboratory, PTW-Freiburg is proud to offer calibration for most types of dosimetry equipment.

The calibration certificates can include the following data:

• Factory calibration for detectors or complete dosimetry systems (SSDL calibrations upon request)
• Calibration factor and check reading of radioactive check devices for atmospheric standard conditions

Correction factors for user-selected radiation qualities are available upon request.

The calibration certificates from PTW-Freiburg document the traceability to primary standards, which provide the reference for the units of measurement according to the International System of Units (SI).

Calibrations for the following measuring quantities are available:

• Absorbed energy to water D_w measured in Gray (Gy)
• Air Kerma K_a measured in Gray (Gy)
• Ambient equivalent dose H*(10) and  photon equivalent dose H_x measured in Sievert (Sv)
• Exposure J_s measured in Roentgen (R) - no SI unit

The standard procedure is factory calibration; formal DAkkS (SSDL) calibration can be performed upon request. The reference air pressure for calibration is 1013 hPa, and the reference ambient temperature can be 20 or 22 °C, which the user must specify. The uncertainties stated correspond to the double standard deviation (k = 2), calculated according to EAL-R2¹. If a radioactive check device is available, the check reading under standard conditions is stated on the calibration certificate.

¹ European Co-operation for Accreditation, Report No. 2, Edition 1, April 1997 "Expression of the Uncertainty of Measurement in Calibration

Radiation Qualities

A variety of ionizing radiation beam quality sets for different applications is available:

• Radiation Therapy Dosemeters
  • X-rays: 10, 15, 30, 50, 70, 100 kV
    (TW qualities according to DIN 6809-4)
  • X-rays: 70, 100, 140, 200, 280 kV
    (TW qualities according to DIN 6809-5)
  • ¹³⁷Cs (662 keV)
  • ⁶⁰Co (1.3 MeV)
    
    
• Diagnostic Radiology Dosemeters
  • Conventional X-rays: 40, 50, 70, 90, 120, 150 kV (RQR and RQA 3 / 5 / 7 / 9 / 10 according to IEC 61267)
  • CT: 70, 90, 120, 150 kV (RQR and RQA 5 / 7 / 9 / 10)
    100, 120, 150 kV (RQT 8 / 9 / 10 according to IEC 61267)
  • Mammography: 25, 28, 30, 35 kV
    (RQR-M and RQA-M 1 / 2 / 3 / 4 according to IEC 61267)
    and additional MAM radiation beam qualities (Mo/Rh, W/Al, W/Mo, W/Rh, Rh/Rh, W/Ag according to PTB)
  • Dental- X-rays: 50, 70, 90 kV 
    
    
• Radiation Protection Dosemeters
  • X-rays: 20, 30, 40 kV (Narrow Spectrum Series (N) qualities acc ISO 4037-1)
  • X-rays: 60, 80, 100, 150, 200, 250 kV (Narrow Spectrum Series (N) qualities acc ISO 4037-1)
  • ¹³⁷Cs (662 keV)
  • ⁶⁰Co (1.3 MeV)
    
    
• Miscellaneous Calibrations
  • Source strength (cGym²h^-1) of brachytherapy sources measured by well-type chambers
  • Diagnostic X-ray generator high voltage of all types of X-ray equipment measured non-invasively by kV-meters: Different ranges from 20 to 140 kV
  • Nuclide activity in nuclear medicine measured by isotope calibrators (only CURIEMENTOR instruments)
  • Electrical measuring quantities charge (C) and current (A) measured by highly sensitive electrometers

General Information: According to the PTW definition, each such set of beam qualities represents one calibration point for a certain application and can be ordered with a single order number.