Ionization chamber for the direct measurement of the personal dose equivalent, H_p(10), in the energy range between 12 keV and 1,4 MeV and in the angular range from 0° to 75°. Specially suited for the dosimetric calibration of X-ray facilities in the energy range below 100 kV accelerating voltage.

Literature:

• Ankerhold, U., Behrens, R., Ambrosi, P.:
  A prototype ionisation chamber as a secondary standard for the measurement of personal dose equivalent, H_p(10), on a slab phantom
  Radiat. Prot. Dosim., Vol. 86, No. 3, pp. 167-173 (1999)

Contact:

Dr. Hayo Zutz
phone: +49 (0) 531-592-6310

Distribution: PTW-Freiburg

Costs for Calibration

BSS 2 beta secondary standard for carrying out irradiations using beta radiation of mean energies between 60 keV and 800 keV. The radiation qualities are in compliance with the series of standards ISO 6980.

The BSS 2 can be obtained from Eckert & Ziegler Nuclitec GmbH. The manual is available.

For the users of the BSS 2, the file "BetaFakt.ini" is available, this file contains several correction factors used by the software of the BSS 2.
Several letters containing user information have been made available by PTB in the past. Some of them are not relevant any more. However, for the sake of completeness all are made available.

Literature:

• Behrens, R.:
  Energy-reduced beta radiation fields from ⁹⁰Sr/⁹⁰Y for the BSS 2
  Journal of Instrumentation, Vol. 15, PO5015 (2020)
• Behrens, R.:
  Correction factors for the ISO rod phantom, a cylinder phantom, and the ICRU shere for reference beta radiation fields of the BSS 2
  Journal of Instrumentation, Vol. 10, P03014 (2015)
• Behrens, R.:
  Simulation of the radiation fields of the Beta Secondary Standard BSS 2
  Journal of Instrumentation, Vol. 8, P02019 (2013)                                                                                Addendum: Journal of Instrumentation, Vol. 14, A07001 (2019)
• Behrens, R., Buchholz, G.:
  Extensions to the Beta Secondary Standard BSS 2, Journal of Instrumentation
  Vol. 6, P11007 (2011) and Erratum and Addendum
  
• Behrens, R., Hilgers, G.:
  Photon spectra from beta sources of the Beta Secondary Standard BSS 2
  Journal of Instrumentation, Vol. 6, P09006 (2011)
• Bruzendorf, J.:
  Depth-dose curves of the beta reference fields ¹⁴⁷Pm, ⁸⁵Kr and ⁹⁰Sr/⁹⁰Y produced by the beta secondary standard BSS2
  Rad. Prot. Dosim. 151, 211 (2012)
  
• Brunzendorf, J.:
  Determination of depth-dose curves in beta dosimetry
  Rad. Prot. Dosim. 151, 203 (2012)
• Ambrosi, P., Buchholz, G., Helmstädter, K.:
  The PTB Beta Secondary Standard BSS 2 for radiation protection
  Journal of Instrumentation, Vol. 2, P11002 (2007)
• Helmstädter, K., Buchholz, G., Ambrosi, P.:
  Das PTB Beta-Sekundärnormal BSS 2 für den StrahlenschutzPTB-Bericht: PTB-Dos-50 (2006),
  ISBN: 3-86509-495-3
• PTB-news 97.1

Contacts:
dosimetric matters:
Dr. Rolf Behrens
phone: +49 (0) 531-592-6340

technical matters:
Dipl.-Ing. Jürgen Roth
phone: +49 (0) 531-592-6350

Distribution:
Eckert & Ziegler Nuclitec GmbH
Enrico Raus
phone: +49 (0) 5307-932-235

The Calibration of the radiation sources is carried out at PTB in the department.

The International Commission on Radiological Protection (ICRP) has reduced their recommended dose limit for the eye lens from 150 mSv down to 20 mSv per year for occupational exposure (www.icp.org//page.asp?id=123). Detailed information is available in ICRP 118. This recommendation has been adopted in the European directive 2013/59/EURATOM and consequently, in national law for all EU member states. Therefore, several investigations regarding eye lens dosimetry have been carried out. This part of the report focuses on PTB’s activities since then.

First it is advisable to think about the quantity to be used for the purpose under consideration:

• R. Behrens and G. Dietze: Monitoring the eye lens: Which dose quantity is adequate? Phys. Med. Biol. 55, 4047 (2010) and Phys. Med. Biol. 56, 511 (2011)
• R. Behrens: Monitoring the Eye Lens, IRPA13-Beitrag: TS7e.3

In pure photon radiation fields, H_p(0.07) may be used. Then, extremity dosemeters are suitable when worn near the eye and in case they detect radiation scattered back from the head. After this, they can be calibrated on both the ISO water slab phantom and the ISO polymethyl methacrylate (PMMA) rod phantom:

• R. Behrens, J. Engelhardt, M. Figel, O. Hupe, M. Jordan, and R. Seifert: H_p(0.07) photon dosemeters for eye lens dosimetry: Calibration on a rod vs. a slab phantom, Rad. Prot. Dosim. 148, 139 (2012)

In case beta radiation significantly contributes to the dose, H_p(3) is advisable:

• R. Behrens: On the operational quantity H_p(3) for eye lens dosimetry, J. Radiol. Prot. 32 (2012), 455-464. In short: The slab phantom is for calibration at normal radiation incidence as appropriate as the cylinder phantom.

For H_p(3) dosemeters, both the slab and the cylinder phantoms are suitable for calibration (usually at 0°). However, type tests (especially above 30° radiation incidence) should be carried out on a cylinder phantom:

• R. Behrens and O. Hupe: Influence of the phantom shape (slab, cylinder or Alderson) on the performance of an H_p(3) eye dosemeter Rad. Prot. Dosim., 168, 441 (2016)

The following papers give conversion coefficients from air kerma to H_p(3) for the slab phantom and cylinder phantom; thus, enabling the performance of photon calibrations and irradiations in terms of H_p(3):

• R. Behrens: Air kerma to dose equivalent conversion coefficients not included in ISO 4037-3, Rad. Prot. Dosim. 147, 373 (2011)
• R. Behrens: Air kerma to H_p(3) conversion coefficients for a new cylinder phantom for photon reference radiation qualities, Rad. Prot. Dosim. 151, 450 (2012)

Photon area dosemeters can be irradiated or calibrated in terms of H′(3), as conversion coefficients from air kerma to H′(3) for the ICRU sphere are available for both mono-energetic photons as well as for radiation qualities according to ISO 4037:

• R. Behrens Conversion coefficients for H′(3;Ω) for photons J. Radiol. Prot. 37, 354 (2017)

Likewise, beta dosemeters can be irradiated or calibrated in terms of H_p(3) and H′(3), as the Beta Secondary Standard, BSS 2, has been extended:

• R. Behrens and G. Buchholz: Extensions to the Beta Secondary Standard BSS 2, Journal of Instrumentation, Vol. 6, P11007 (2011)
• Further information on the BSS 2 is available on PTB’s website.

Investigations in nuclear medicine yielded dose rate constants of beta-photon nuclides as well as the shielding effect of goggles for beta-photon nuclides:

• B. Szermerski et al.: Dose rate constants for the quantity H_p(3) for frequently used radionuclides in nuclear medicine, Z. Med. Phys. 26 (2016) 304
• I. Bruchmann et al.: Impact of radiation protection means on the dose to the lens of the eye while handling radionuclides in nuclear medicine, Z. Med. Phys. 26 (2016) 298

Conversion coefficients from fluence to the equivalent dose to the lens of the eye, H_lens, are given in the following papers:

• R. Behrens, G. Dietze, and M. Zankl: Dose conversion coefficients for electron exposure of the human eye lens (just one eye as phantom), Phys. Med. Biol. 54, 4069 (2009) and corrigendum Phys. Med. Biol. 55, 3937 (2010)
• R. Behrens: Dose conversion coefficients for electron exposure of the human eye lens: Calculations including a full human phantom, Rad. Prot. Dosim. 155, 224 (2013)
• R. Behrens and G. Dietze: Dose conversion coefficients for photon exposure of the human eye lens, Phys. Med. Biol. 56, 415 (2011)
• R. Behrens: Compilation of conversion coefficients for the dose to the lens of the eye Rad. Prot. Dosim. 174, 348 (2017)

At least two comparisons for eye lens dosemeters in terms of H_p(3) were conducted, a third one is currently being carried out:

• R. Behrens et al.: Intercomparison of eye lens dosemeters, Rad. Prot. Dosim. 174 (2017) 6
• I. Clairand et al.: EURADOS intercomparison exercise of eye lens dosemeters, Rad. Prot. Dosim. 182 (2018) 317
• EURADOS Intercomparison 2019 for extremity and eye lens dosemeters (IC2019exteye)

Since ICRP recommended the reduced dose limit for the lens of the eye in 2011, and partly even before, international organizations started several actions. Among them are EURADOS as well as IAEA:

• EURADOS project: Optimization of RAdiation protection for MEDical staff (ORAMED) with a detailed final report as well as several scientific papers
• Information on IAEA’s website on both medical staff as well as patients.

Furthermore, several international documents have already been adopted or are currently being revised to implement the operational quantities H_p(3) and H'(3):

• IEC 61331-3: Requirements to medical protective equipment (2014)
• ISO 4037: Photon reference radiation fields (2019)
• ISO 6980: Beta reference radiation fields (2004 – currently in revision)
• IAEA TecDoc 1731: Dosimetry in practice (2013)
• ISO 15382: Dosimetry in practice (2015)
• IEC 62387: Requirements to dosemeters (passive) (2020)
• IEC 61526: Requirements to dosemeters (active) (2010 – currently in revision)
• ISO 14146: Routine test for dosemeters (2018)

List of publications

• Conversion coefficients for mono-energetic electrons: Φ to H_lens: Phys. Med. Biol. 54 (2009) 4069 & Phys. Med. Biol. 55 (2010) 3937 & Rad. Prot. Dosim. 155 (2013) 224
• Conversion coefficients for mono-energetic photons: Φ to H_lens: Phys. Med. Biol. 56 (2011) 415
• Compilation of conversion coefficients Φ to H_lens: Rad. Prot. Dosim. 174 (2017) 348
• Monitoring the eye lens: Which dose quantity is adequate? Phys. Med. Biol. 55 (2010) 4047 & Phys. Med. Biol. 56 (2011) 511 & J. Radiol. Prot. 32 (2012) 455 & IRPA13 contribution TS7e.3
• Conversion coefficients for photon spectra: K_a to H_p(3)_slab: Rad. Prot. Dosim. 147 (2011) 373
• Conversion coefficients for photon spectra: K_a to H_p(3)_cyl: Rad. Prot. Dosim. 151 (2012) 450
• Conversion coefficients for photon spectra: K_a to H'(3): J. Radiol. Prot. 37 (2017) 354
• H_p(0.07) photon dosemeters: Calibration on both rod and slab phantom: Rad. Prot. Dosim. 148 (2012) 139
• Type tests only on cylinder phantom: Rad. Prot. Dosim. 168 (2016) 441
• Beta irradiations in H_p(3) and H'(3): Extensions to the Beta Secondary Standard BSS 2: J. Instrum. 6 (2011) P11007 & Erratum & Addendum
• Dosemeter tests: Photon fields: H_p(0.07) and H_p(3) dosemeters perform well Beta fields: H_p(0.07) dosemeters overestimate H_lens up to a factor of 5000 Rad. Prot. Dosim. 174 (2017) 6 Rad. Prot. Dosim. 182 (2018) 317
• Nuclear medicine:
• Dose rate constants of beta-photon nuclides: Z. Med. Phys. 26 (2016) 304
• Absorption of googles for beta-photon nuclides: Z. Med. Phys. 26 (2016) 298
• Final report of the ORAMED project
• ICRU proposal for new operational quantities: Rad. Prot. Dosim. 180 (2017) 10

Contact

Dr. Rolf Behrens
phone: +49 (0) 531-592-6340

Determination of the spectral photon flux of X-radiation fields with the aid of a high-purity germanium semiconductor detector.
The measured spectra are available in ASCII format.

Literature:

• ANKERHOLD, U., BEHRENS, R., AMBROSI, P.:
  X-ray spectrometry of low energy photons for determining conversion coefficients from air kerma, K_a, to personal dose equivalent, H_p(10), for radiation qualities of the ISO narrow spectrum series
  Radiat. Prot. Dosim., Vol. 81, No. 4, pp 247-258 (1999)
  
  
• ANKERHOLD, U.:
  Catalogue of X-ray spectra and their characteristic data -ISO and DIN radiation qualities, therapy and diagnostic radiation qualities, unfiltered X-ray spectra-
  PTB report: PTB-Dos-34 (2000), ISBN: 3-89701-513-7
  

Contact:

Dr. Oliver Hupe
phone: +49 (0) 531-592-6300

Instrument for measuring the energy and angular distribution of radiation fields at workplaces. Measuring ranges: 30 keV to 300 keV and three independent angular ranges in the front half-space.

Literature:

• Alt, R., Ambrosi, P., Böhm, J., Hilgers, G., Jordan, M., Ritzenhoff, K.-H.:
  The generation of the response matrix of hemispherical CdTe detectors
  Nuclear Instruments and Methods in Physics Research A353 (1994) 71
  
  
• Ambrosi, P., Hilgers, G.:
  Strahlungsfelder und Expositionsbedingungen an Arbeitsplätzen
  Strahlenschutzpraxis 4/99 (1999) 53

Contact:

Dr. Gerhard Hilgers
phone: +49 (0) 531-592-6620

Individual dosemeters suitable for the official monitoring of persons occupationally exposed to radiation. Measurement of both, the old and the new quantities applicable in radiation protection (depending on the evaluation method chosen).

Literature:

• Ambrosi, P., Böhm, J., Hilgers, G., Jordan, M., Ritzenhoff, K.-H.:
  The gliding-shadow method and its application in the design of a new film badge for the measurement of the personal dose equivalent H_p(10)
  PTB-Mitteilungen 104 (1994) 334

• Ritzenhoff, K.-H., Jordan, M., Hilgers, G., Böhm, J., Ambrosi, P.:
  A new film badge for the measurement of the personal dose equivalent H_p(10) using the gliding-shadow methodProceedings of the 9. International Congress on Radiation Protection, Wien 1996, Vol.4, 266

Contact:

Dr. Hayo Zutz
phone: +49 (0) 531-592-6310

Dosimetry service in Dortmund

A TLD-based instrument for measuring the energy distribution in high-intensity electron and photon radiation fields (also pulsed radiation) in the energy range between 400 keV up to a maximum of 100 MeV (electrons) and between 20 keV and 2 MeV (photons).

A version for photons up to 100 keV is available.

Literature:

• Behrens, R.; Hufschmidt, P.; Roth, J.; Akstaller, B.; Haag, D.; Hupe, O.; Schmidt, S.; Schreiner, S.; Michel, T.:
  Radiation measurements and simulations at the PHELIX laser facility, GSI
  Journal of Instrumentaion, Vol. 17, P05033 (2022)

• Behrens, R.; Zutz, H.; Busse, J.:
  Spectrometry of pulsed photon radiation
  J. Radiol. Prot., Vol. 42, 011507 (2022)

• Behrens, R.:
  A spectrometer for pulsed and continuous photon radiation
  Journal of Instrumentaion, Vol. 4, P03027 (2009)
  
  
• Behrens, R.; Schwoerer, H.; Düsterer, S.; Ambrosi, P.; Pretzler, G.; Karsch, S.; Sauerbrey, R.:
  A thermoluminescence detector-based few-channel spectrometer for simultaneous detection of electrons and photons from relativistic laser-produced plasmas
  Review of Scientific Instruments, Vol. 74, Number 2, pp 961 - 968 (2003)
  
  
• Behrens, R.
  Wenig-Kanal-Spektrometer zur Messung von Elektronen- und Photonenspektren in ultrakurz gepulsten Strahlungsfeldern, ISBN 3-86509-002-8
  Dissertation: Physikalisch-Technische Bundesanstalt (PTB), (2003)
  Direct link to PDF-file
  
  
• Behrens, R.; Ambrosi, P.:
  A TLD-based few-channel spectrometer for mixed photon, electron and ion fields with high fluence rates
  Radiat. Prot. Dosim., Vol. 101, No.1-4, pp 73 - 76 (2002)
  
  
• Schwoerer, H.; Gibbon, P.; Düsterer, S.; Behrens, R.; Ziener, C.; Reich, C.; Sauerbrey, R.:
  MeV X Rays and Photoneutrons from Femtosecond Laser-Produced Plasmas
  Phys. Rev. Let., Vol. 86, No.11, pp 2317-2320 (2001)
  
  
• Nolte, R.; Behrens, R.; Schürer, M.; Rousse, A.; Ambrosi, P.:
  A TLD-based few-channel spectrometer for X-ray fields with high fluence rates
  Radiat. Prot. Dosim., Vol. 84, No.1-4, pp 367-370 (1999)

Contact:

Dr. Rolf Behrens
phone: +49 (0) 531-592-6340

TLD-based dosemeter badge for the measurement of the ambient dose equivalent, H*(10). The dosemeter meets the requirements of the standard DIN 25 483 "Methods for environmental monitoring using integrating solid-state dosemeters" in the dose range from 50 µSv to 10 Sv, in the energy range from 24 keV to 3 MeV and for all angles of incidence.

Literature:

• Ahlborn, M.:
  Das Thermolumineszenz (TL) Dosimetrie-System ALNOR DOSACUS
  Laboratory report PTB-6.51-98-1 (1998)
  
  
• Behrens, R.; Ambrosi, P.:
  Anwendung eines Verfahrens zur Umgebungsüberwachung mit integrierenden Festkörperdosimetern
  PTB-Bericht: PTB-Dos-46 (2004), ISBN: 3-86509-101-6

Contact:

Dr. Rolf Behrens
phone: +49 (0) 531-592-6340

Die in allen Funktionen über einen Rechner steuerbare Ladungsmesseinrichung besteht neben einer Zeitsteuerung aus Integrator- und Hochspannungseinschüben. Es stehen 6 Ladungsbereiche von 20 pC bis 2 µC zur Verfügung (Eingangsruhestrom < 3 fA). Die Hochspannungseinschübe liefern Spannungen von 0 V bis ± 660 V.

Schriften:

• Buchholz, G.:
  Ladungsmesser
  PTB-Bericht: PTB-EW-12 (2004), ISBN: 3-86509-158-x

Ansprechpartner:
Jürgen Roth
Tel.: 0531-592-6350 

Zur Messung von Strömen < 10 fA wurde für die oben beschriebene Ladungsmesseinrichtung ein Integrator mit einem Eingangsruhestrom < 0,5 fA entwickelt. Der Integrator ist in allen Funktionen über einen Rechner steuerbare. Es stehen 2 Ladungsbereiche von 20 pC und 200 pC zur Verfügung.

Schriften:

• Buchholz, G.:
  Hochempfindlicher Ladungsmesser
  PTB-Bericht: PTB-EW-15 (2013), ISBN: 978-3-95606-048-9

Ansprechpartner:
Jürgen Roth
Tel.: 0531-592-6350