Code of practice for personal dosimetry of professionals wearing protective clothing during radiolog

Dutch legislation implementing the EU Council Directive 96/29/Euratom, requires record keeping of the effective dose to employees who may be exposed to more than 1 mSv of ionising radiation per year. In practice, readings from personal dosemeters (HP(10)) are recorded in the national database (NDRIS) as an estimator of effective dose. However, the effective dose to professionals who wear protective clothing during exposure will be appreciably lower than HP(10) measured outside the apron. It is not unusual that individual employees of certain highly exposed categories apparently exceed the annual dose limit when the effective dose is based on such measurements. To improve the estimation of effective dose some national dosimetric services in the Netherlands apply a conversion factor to the readings before registration in NDRIS whereas others do not. This impairs comparison of recorded doses. Hence it is highly desirable to apply safe standard protocols to harmonise the interpretation of measured dose values. An important condition is that such protocols should balance correctness and simplicity to promote their acceptance and application by fieldworkers, local radiation safety officers, dosimetric services and the government.

The purpose of the research project that the NCS subcommittee “Loodschorten” (lead aprons) has carried out for the Dutch Ministry of Social Affairs and Employment was to derive protocols for proper personal dosimetry when protective clothing is worn. Questions that were to be answered comprise the current situation in the Netherlands and abroad; how to estimate effective dose best from the dosemeter reading; which categories of professionals and activities are involved; under which circumstances correction of dose values should be allowed and what conversion factor should then be applied; and, finally, what is the optimal wearing position of the dosemeter.

Concisely, the following is recommended in NCS Report 19. One group of professionals is identified with a high risk of exceeding the annual dose limit when personal dosemeters are not corrected. This is the group of health care workers in interventional radiology/cardiology. When performing routine medical procedures it would be sufficient to wear a single personal dosemeter. That dosemeter should be worn at a central position high on the chest and outside the apron. Depending on the thickness of the lead apron, and the presence or absence of a thyroid collar, a conversion factor in the range of 5 to 15 can be selected, dependent on specified conditions. The dosemeter reading must be divided by this factor to yield a reasonable estimate of effective dose. Both the converted and original dose are to be recorded in NDRIS.

Additionally, we added a reference to McCaffey et al 2012 in which the DIN norm is described how to assess the lead equivalence of composite aprons. 

https://doi.org/10.25030/ncs-019

 

The NCS frequently publishes reports for fellow professionals in which recommendations are given for various quality control procedures or otherwise. The members of the NCS board and the members of the concerning subcommittee do not claim any authority exceeding that of their professional expertise. Responsibility on how the NCS recommendations are implemented lies with the user, taking into account the practice in his/her institution.

NCS Reports See all files

Radiation Protection and Dosimetry of the Eye Lens

NCS 31, May 2018

+ More about and download

Code of Practice for Quality Assurance of Brachytherapy with Ir-192 Afterloaders

NCS 30, May 2018

+ More about and download

An on-site dosimetry audit for high-energy electron beams

NCS 29, October 2018

+ More about and download

National Audit of Quality Assurance for IMRT and VMAT

NCS 28, March 2018

+ More about and download

Quality Assurance for Tomotherapy Systems

NCS 27, April 2017

+ More about and download

Human Exposure to Ionising Radiation for Clinical and Research Purposes

NCS 26, May 2016

+ More about and download

Process Management and Quality Assurance for Intracranial Stereotactic Treatment

NCS 25, October 2015

+ More about and download

Code of Practice for the Quality Assurance and Control for Volumetric Modulated Arc Therapy

NCS 24, February 2015

+ More about and download

Audit of High-Energy Photon Beams in Belgian and Dutch Radiotherapy Departments

NCS 23, December 2013

+ More about and download

Code of Practice for the Quality Assurance and Control for Intensity Modulated Radiotherapy

NCS 22, June 2013

+ More about and download

Diagnostische referentieniveaus in Nederland

NCS 21, June 2012 (in Dutch with an English summary)

+ More about and download

Dosimetry and quality control of brachytherapy with low-energy photon sources (125I)

NCS 20, April 2012

+ More about and download

Code of practice for personal dosimetry of professionals wearing protective clothing during radiolog

NCS 19, October 2008

+ More about and download

Code of Practice for the Absorbed Dose Determination in High Energy Photon and Electron Beams

NCS 18, January 2008

+ More about and download

Dosimetrie in de Radiologie: Stralingsbelasting van de Patiënt en Werknemers

NCS 17, March 2007

+ More about and download

Monte Carlo Treatment Planning, An Introduction

NCS 16, June 2006

+ More about and download

Quality assurance of 3-D treatment planning systems for external photon and electron beams

NCS 15, March 2005

+ More about and download

Quality control of sealded beta sources in brachytherapy

NCS 14, August 2004

+ More about and download

Quality Control in Brachytherapy

NCS 13 November 2000

+ More about and download

Determination and use of scatter correction factors of megavoltage photon beams

NCS 12, March 1998, seel also NCS 15.
No revision required

+ More about and download

Quality Control (QC) of Simulators and CT scanners and some basic QC methods for Treatment Planning

NCS 11, September 1997, revision before 2020

+ More about and download

Dosimetry of low and medium energy X-rays

NCS 10, July 1997

+ More about and download

Quality control of medical linear accelerators: current practice and minimum requirements

NCS 9, August 1996, revision before 2020

+ More about and download

Kwaliteitscontrole van Medische Lineaire Versnellers, methoden voor kwaliteitscontrole

NCS 8, December 1995 (in Dutch), revision before 2020

+ More about and download

Dosimetric aspects of Mammography

NCS 6, March 1993

+ More about and download

Code of practice for the dosimetry of high-energy electron beams

NCS 5, December 1989

+ More about and download

Proceedings of the Symposium on Thermoluminescence Dosimetry

NCS 3, October 1988

+ More about and download

Code of practice for the dosimetry of high-energy photon beams

NCS 2, December 1986

+ More about and download

Radiation dosimetry activities in the Netherlands

NCS 1, July 1986

+ More about and download