Radiation
is ubiquitous. All humans are exposed to natural background radiation
consisting of cosmic radiation, cosmogenic radionuclides and terrestrial radiation
from the radioactive materials present in the earth. In addition to this,
humans are also exposed to artificial or man-made radiation sources. In all,
globally on an average, the annual radiation dose due to these sources works
out to be around 2.4 mSv. The levels of natural radionuclides are enhanced
significantly in situations where the materials are processed in industrial
scale to obtain useful materials such as uranium, thorium, rare-earth elements,
etc.
This
reference book entitled “Radiological Protection and Safety – A Practitioner’s
Guide” is designed to guide persons involved or related to radiological
protection, i.e., Health physicists (HPs), Radiological Safety Officers (RSOs)
and Medial health physicists who, by and large serve as a link between the
facility or installation management and the regulators, to ensure radiological
protection and safety. This resource book is also useful to researchers,
trainers, students, the radiological and nuclear facility operators, the
regulators and personnel undergoing training in fields dealing with radiation
and radioisotopes. Training of the personnel in radiological protection and
safety forms the focus of radiation protection programmes and creates an
awareness to remove inherent radiophobia or fear of radiation amongst educated
and other members of the public. This is important in the current scenario of potential
of nuclear terrorism world-wide.
Occupational
workers are those who are exposed to radiation during the course of their
work. The concepts of radiological
protection, radiation protection standards, regulations as well as the exposure
control techniques are changing over time. This reference book, organized in
about 350 pages and in 19 chapters, covers radiological protection and safety
aspects in life cycle of nuclear fuel cycle facilities. It also covers current
status of the issues and topics of concern in the wide variety of applications
of radiation and radioisotopes, particularly technological developments in
medicine and industry. The occupational risk of harm needs to be acceptable in
comparison with the risks in other industries which are considered as
safe.
Radiation
protection is a multi-disciplinary subject. The ICRP system of radiological
protection is applicable to all facilities and activities involving radiation
sources or radioactive materials with potential for occupational exposures. In
general, from a regulatory perspective, the nuclear fuel cycle operations,
i.e., starting with mining of the natural uranium, milling, reactor fuel
production, the fuel fabrication, nuclear reactor operation, the spent-fuel
reprocessing and the radioactive waste management, are well covered and
generally under the regulatory control of the government. However, the use of
radiation and radioisotopes are being increasingly used in public domain in
medicine and industry posing newer challenges. There are numerous techniques in
medical diagnosis and therapy where patients are exposed to radiation for medical
diagnosis and therapy. However, these techniques also occupationally expose the
physicians, the radiologists, the paramedical staff, the technicians, the care
takers and the public at large, to the radiation.
In
addition to the peaceful uses of radiation, there is a threat of terror
organizations using orphan, stolen or disused radiation sources to harm
civilians and others by malicious use of the sources in many forms such as
Radiological Dispersal Devices (RDDs). Nuclear and
radiological emergency is considered important and is separately covered in the
chapter on radiological safety in emergency exposure situations. The
types of emergency situations, the preparedness and response are discussed in
the book with latest references. Security of the radiation sources and
radioactive materials is currently a concern, which is being addressed by
international and national bodies. Relevant references are provided on the
subject for the information of all concerned.
The
UNSCEAR periodically provides comprehensive data on levels and effects of
radiation exposures in different applications of radiation and radioisotopes.
International Commission on Radiological Protection (ICRP) reviews the inputs
from various sources, including epidemiological studies on the exposure of
groups of population and experimental findings and provides basic
recommendations periodically. Recent Most recommendations are published in
ICRP-103, 2007.
Wherever
possible, references are provided for the numbers used. As always happen in the
health physics profession, informed judgements/thumb rules, based on decades of
operational radiation protection experience have provided adequate level of
safety required in the profession. As per the educationist David A. Kolb,
learning is a process whereby knowledge is created through the transformation
of experience.
In
order to contain the size of the reference book to be “acceptable” for the
readers, brevity has been an important consideration to include most of the
topics of relevance to radiological protection and safety. References of
radiological significance in the topics are provided at the end of each chapter,
to be pursued by the reader for further details.
The
reference book will be useful to all stakeholders in the nuclear industry who
would like to refer to one book to know about all aspects of radiological
safety in the application of radiation and radiation sources for the benefit of
people. I dedicate this book to the radiation protection community, who work
tirelessly to protect people and the environment from the harmful effects of
radiation exposures.
