dc.contributor.author |
Rahman, Said |
|
dc.date.accessioned |
2017-11-28T07:18:36Z |
|
dc.date.accessioned |
2020-04-14T19:31:55Z |
|
dc.date.available |
2020-04-14T19:31:55Z |
|
dc.date.issued |
2008 |
|
dc.identifier.uri |
http://142.54.178.187:9060/xmlui/handle/123456789/7859 |
|
dc.description.abstract |
Radon has long been recognized as one of the indoor air problems. There is a strong
relation between radon and lung cancer. It is the second leading cause of the lung cancer
after cigarette smoking. The present research work concerning the Measurement of
seasonal and spatial variation of indoor radon and development of a passive
dosimeter for thoron’s progeny is divided into two parts. The first part deals with the
field and laboratory measurements which were performed using the passive radon
dosimeters and in the second part laboratory experiments were carried out to develop a
new passive thoron progeny dosimeter.
Chapter 1 gives a brief introduction to radon, its health effects, measurement
techniques and the instruments used for the measurement of indoor radon concentration.
Different dose conversion relations and excess lung cancer reports have also been
discussed in this chapter. Chapter 2 describes different types of equipments and materials
used in the research work. Information about the geology, climatic conditions and
building characteristics of the houses surveyed have also been given in this chapter. It
also includes procedure of the samples preparation for the measurement of radioactivity
and radon exhalation rate in the laboratory using active and passive detectors. In chapter
3 reviews reported studies conducted in Pakistan concerning the measurement of natural
radioactivity and indoor. Chapter 4 discusses the results and discussion of the present
work concerning radon measurement performed throughout the years in four cycles
which has covered all the seasons. Seasonal correction factor, weighted average indoor
radon levels excess lung cancer risk and the dose delivered to the inhabitants using the
local occupancy factor have also been included in this chapter. Chapter 5 deals with the
results and discussions about the radon exhalation from the soil, sand and brick samples
which were collected from the selected area. Effect of moisture contents on the radon
exhalation rate using a closed can technique has also been presented in the chapter. The
effect of back diffusion on the radon exhalation has also been studied and included in this
chapter. Measurement of the natural radioactivity in the soil and other building materials,
1like sand, brick, marble and cement samples which were collected form the selected area
has been dealt with in chapter 6.
Research work performed at the University of St., John University USA has been
included in chapter 7 and 8. These chapters include experiments performed in the
exposure room using the electret ion chambers. Radon concentration in the exposure
room was measured using both short term and long term electrets. It also includes the
results of the performance factor for the alpha contamination chambers using the electrets
as radon progeny dosimeter. Experiments were performed using both short term high
sensitivity and long term (low sensitivity) electrets. Development of a new passive thoron
progeny dosimeter using the principle of the surface deposition has been discussed in
chapter 8. This chapter includes an introduction about the different types of active and
passive equipments used for the measurement of thoron. It also discusses the calibrations
of different types of active detectors for the measurements of surface deposited activities
on the glass surfaces. Finally chapter 9 concludes the present research work and includes
future recommendations. |
en_US |
dc.description.sponsorship |
Higher Education Commission, Pakistan |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
Pakistan Institute of Engineering and Applied Sciences (PIEAS) Nilore, Islamabad 45650, Pakistan |
en_US |
dc.subject |
Natural Sciences |
en_US |
dc.title |
Measurement of Seasonal and Spatial Variation of Indoor Radon and Development of a Passive Dosimeter for Thoron’s Progeny |
en_US |
dc.type |
Thesis |
en_US |