Assessment Of Radiation Protection Practices Among Industrial Radiography Personnel - A Case Study Of Saipem Contracting Nigeria Limited

Reports of high radiation-related accidents have been associated with industrial radiography than in any other radiography sub-specialty, mainly due to breach of radiation protection practices. This study examines the availability and utilization of radiation monitoring devices, the means of environmental protection during field  operations and the commonly used radiation sources in Saipem Contracting Nigeria limited (SCNL). A descriptive survey design was adopted and convenience sampling technique was used in selecting both the study company and study sample. The respondents responded to a 32 item structured instrument in form of interview guide containing questions  on the availability, utilization, means of environmental protection from radiation as well as commonly used radiation sources. Critical ratio test was performed and used in testing the hypotheses. The findings show that radiation monitoring devices are available and are utilized during field operations. Findings also show that x-ray machines and radionuclide are the commonly used sources of radiation and that there is adequate source-operator distance during operation as well as a means of protecting the environment during field operation.  The study recommends that basically trained Radiographers be incorporated into SCNL and that constant update courses on radiation protection be organized for all the NDT staff irrespective of their rank. The study also recommends that the use of various radiation monitoring devices be strongly adhered to.

 

CHAPTER ONE

INTRODUCTION

THEORETICAL BACKGROUND

RESEARCH METHODOLOGY

DATA ANALYSIS, PRESENTATION AND DISCUSSION

DISCUSSION, CONCLUSION, RECOMMENDATION AND LIMITATIONS

Appendix 

Questionnaire 

Industrial radiography uses x-rays and Gamma rays to produce a radiograph of specimen or material, showing any changes in thickness, defect (internal or external), and assembly details, to ensure optimum quality. This application is called Non-destructive testing.1

Three types of radiation sources are typically available for such purposes.

Industrial radiography machines which are x-ray tube based can produce dose rates in air of about 2Gy per minutes at one metre. These machines are usually portable or mobile and convenient for use in a wide range of conditions such as at air craft hangers, pipeline construction and deployment, fabrication facilities, offshore platforms operations, bridges or construction sites.  At work sites, the working conditions coupled with frequent manipulation of such high-intensity radiation sources present much potential for radiation exposure to occur. Both the workers and other persons proximal to the work area can be exposed to high radiation fields which, potentially could lead to injuries or death.2

In another industrial application, there are systems specifically designed to focus intense beam of high energy electrons that melt and bond metal under vacuum conditions and these electron-metal interactions can produce x-rays as a by-product of the bonding process. Such systems are called Electron beam welders. Beam current and high voltages are typically in the range of 20-200milliAmpers and 120-450kilovoltage respectively. Consequently, the operations of electrons beam welders present a potential for exposure to x-rays and electrons, which are types of ionizing radiation.

  In general, the interaction of ionizing radiation with matter is probabilistic, that is, there may or may not be an interaction. The interaction with individual cells of living organisms may be direct or indirect. At the cellular level, direct interaction with Deoxyribonucleic acid (DNA), or other constituents can cause damages. Various possibilities exist for the fate of cells exposed to ionising radiation.

Thus, exposure to ionising radiation has the potential to cause early or late adverse health effect. This is why the radiation risks associated with industrial radiography operations need to be managed. This study is designed to ascertain the radiation protection procedures adopted by Saipem Contracting Nigeria Limited (SCNL)