title: Development of a risk-based acceptance index to support design of compressed natural gas vehicle
Creators: name: Altuwair, Ibrahim A.
Publisher: name: Memorial University of Newfoundland
Year: 2020

description: The research aims to develop a risk-based acceptance index (RBAI) for the assessment of compressed natural gas (CNG) onboard vehicle and discover the reason why an accident occurred and alleviate the risk aversion towards high-pressure applications onboard such as CNG, H2, and LPG. It is offering a proactive way to identify and resolve safety issues. A good understanding of CNG properties requires an evaluation of the associated threat with CNG onboard is essential. Existing standards, specifications, regulations, and designing guidelines need to examine for safety purposes with consideration for the applicability to a specific design. Safety professionals have attribute about (70-80%) to human faults. Human is an important factor in the cause of accidents. As the design of overpressure storage tanks becomes safe, the accidental causes are becoming more likely to be attributed to the human factor. Recent traffic accidents have left the public wondering how an overpressure system with the potential to harm the end-user and public could have operated onboard of vehicle. No hazard analysis can be used during the design phase of a CNG cylinder onboard to identify and evaluate hazardous scenarios involving human error. Human cognitive characteristics guideword could stimulate safety professionals to consider the suitability of various system aspects for human use from a perception point of view. Professionals must consider the impact of the human perception factor on safety. It intended to be helpful and practical for teasing out the human and system design flaws that can lead to hazards. In the next chapters, the integration of human guideword into RBAI will be used for the risk analysis. As a case study, an introduction to the overpressure calculation and the consequences to the material damages presented. An unintentional rupture filled with CNG would generate a rapid energy release in the form of the pressure energy (blast) studied. The procedures described are practical and attempt to give a perfect understanding of the subject and help to understand the meaning of all the variables by performing SPSS-Amos code. The research concluded with a discussion on the possible cause and effect that influence the end user's decision of choice. Therefore, the research has divided into two parts; the first part includes developing an acceptance index to support the design of compressed natural gas (CNG). This part consists of three chapters; chapter one, including introduction, research goal, and the use of acceptance index for risk assessment. Chapter two provided the background related to the acceptance index and literature reviewed concerning the CNG cylinder. Chapter three illustrated the methodology of the experiment that focused on aspects associated with the experimental parameters. It includes design questionnaires, data collection methods, data processes, and data analysis. The second part of the research divided into three chapters. Chapter four described the ethical considerations and approval process, including all required letters of approval for the feasibility of the acceptance index with designing CNG onboard vehicles. Chapter five addresses the theoretical background and some fundamentals related to the risk assessment and proposed method. In contrast, chapter six considers the application of compressed natural gas and mechanical effect as a case study. Lastly, chapter seven is performing SPSS for data gathering and analysis.