In recent decades, many accidents involving pressure vessels and piping components (PVP) have occurred in North America. Several studies have been conducted to understand their causes and find suitable solutions to reduce their frequency. Most of the researches have focused on the technical causes of these accidents and the subsequent implementation of safety management strategies. These researches highlight that the main technical causes are leak and rupture. From this standpoint, it is important to deepen the study of these causes to better understand the risk of accident in PVP applications. In Alberta alone, the Alberta Energy Regulator (AER) showed that more than 15 root causes initiated leak and rupture failures in PVP since 1990. This paper presents an analysis of the frequency of accidents, their severity, their causes, and the risk associated in the Alberta petrochemical industry from 2008 to 2017. This study proposes an exponential decay function to estimate the frequency of accidents involving PVP and identifies the most important causes based on a severity analysis. The results based on the frequency model show that there is a good agreement between the predicted and observed accidents frequency from 2008 to 2017. The severity analysis results shows that the main factors contributing to accidents are corrosion, construction deficiency, and overpressure. Finally, the proposed model of frequency and severity of observed and predicted PVP failures, is a useful tool for risk assessment and prevention program implementation.

In recent decades, many accidents involving pressure vessels and piping components (PVP) have occurred in North-America. Several studies have been conducted to understand their causes and find suitable solutions to reduce their frequency. Most of the researches have focused on the technical causes of these accidents and the subsequent implementation of safety management strategies. These researches highlight that the main technical causes are leak and rupture. From this standpoint, it is important to deepen the study of leaks and ruptures accidents. In Alberta alone, the Alberta Energy Regulator (AER) demonstrated that more than 15 root causes initiated leak and rupture failures in PVP since 1990. This paper presents an analysis of the frequency of accidents, their severity, their causes and the risk associated in the Alberta petrochemical industry from 2008 to 2017. This study proposes an exponential decay to estimate the frequency of accidents involving PVP and identifies the most important causes based on a severity analysis. The results based on the developed model show that there is a good agreement between the predicted and observed accidents frequency from 2008 to 2017. The severity analysis results show that the main factors contributing to accidents are corrosion, construction deficiency and overpressure. Finally, the proposed model of frequency and severity of observed and predicted PVP failures needs improvements to better predict the risks and be useful for prevention.

Continuity of production and employee safety are the two main concerns of today's modern, automated, or intelligent factories. To increase safety and decrease risks in hostile working environments, manufacturers must comply with laws and regulations that are implemented in codes and standards. Unfortunately, even though companies comply with these laws and regulations and use the latest technologies, tragic accidents involving pressure vessels and piping still occur. Two such, recent events occurred in North America: in Canada, the pipeline spill of Journey Energy Inc. in 2017 and in the United States, the ExxonMobil refinery explosion in 2016. The storage of a fluid under pressure can represent a serious risk of dangerousness, not only to the employees, but also to the emergency services, the population in the vicinity and the environment. Currently, the technical aspects are the main concern of regulatory authorities (TSSA O. Reg. 220/01, RBQ B-1.1, r. 6.1, US National Board of Boiler and Pressure Vessel Inspectors (NBBI)) and the scientific community is focused on risk assessment related to structural integrity and leak tightness. The present paper surveys 50 accident cases that occurred in Canada and the United States from 1997 to 2017 related to pressure vessels and piping in petrochemical and nuclear industries. The causes of these accidents are various, but the authors focus on those related to a non-compliance with the applicable standards, namely CSA and ASME. The accidents are analyzed using a risk-ranking network and Venn diagram. Furthermore, using a case study, an in-depth analysis of an accident of a miniature boiler involving non-compliance with procedures, laws, regulations, code, and standards is conducted. The analysis of two-thirds of the documented accidents revealed that the main cause was of an organizational nature: non-compliance with standards, violation or absence of health and safety management, training deficiency, noncompliance with work procedures, and lack of clear and detailed maintenance procedures.