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Due to the large quantities of hazardous materials stored and processed, chemical and process plants may be attractive targets for security attacks (e.g. terrorist attacks) that can severely impact workers, the population, the surrounding environment, and property. According to well established Security Vulnerability Assessment (SVA) and Security Risk Assessment (SRA) methodologies, the shooting threat to a chemical and process facility shall be investigated; however, the development of adequate damage models in case of shooting attacks using small/light weapons to industrial equipment units is still lacking. In the present study, an extended set of perforation models was retrieved from the literature and was validated against experimental data from perforation tests. The most reliable perforation models for soft core projectiles were selected and used to assess the vulnerability to perforation of atmospheric tanks storing hazardous materials for two reference projectiles enabling the identification of inherent safety threshold values for perforation thickness. [ABSTRACT FROM AUTHOR]

In the framework of design and installation of fire detection and fire alarm system in buildings, when high ceilings are involved, it is likely to run into the limits of the more common standards. Several regulations fix a ceiling height limit beyond which heat, smoke, and combustion gas detectors should not be mounted. Among the available technologies, the aspirating smoke detection (ASD) systems have the highest limit (i.e., 40 m according to BS 5839-1:2017). Nevertheless, this technology should not be used when processes that yield smoke, fumes, dust, etc., are present, and an alternative type of fire detector needs to be employed. This is due to the necessity to avoid false alarms, which is critical for successful fire detection and alarm systems. The concomitance of these two situations, i.e., dusty environments and high ceiling height, is not unusual in the industrial sectors. To investigate it, the state-of-the-art solution is adopting the principles of Fire Safety Engineering (FSE). The FSE is based on calculations that consider the conservation of mass and energy and permit to predict several crucial quantities such as the smoke temperature, smoke volume (and layer height), and species concentrations resulting from a fire of a given size (ISO/TS 13447:2013). In this work, a series of Computational Fluid Dynamics (CFD) simulations were conducted to assess the performances of a fire detection system composed of heat detectors installed at heights up to 20 m larger than the standard limit. The characteristics of an actual building adopted for storage of hazardous materials and a real heat detector system were considered. The temperature field resulting from two different types of t2-growth fire, i.e., one ultra-fast and one with slow evolution, were analyzed. The corresponding alarm times were evaluated and compared with ASD characteristics timings, recognized as a benchmark for its high sensitivity. [ABSTRACT FROM AUTHOR]

As widely acknowledged, learning from accidents represents one of the main source of knowledge for future loss prevention. An effective investigation may help enhancing the process of continuous improvement of the safety management system. Recently,, during a pipeline batching operation between two storage facilities of the same corporation, a LOC from the flange caused a spary release of atomised diesel, impacting on the adjacent national road. Two complementary approaches for accident investigation are here considered, i.e., customized root cause analysis workflow and Causal Analysis using System Theory approach. The best approach lies in the systemic nature of the selected methods applied to the whole socio-technical hierarchy of the concerned process trying to improve on one hand existing hazard analysis and on the other hand accident analysis. The paper outlines the fact-finding process from the technical viewpoint, as well as preconditions and latent failures. [ABSTRACT FROM AUTHOR]

The aim of the paper is to present Ammonia pressure station from the major accident prevention point of view. This object, located in the SEVESO establishment, present a significant source of risk which can cause serious consequences to human health and the environment in case of major accident. Ammonia, classified as a named dangerous substance, is stored in 500 kilograms pressure vessel, which is inside of the pressure station placed. The highest risk for surroundings presents transport of ammonia pressure vessel from the storage to the pressure station and transport to the storage naturally. For purposes of completion of approved SEVESO documentation, new risk assessment had to be processed. This paper focuses in particular on the possible negative impact on the environment in case of extraordinary release of ammonia from the pressure vessel. For calculation of consequence categories of the impact on the environment was selected methodology "Hazard & Vulnerability Index". The H&V index methodology is a Czech, official and frequently used methodology recommended especially for the environmental risk analysis in the SEVESO establishments. The benefit of this methodology is in its options to evaluate the impact to different parts of the environment, i.e. surface waters, underground waters, soil medium and biota considering diverse vulnerability of these components. Risk analysis via the H&V index methodology follows up on the determination of accident scenarios, a stage describing different transfer routes of ammonia release to the environment occurred in the establishment. The pressure vessel is to a steel pallet attached so that it can transported in the establishment by a forklift or truck. Four different places in the establishment was determined as the worst in terms of the environmental endanger (i.e. direct and indirect endanger of the environment, transport via sewer system etc.). Consequence categories were for closed surface water and biotic environmental compartments calculated. In conclusion, risk acceptability of determined scenarios is estimated in acceptable level. Results are presented via risk matrix recommended by H&V Index methodology. Visualization of scenarios is created by GIS. Proposed preventive measures including the way of liquidation of ammonia accidental release close this paper. [ABSTRACT FROM AUTHOR]

Chemical process industries are threatened with accidental and intentional adverse events because of the storage and operation of large quantities of hazardous substances. Safety and security barriers play important roles in protecting the chemical plants from safety and security-related undesired events and mitigating the potentially catastrophic consequences. Aiming to identify major accident scenarios in terms of both safety and security and determine the corresponding safety and security barriers, a novel approach based on MIMAH (methodology for identifying major accident hazards) and historical data analysis is proposed. In this approach, the MIMAH is extended to identify accident scenarios related to safety, physical security, and cyber security by using a combination of bow-tie analysis and attack tree analysis. Then, data analysis is conducted to supplement the identified major accident scenarios before the critical safety and security barriers can be identified and illustrated based on an integrated bow-tie and attack tree model. This study helps to identify major hazards considering both safety and security perspectives and supports the integrated assessment and management of safety and security barriers in the chemical process industries. [ABSTRACT FROM AUTHOR]

The possibility of inducing major accident scenarios by physical intentional attacks (e.g. terrorist attacks) to chemical and process plants processing and storing hazardous substances, has been increasingly recognized in the last decades. The identification of the credible security scenarios (chain from attack scenarios to major accident scenarios) is required by Security Vulnerability/Risk Assessment (SVA/SRA) methodologies, but an evident lack of supporting tools is present in the literature. The present study proposes a Bow-Tie approach for the identification of reference security scenarios to support hazard identification phase in SVA/SRA. The potential use of the results is demonstrated on a test case (industrial atmospheric tank storing a flammable liquid). [ABSTRACT FROM AUTHOR]

Wildfires approaching the Wildland-Industrial Interfaces can be a serious threat for industrial items located at the plant boundary. These items are typically storage tanks involving large amounts of hazardous substances. Ensuring their integrity is of paramount importance to prevent the wildfire spread inside the industrial plant, avoiding the occurrence of major accidents such as fires, explosions and toxic releases. A methodology for the evaluation of safety distances between tanks and vegetation for the protection from wildfire hazard was developed and applied to a case study. The outcomes provide useful information for an effective emergency response planning in the case of wildfire. Moreover, the results obtained rise concern about the appropriateness of clearance areas between the vegetation and industrial areas currently adopted. [ABSTRACT FROM AUTHOR]