Vol 48 - Editorial
Over this more than 40 year period, there have been great advances in knowledge relating to process safety, but at the same time, plant complexity and economic pressures have also increased. In addition, innovations in technologies and societal developments are emerging, which will require further work for improvement in order to cope with these new challenges. Innovation is leading to new processes under yet unknown conditions and introducing potential new hazards from novel or emerging technologies, and materials.
Therefore there is a continuous need for further research and development to identify and manage the risks from these innovations.

This CET volume collects papers that fall into seven groups relating to seven major topic areas or themes.
THEME 1 - MANAGEMENT AND COMMUNICATION of Risk and Safety
Engagement with all stakeholders who might contribute to, or be affected by, the risk of a Major Accident is an integral part of the management and regulation of risks. Key aims of risk communication are to inform and advise people about risks they can control, to dissuade people from risky behavior and to enable effective participation in managing risks. This theme focuses on new approaches for the identification, management and communication of risks in the major hazard industries. A further focus relates to best practices for communicating safety and successful risk management to protect and engage the wider public.

THEME 2 - HUMAN AND ORGANIZATIONAL FACTORS
Experience has shown that serious accidents almost never result from a single cause. Human and organizational factors have significantly contributed to the causes of several recent incidents in a variety of industries with major accident hazards. In these incidents, management systems failed to effectively secure the barriers in place, and, since humans implement these management systems, humans are implicitly involved in some way. This theme covers all aspects of human and organizational failure, and especially to new or novel ways to understand and control these failures.

THEME 3 - LEARNING FROM ACCIDENTS AND KNOWLEDGE TRANSFER
Preserving knowledge and experience (good or bad) is essential in a highly dynamic business environment. This theme is therefore focused on systems and methods to capture, retain and store knowledge. It also covers the transfer of know-how to engineers, plant managers and operators "on the front line". This theme focusses on case histories and the analysis of actual incidents and accidents, both of which are important sources of experience. In addition the theme addresses methods for systematic incident investigation and derivation and the communication of lessons learned.

THEME 4 - FIRES AND EXPLOSIONS
Fires and explosions still cause the highest amount of physical damage in the process industries, meriting a separate theme dedicated solely to this threat. The theme covers all topics related to preventing and mitigating fire and explosion damage. Topics cover fire and explosion resistant design of plants and buildings, ex-zoning, fire and gas detection, alarm and mitigation systems, and relief systems. This theme also covers the important topic of elimination of ignition sources, addressing areas such as static electricity; the identification of hazardous materials; and the safety assessment of chemical reactions (e.g. runaway reactions, self-ignition).

THEME 5 - SIMULATION AND MODELING
The calculation capacity at hand in a normal PC or Laptop has extended the accessibility of simulation and modeling software to a much wider range of users. Understanding the underlying models and their limitations is a critical step to judge the reliability and applicability of the results obtained. This theme focuses on the capacity to use desktop methods to simulate and model situations which are difficult to reproduce due to their scale or hazard level. It also addresses the practical application of such tools. Modeling or simulation of source terms; the dispersion of hazardous materials; fire and explosion; or of any other process safety related modeling including the prediction of hazardous properties, will fall within in this theme.

THEME 6 - PROCESS SAFETY ENGINEERING
Process Safety Engineering (PSE) focuses on safety issues in the design phase of industrial process facilities, but is not limited to it. PSE examines the reduction, suppression and elimination of hazards from manufacturing processes, with specific attention on inherent safety and successful engineering practices. Potential solutions include: next to design-based safety; add-on safety features; safety instrumented functions and safety integrity levels; layer of protection analysis; resilience for process safety; and related topics. Contributions deal with innovative developments in safety aspects of plants and products and new approaches in process engineering design.

THEME 7 - REGULATORY ISSUES
Regulatory issues in process safety and loss prevention are dominated within the European Union by the Seveso Directives, of which the Seveso III Directive is required to be implemented in national legislation by 31st May 2015. However this only describes a framework for the control of major accident hazards in onshore operations. Many more specific regulations exist, covering such topics as: classification of hazardous substances; definition of explosive atmospheres; design and operation of particular types of installation (e.g. LPG storage, tank storage of flammable liquids); as well as offshore oil and gas operations. Theme 7 "Regulatory Issues" seeks to address questions related to the development and practical application of process safety related regulations. This should include not only the legal aspects, but also mechanisms and tools for achieving effective compliance.

Exchanging information, disseminating data and stimulating the development of new methods to reduce the risk of incidents/accidents in the process industries, is a must and a need.
We are convinced that this Volume dedicated to Loss will provide the opportunity to learn and exchange best practices, to transfer experience, learn from case studies, and to preserve existing know-how for the benefit of the process industry and the safety of employees and the public.
Eddy De Rademaeker, Peter Schmelzer (Guest Editors)