[en] Mountain regions concentrate characteristics that make the effects of climate change particularly visible. They are therefore sentinels of ongoing and future changes and impacts. They have natural and socio-economic features that distinguish them, particularly in terms of water resources, biodiversity, agricultural and cultural heritage, including the specific high mountains environment, which supports emblematic leisure and tourism activities. They are also characterized by many natural gravitational hazards that complicate and increase the cost of their socio-economic development. Climate change affects almost all of these interconnected issues, modifies their characteristics, and undermines traditional management methods of these features and intrinsic difficulties. Interdisciplinary knowledge and tools are being developed to take this into account in territorial development strategies. (author)

[en] After a recall of some definitions (extreme events, risks related to extreme events) and a discussion of the way extreme meteorological events are addressed by social sciences, this publication proposes an overview of extreme climatic events which occurred in the past and are occurring now by addressing observations, human and financial costs. It also outlines the relationship between already observed changes and human activities. Then, it discusses the future impact of climate change on major natural risks. The next part addresses the prevention and management of risks related to extreme climatic events (issues of adaptation, of mobilisation of all actors, of a structured and long-term policy which articulated additional actions, examples of implementation of measures to reduce vulnerability and exposure to risks). The document also contains the activity report of the ONERC (the French national observatory of effects of global warming)

[en] The contributions to this colloquium on the issues related to optical and electromagnetic radiations on the workplace address various aspects: effects on health and regulation (exposure to artificial optical radiation sources, effects of UV, visible and IR radiations on skin, UV, blue light and phototoxicity, application regulation to prevent risks of exposure to artificial optical radiations, applicable safety standards, retinal toxicity of blue light, industrial electromagnetic radiation sources, assessment of human body exposure to non-ionising electromagnetic fields, transposition of a directive), assessment and prevention (risk assessment without measurement, measurement of non-coherent optical radiations, risk assessment for Led luminaries, preventive and protective means, protection equipment against Led-related risks, organisation of laser-related risk in the CNRS, electromagnetic field measurement and measurement uncertainty, metrology of low-frequency pulsed fields, exposure assessment for EDF workers, an intervention protocol for simplified risk assessment, a simple tool for a first assessment of exposure to electromagnetic fields, medical survey of workers, means of prevention against electromagnetic fields), and case studies (scene spotlights, IR-based radiating drying systems, furnace slags, laser safety in medical environment, magneto-scopy control, high frequency welding press, electric fields measurements and preventive actions in telecommunication systems, exposure due to medical active implants, worker exposure in MRI environment)