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Environmental awareness: An environmental perspective on managing hazardous liquids

How are hazardous liquids managed at CERN, and what are the consequences for the environment?

Hazardous substances
Safe delivery of a chemical agent in a dedicated unloading/loading area: area under retention, delivery procedure in place, spill kit readily available (Image: CERN)

CERN uses various hazardous chemicals for carrying out a range of activities, both industrial and experimental. These chemicals include cleaning products, substances for treating accelerator equipment, polymers, various petroleum-derived products, organic fluids and corrosive and toxic liquids. These chemicals are used in a wide range of applications, such as for electrical insulation, lubrication for machining metallic or non-metallic materials in workshops, and fuel for electrical generators.

If accidentally released, these liquids will have a serious impact on the environment, in particular on aquatic fauna. CERN is surrounded by low-flow watercourses, which are very sensitive to even minor releases. Non-toxic substances, like organic oils, can also cause serious damage by reducing the oxygenation of a watercourse. All chemicals therefore need to be carefully managed.

In line with general prevention principles, the use of hazardous chemicals must be avoided where possible. For example, mechanical cleaning should be favoured over cleaning using solvents. When it cannot be avoided, the least hazardous chemical should be selected. The activities concerned should be regularly reviewed in the light of these prevention principles.

When using hazardous liquids, various protection measures should be implemented during handling and storage, such as retention basins, spill kits for managing leaks, and clear and understandable labelling. Personnel working with chemical agents must be properly trained and familiar with safety procedures to ensure that hazardous liquids are used safely.

Finally, all chemicals (gas, solid and liquid) must be registered in the Chemical Register for Environment, Health and Safety (CERES). This centralised database provides the appropriate CERN services with all the relevant safety information. It includes both chemical and environmental risk assessment methods and presents the evolution of the risk score over the years.

CERN experts are available to support the identification and evaluation of hazardous substances and to propose mitigation measures.

An e-learning course is also available if you want to learn more about chemical safety at CERN.

For further questions, please contact Env-Prevention@cern.ch.


This article is part of the series “CERN’s Year of Environmental Awareness”.