CERN retention basin
An example of CERN’s water management strategy is the construction in 2020 of a retention basin near the Prévessin site. The basin will retain and, under certain conditions, regulate water from rainfall flowing off the Prévessin site into the Lion in order to retain incidental pollutants. (Image: CERN)


"I believe CERN should become a role model for an environmentally aware scientific laboratory."
  – Fabiola Gianotti, Director-General of CERN


Diagram of the 11 environmental domains at CERN
CERN follows up on 11 environmental domains to mitigate and limit the impact of our activities on the environment.

Over the decades, CERN has become a byword for excellence in research, establishing itself as a model for scientific collaboration across borders, technological innovation, training and education.

Today, environmental responsibility joins this list. Good environmental stewardship stands prominently among the Management’s objectives and is embedded in every corner of the Organization, with a strategic, proactive approach across the Laboratory and among CERN’s worldwide scientific community.

Contributing to the achievement of several of the environment-related UN Sustainable Development Goals (SDGs) is a natural continuum in this context, for example by improving our performance, forging partnerships with others and developing innovative solutions using CERN technologies.

Driven by this commitment to environmentally responsible research, CERN has implemented many initiatives over the years that have helped to reduce the impact of its activities on the environment. This page provides more information on these activities across different thematic areas.

CERN is fully committed to environmental protection and transparent reporting. CERN's public environment reports set out reporting frameworks, setting and monitoring concrete goals for constant improvement.


CERN and the environment (Video: CERN)


In Brief

During the period covered by the latest environment report, 2021-2022, CERN saw the completion of the second long shutdown and the restart of the accelerator complex (Run 3) with a view to reaching the new collision energy of 13.6 TeV at the Large Hadron Collider (LHC). In some domains environmental indicators may be very different during shutdown years compared to operation years, so they are shown for both years to highlight this, where relevant.



1215 GWh

In 2021 and 2022, CERN consumed 991 and 1215 GWh of electricity and 67 and 51 GWh of energy generated from fossil fuels respectively.

The Laboratory is committed to increasing energy reuse and to limiting rises in electricity consumption to 5% up to the end of Run 3 (baseline year: 2018), while delivering significantly increased performance of its facilities.


184 173 tCO2e

In 2021 and 2022, CERN’s direct greenhouse gas emissions (scope 1) were 123 174 and 184 173 tonnes of CO2 equivalent (tCO2e) respectively. Indirect emissions arising from electricity consumption (scope 2) were 56 382 and 63 161 tCO2e. In addition, indirect emissions from business travel, personnel commuting, catering, waste treatment and water purification (scope 3) amounted to 7813 and 8956 tCO2e. Emissions arising from procurement (scope 3), which are reported for the first time, amounted to 98 030 and 104 974 tCO2e.

CERN’s objective is to reduce direct emissions by 28% by the end of Run 3 (baseline year: 2018).


3300 ML

In 2021 and 2022, CERN used 2661 and 3234 megalitres of water respectively.

The Laboratory is committed to keeping its increase in water consumption below 5% up to the end of Run 3 (baseline year: 2018), despite a growing demand for water cooling at the upgraded facilities.


< 0.01 mSv

In 2021 and 2022, the actual dose received by any member of the public living near the Laboratory was less than 0.01 mSv , which is more than 100 times lower than the average annual dose received from medical exposure per person in Switzerland.

CERN is committed to keeping its contribution to no more than 0.3 mSv per year.


69% recycled

In 2021 and 2022 respectively, CERN disposed of 5111 and 8812 tonnes of non-hazardous waste, and of 1544 and 1295 tonnes of hazardous waste, including 307 and 519 tonnes of radioactive waste. The recycling rate rose from 56% (baseline year: 2018) to 69%.

CERN’s objective is to increase its recycling rate for non-hazardous waste.


45 dBA at night

In 2021 and 2022, average noise levels measured on the boundaries of CERN’s sites are typically around 50 dBA during the day and 45 dBA at night. CERN implemented measures to improve its noise management, including the installation of an online real-time monitoring system.

CERN is committed to restricting noise at its site perimeters to 70 dBA during the day and 60 dBA at night.


18 species of orchids

In 2022, a new species of orchid was discovered on CERN’s sites, bringing the total to 18 species, as well as 62 species of Lepidoptera and 32 species of Orthoptera.

Knowledge transfer

8 environmental projects

In 2022, CERN launched the Innovation Programme on Environmental Applications (CIPEA) and eight projects were selected for implementation with the financial support of external partners or the Knowledge Transfer fund.

CIPEA spans four focus areas where CERN’s know-how can be of use, namely renewable and low-carbon energy; clean transportation and future mobility; climate change and pollution control; and sustainability and green science.


Continue for more information on CERN's environment reports

Biennial reports

Environmental domains at CERN

Conserving biodiversity
Minimising atmospheric emissions
Monitoring water releases
Limiting soil pollution
Reducing noise emissions
Improving energy efficiency
Managing waste centrally
Optimising risk management
Monitoring and minimising exposure
Managing and mitigating
Preventing incidents proactively