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A reminder of the COVID-19 measures in place


Benoît Delille is the head of the HSE Unit

Our capacity to tackle COVID-19 depends on the efforts of everyone

As the summer holidays come to an end and school classes resume, it’s a good time to remind ourselves of the measures in place to protect us all from COVID-19. Huge progress has been made since the pandemic began, allowing measures to be relaxed to some extent, in a way that recognises that the virus that is still with us.

CERN’s approach to handling the pandemic has been, unsurprisingly, driven by science. The range of measures we have applied from the start has been very diverse and based on the evidence available at the time. We’ve continuously monitored the facts, and adjusted our measures accordingly. For much of the pandemic, CERN’s measures have been stricter than those of the Host States, and when we have relaxed them, we have done so only after a thorough analysis of the prevailing conditions in the region, or because the growing body of epidemiological evidence has allowed us to do so. For example, when studies appeared indicating that distancing of 1.5 metres is as safe as 2 metres, we relaxed that requirement.

In parallel to the application of now well-known measures, we’ve developed tools, like CARA, that help us to assess the level of risk in shared spaces, and apply appropriate preventative measures. CARA has also raised much interest outside CERN, and its use has been deployed by other organisations. CARA has contributed to a number of academic papers, and allowed CERN to be part of a working group convened by the WHO with the aim of developing an algorithm and methodology to quantify airborne risk transmission. We are also trialling the use of CO2 monitors as a means to verify the quality and renewal of air, and to help substantiate the results of the CARA tool.

This summer we moved our COVID level to 2 – Yellow, allowing people to come back on site. Throughout the summer, the overall number of people coming on site has remained stable at around 4500 people per day, just slightly higher than when CERN was at level 3 – Orange. Throughout this period, the positivity rate has remained low among the CERN community, and in line with the rate in the local region. Many of those coming back on site were grateful of the opportunity to see colleagues in the flesh, instead of on zoom. For those who are vulnerable or are uncomfortable about coming on site, flexibility has been the key word, along with specific protection plans where appropriate.

Many of us, naturally, keep a close eye on the incidence rate. It is an important factor in determining which level CERN applies, but it is just one factor out of many. We have also taken into account factors including the conditions applying in the Host States, the strong evidence concerning the impact of vaccination programmes, the spread of new variants, the capacity of the site and the desire of many to come back on site under safe conditions.

Our approach going forward is to acknowledge that the virus will be with us for some considerable time, and to keep CERN as open as possible in this new normality while maintaining strict measures to safeguard everyone’s health. For that reason, we strongly encourage vaccination, coupled with regular testing provided free of charge to everyone on site, the application of health and safety measures and the mandatory use of Proximeters while on site. This approach allows us to keep coming on site, and to prevent spread by identifying those carrying the virus, and those they have been in contact with.

Keeping the community informed through the regular COVID-19 emails is an important part of CERN’s approach. These mails not only include information necessary for us all to carry out our work, and live our daily lives in both Host States, but also links to some of the studies that guide our actions as the situation and our knowledge of the virus evolve. Success relies on everyone making an effort: read the regular COVID-19 emails carefully, get vaccinated if you can, if you are coming on site, test regularly, respect the measures in place, and do not come on site if you have even the most minor symptoms. We are all looking forward to a return to normality, although things will never be quite as they were before, and it requires all of us to get there.