by Panos Charitos. Published: 27 May 2014

Fernando Pedrosa, ALICE GLIMOS, organized a visit to the new mock-up tunnel at Prevessin for the ALICE management team. Gilles Colin and the Fire Brigade teamed up with Christoph Balle and his colleagues from the Occupational Health, Safety and Environmental Protection Unit (HSE) to build it. The mock-up tunnel is the first step towards constructing a new safety training centre in the site.

Christoph Balle had worked for more than 20 years in cryogenics at the CERN Technology Department (TE) before becoming CERN's Safety Training manager at the HSE Unit. Christoph had developed an interest in safety issues and, when the LHC project moved successfully to beam operation, he decided to get more involved. Gilles Colin came to CERN as a professional fire fighter in 1980 and, in 2003, he began training the fire fighters. Since 2011, he collaborates with HSE for the safety courses and he is responsible for the training centre. “It is important to do the training, theoretical and practical, at one place,” he says.

Why was it important to build a new mock-up tunnel? In the past, one single shipping container was used to simulate the LHC tunnel. However, it was very dirty and full of smoke. Another problem was that only one type of exercise could be organized. Moreover, there was no proper space to recondition the training masks in order to use them for the next training-class. Christoph notes: “This was done in an old garage and the technicians had to work under bad weather conditions and with poor means in dealing with the chemicals that are used in this process”.

Installing dummy dipoles at the LHC tunnel mock-up. Image: Christoph Balle


Gilles adds: “Since 2005, we were concerned that in an accident of a helium leak in the LHC tunnel we would have to deal with the risk of oxygen deficiency.” He collaborated with his colleagues from the HSE Unit and TSOs to come up with a way to effectively train people working in underground facilities. They thought of building a safety training centre that would provide the necessary space for theoretical and practical training and would include a mock-up of the LHC tunnel. The unfortunate incident in 2008 underscored the importance of safety and the need for proper training.

The first shipping containers and modular classroom arrived at the beginning of 2013 and the mock-up tunnel was built in April 2013. Currently, a set of different exercises is available, including some of the most extreme scenarios that one could encounter in the tunnel; from a simple evacuation alarm to more complicated situations that can arise during the LHC run. The exercises could also help the trainees discern the different alarms; although the tonality is mentioned in the theoretical courses, one learns better by experience. Christoph continues: “In the mock up tunnel we also have the ability to train the people handling towing tractors. Finally, we have installed a biometric system similar to the one that everyone has to pass in order to get to one of the experimental areas. Thousands of users can benefit from this and get used to the procedure that they will have to follow or learn how they should deal with carrying radioactive materials.”

A number of different situations that may arise in the LHC tunnel can be simulated in the new LHC mock-up.

Fireman Gilles COLIN explaining the ODH (Oxygen Deficiency Hazard) alarm. Image: Christoph Balle


During the OpenDays 2013, the mock-up tunnel opened to the public. Gilles says: “It was a big success. Families with their kids – even children under 16, who do not have access to the tunnel– got a clear impression of the dimensions of the LHC and participated in some of the exercises that we had organized that day”. Christoph adds: “It was a very nice experience that helped us emphasize the importance of safety, not only at CERN, but more generally in people’s working environments and daily lives.”

Visitors queuing during OpenDays 2013 in front of the mock-up tunnel's entrance. A real biometric control door identical to those used to access the LHC tunnel has been installed thanks to ALICE generous support.

In the future, they would like to have a real safety training centre, where all related classrooms and hands-on facilities are housed next to the tunnel mock-up tunnel. It could be used, not only by newcomers or members of staff, but also by those working with certain contractors for a limited amount of time. Christoph notes: “Currently, on the induction day there is a short 15 min introduction on safety. In my opinion, this is not enough and, given that people are still trying to settle in at CERN, they often do not pay close attention to this course. We would like to invite them during the second or third week for a short training that would combine practical and theoretical aspects of safety.”

CERN has very high safety standards and Christoph notes: “Colleagues from other laboratories are often impressed by the work done at CERN. Of course, there is always room for improvements in safety issues and the HSE unit is constantly working towards this direction.“