Safety risks – Road Safety

Thousands of us use the CERN roads every day. With the variety of modes of transport, with motorbikes, (e-)bicyles and (e-)scooters joining cars and pedestrians on the network, we all have a role to play in keeping ourselves and each other safe.

When using roads, inside and outside CERN, common sense and common courtesy prevail. Look out for other road users, and for yourself! 

It’s not only Safety first. It’s Safety always.

In case of emergency or incident, call the CERN Fire & Rescue Service on +41 22 76 74444.



Regulatory framework

Everybody must respect the rules of the French and Swiss highway code on site, in the same way as outside CERN.

In particular, everyone using the road must moderate their speed, respect pedestrian and cycle paths and be mindful of other users at junctions and crossings.

Mind your speed!

Speed limit


The general speed limit on the CERN sites is 50 km/h, and pedagogical speed radars are deployed in the most accident-prone areas of the domain.

Please be aware of certain areas were the speed limit is 30 km/h, clearly signposted as such.


In 2022 and 2023, 187 road safety incidents were reported on the CERN sites. Of these, 84 involved bicycles. This number is probably greater in reality as not all incidents are reported. Whether you are a victim or a witness, it is very important to report any event (see below).


cycle stats

The analysis of traffic incidents shows that the most common causes are lack of attention or lack of respect for other road users. Did you know that among the 84 cycling events, 34 incidents were linked to vehicles not giving way?

Common sense and mutual respect, vigilance and paying attention (no mobile phones whatever the mode of transport!), as well as exercising greater caution towards the most vulnerable users, are the cornerstones of road safety.

Reporting accidents and incidents or near-misses: don't hesitate!
Reporting accidents are vital for the continued improvement of CERN's campus in terms of mobility and road safety. 
If you are the victim or witness of an accident or near-miss, inside or outside the CERN site, report it promptly using the Incident Declaration Form (EDH).

Infrastructure and mobility services

The Site & Civil Engineering Department (SCE) is responsible for CERN's road infrastructure and mobility. Any issues with the roads or paved areas, such as repairs of potholes and pavements, and markings and signage, can be addressed to the Roads service.  

The Organization has a dedicated Mobility Working Group comprising representatives of all Departments, including the HSE Unit. The group regularly reviews road infrastructure matters and recommends measures to improve all aspects of mobility at CERN, including safety. These include how to improve traffic flow, develop cycle lanes and footpaths, and ensure an optimized infrastructure for the benefit of all users, whatever their mode of transport.

 ==> Find out more about the extensive mobility services on offer on the SCE Mobility services website

An increasing number of car park spaces are designed for reverse parking to avoid accidents and keep traffic flowing safely. Reversing out of a parking space can be dangerous, especially when it’s onto a busy road or into a cycle path.

In the event of a site evacuation, vehicles must exit the CERN domain rapidly. Reverse parking is therefore strongly recommended wherever possible for safety reasons. These sign below indicate where reverse parking is compulsory.

Reverse parking



Courses: Safety and general

CERN offers an e-learning module on Bike Safety, which is available on the CERN Learning Hub. The course covers all important aspects including road safety rules, equipment and care of one's bicycle as well as safety tips. It is mandatory for anyone wanting to rent a CERN-(e)bike.

If you wish to follow a general course to improve your cycling skills, ProVelo in Geneva offers a variety of courses that you can find on this link.

Bike equipment

NOTE: the figure shows the minimum equipment you'll need for your safety on your bicycle: please refer to the mandatory/recommended bicycle equipment in France and in Switzerland (links in French)

Mandatory bike equipment


"Hot spots": two key areas to be particular careful of on the CERN site

Entrance B: bicycles have a separate lane, but be careful and mindful of cars wanting to turn right in the direction of Geneva!


Entrance E: here there is heavy traffic at peak times. Vehicles may cross the cycle lane without due care and attention: ensure you may eye contact with drivers for a safe onward journey!