MPGDCAL (ID: 1319)
ISIEC – Initial Safety information on Experiments at CERN
Date: Tuesday, July 9, 2024 - 14:58
This document shall be completed by the Experiment Safety Contact of an experimental collaboration, whenever it intends to bring new experimental apparatus, new test beams or make major modifications to experimental apparatus already operating at CERN.
The purpose of this document is to provide a summary description of the equipment that is to be brought to CERN and the activities that are to be carried out. This document will then allow the EP Safety Office (EP-SO) to perform an initial safety assessment; i.e. identification of the applicable safety requirements, control measures, etc.
This ISIEC document will serve as a basis for the safety information on an experiment. Further documentation may be requested to improve the understanding of safety hazards.
- Recommendations and procedures will follow after the provision of this document. Note that if the experiment is considered to have major safety implications then the CERN HSE unit will become involved and their safety procedures will then be followed.
- A Launch Safety Discussion may be called for by the EP-SO. This will take place on site with representatives of the experiment, EP-SO, the HSE Unit and other CERN Departments.
- A formal ‘Safety Clearance’ of the experiment must be given prior to the experiment being allowed to start operating (for example to receive beam).
Please note that this form must be completed and sent to CERN prior to the arrival of the planned experiment. Work will not be allowed to start until this form, and any requested complementary information on safety hazards, has been completed and handed over as explained above.
The EP Safety Office is available during normal CERN working hours for test beam safety inspections (i.e. Monday to Friday between 8 am – 6 pm)
Note: For EP safety clearance visits in EHN1, there is a block of time each week between 15:00 and 17:00 every Wednesday to speed up the clearance process. Ideally, we will schedule all EHN1 safety clearance visits within this time window.
There may be exceptions when an earlier/later inspection of your setup is required for technical reasons. If your installation in EHN1 will not be available for a safety clearance in the preferred window, please request a date/time when your setup will be complete and we will contact you to confirm the inspection schedule.
micromegas detectors and 5 μRWELL detectors are hosted together with a GEM detector, the latter used for MIP identification.
A third structure, called "Rhum", will be also placed after the calo structure to check for multiple tracks with 2 50x50cm2 micromegas chambers.
After an initial period where the chambers response to the pion beam will be tested, iron slabs of dimensions
20x20x2 cm3 will be placed inside the calo structure and between the detectors, to realize a hadronic calorimeter prototype.
All the 20x20cm2 micromegas chambers will run under Ar:CO2:iC4H10 (93:5:2) which is non-flammable, while all the μRWELL chambers will run under Ar:CO2:CF4 (45:15:40). Instead the 2 50x50cm2 chambers will be operated with Ar:CF4:Iso (88:10:2). The nominal flow for all mixtures will be ~2 l/h; the estimated consumption of CF4 is 0.9 kg.
-High voltage: HV power supply to power detectors - up to 5kV, less than 1 mA - all
under tripping control in case of over-currents
Rhum structure will be placed behind the calo structure directly with crane, after the installation of the desy table.
Roles and Responsabilities
In accordance with its intergovernmental status, the Organization establishes and updates Safety Rules to implement its Safety Policy.
For definitions please refer to the Safety Regulation SR-SO “Responsibilities and Organisational Structure in Matters of Safety at CERN”.
Safety Clearance
The procedure for the safety clearance will depend on the type and duration of the experiment and whether or not there are major safety implications. In all cases a formal safety clearance is a requirement before an experiment can start operating