SAFETY FOLLOW-UP HL-LHC PROJECT WP17 – Infrastructures meeting S. La Mendola, Jose Gascon DGS/SEE 09 July 2015

RF System – HV converters (TE-EPC): capacitors at 10kV (no liquid insulation) or 40kV (oil insulation) – Control racks: PLC, cables, PCBs, etc. - classical combustible material – Tetrodes: no identified combustible Power Converters – No oil insulation – Use of small electro-chemical capacitors – Classical combustible materials: cables, PCBs and plastics for capacitors – Mainly copper and metallic component – All components will be in a metallic enclosure not tight – For capacitors some data will be sent to assess impact FIRE LOADS ASSESSMENT (Ongoing)

Electrical distribution – UPS Batteries – Heating Cables in X cable trays – Dry Transformers Cryogenics – Compressors??? – Control racks Cooling & ventilation – Fans, motors??? – Cables – Control racks FIRE LOADS ASSESSMENT (Ongoing)

Transport – Electrical motors??? – Batteries (special vehicles)?? – Control racks Others??? FIRE LOADS ASSESSMENT (Ongoing)

Burning of electronic cabinets and cable trays Main failure modes: 1.Overheating; 2.Short circuit and ground fault; 3.Arcing

Protection measures for cabinets Interior and exterior fire protection (for example according to DIN “Fire behaviour of building materials and building components”) Similar cabinet used for R2E project

Protection measures for cabinets Typically suppression systems are made up of either of the following suppression agents: CO 2 Foam Water Powder Etc. System already in place in ATLAS, ALICE, LHCb and CMS, using different control systems (5 kg bottles CO 2 ) for 52U standard racks. They are based on thermocable and smoke detection. See EDMS “Options for the use of the MiniMax System”

Protection measures for cable trays Tested against EN “Fire resistance tests for service installations Part 11: Fire protective systems for cable systems and associated components” Classified against EN , e.g. EI-S 120 (v e h o i↔o), where E = Integrity I = Insulation S = smoke leakage, less than 200 m 3 /(m 2 ∙h) 120 = duration of fire resistance in minutes

Smoke hazard characterization Literature review Calorimetric fire experiments on electronic cabinets, J. Mangs et Al. Characterization of closed-doors electrical cabinet fires in compartments, W. Plumecocq et Al. Characterization of the fire environments in central offices of the telecommunications industry, A. Tewardson Energy balance in a confined fire compartment to assess the heat release rate of an electrical cabinet fire, M. Coutin et Al. Risk analysis of the LHC underground area at CERN – Fire risk due to faulty electrical equipment, A. Harrison Modelling of electrical cabinet fires based on the CARMELA experimental program

Combustion of electronic cabinets Experimental apparatus, results and models Growth phase Decay phase

Fire Modelling Tools: Quick method to Calculate Fire Load of Cable Trays and Ladders. F. Corsanego DGS/SEE/XP, EDMS Fire Modelling Tools: Characterization of burning behaviour of a stack of horizontal cable trays – unconstrained fire F. Corsanego DGS/SEE/XP, EDMS Combustion of cable trays, available models

Simplified calculation of necessary smoke extraction flow rate Reference smoke extraction flow rate for the tunnel of m 3 /h. See for example Enclosure Fire Dynamics, Karlsson and Quintiere

Definition of smoke extraction concept with EN/CV Organization of the underground volumes in «smoke compartments». Extraction ducts dimensioned for one compartment (18000 m 3 /h). Natural fresh air intake from the access shaft (openings in surface building) Use of smoke curtains (EN ) to define the compartment limits. Use of fire rated smoke extraction ducts (EI-S 120 v e h o ) for multiple compartments (EN ). Higher smoke extraction flow rate for the cryo cavern. One additional smoke extraction duct.

Evacuation of occupants Evacuation of occupants can be simulated (e.g. agent based software, analytical calculations) taking into account the smoke dynamics (production, propagation, extraction) Tenability thresholds are established (visibility, temperature, etc.); t RSET < t ASET (ISO “Fire safety engineering – Evaluation of behavior and movement of people) RSET = Required Safe Egress Time ASET = Available Safe Egress Time

Possible ground for cooperation with universities Contact with Lund university established Possible collaborations in fire and evacuation modeling for HL-LHC

Questions?