2.  Market Survey  Design, supply, delivery and installation of a Clean Room Facility  at the entrance of the LAr detector tank,  used for the storage and preassembly of the LAr detector internal components.  The facility should also provide the air treatment of the LAr tank volume.

3. 16 x 10 m2, 5  Clean Room Buffer 16 x 10 m2, 5 meters high access  LAr tank access via the Clean Room Buffer  Access dimensions tbc (services via access doors)  10 persons  10 persons working in the area at the same time Clean Room Buffer LAr tank

4.  Air entering is filtered  Air entering is filtered to exclude dust, and the air inside is constantly recirculated through high-efficiency particulate air (HEPA) and/or ultra- low penetration air (ULPA) filters to remove internally generated contaminants. airlocks air shower stage  Staff enter and leave through airlocks (sometimes including an air shower stage), and wear protective clothing such as face masks, gloves, boots and coveralls.  Equipment inside the cleanroom is designed to generate minimal air contamination. Even specialized mops and buckets exist... Common materials such as paper, pencils, and fabrics are often excluded.  Positive pressure  Positive pressure so that air leaks out of the chamber instead of unfiltered air coming in. humidity to low levels  Some cleanroom HVAC systems control the humidity to low levels.

5.  ACCESS PROCEDURES special shoes  Low-level cleanrooms may only require special shoes, ones with completely smooth soles that do not track in dust or dirt. cleanroom suit  Entering a cleanroom usually requires wearing a cleanroom suit. gray room  In less rigorous cleanrooms (ISO 8), the entrance to the cleanroom may not have an air shower. There is an anteroom (known as a "gray room"), in which the special suits must be put on, but then a person can walk in directly to the room. do not use fully classified cleanrooms  Some facilities do not use fully classified cleanrooms, but use some cleanroom practices together to maintain their cleanliness requirements

6.  Overpressure 10 Pa  1400 m2, 12000 m3  1 MEuro  4 months work execution

7.  Clean Room Buffer and LAr tank: ISO 8 as per ISO 14644 standard (equivalent to CLASS 100000 as per US FED STD 209E standard);  Clean Room Buffer and LAr tank over pressurized ;  Clean Room Buffer : › dust free wall, ceiling and floor linings; › non static floor and/or electrically conductive; › high intensity lighting systems (tank?);  LAr tank access through the Clean Room Buffer.

8.  Standard principle for Clean Room ISO 8 type. 2000 kg/m2 working load  Most of the characteristics for the walls, ceiling/roof, floor have been defined (sealed meeting clean room standards, chlorine and alcohol free, PVC may also be proposed, floor 2000 kg/m2 working load, et.). lighting 2 tons overhead crane  Services: lighting and the 2 tons overhead crane LAr tank Clean Room Buffer

9.  Lateral air ducts supply air from the bottom  Lateral air ducts supply air from the bottom : space available to be defined in detail (supporting system, et.). cupola  Space available on top of the roof… under the cupola. temporary lighting Gas, 230V  Services: should we foresee a temporary lighting system for the tank ? What about the other services ( Gas, 230V, etc.)? Clean Room Buffer

10.  MS document 90% ready  Some technicalities to be defined  To be added: › Access procedures › Access procedures to the working area as per procedures adopted by the mine in Pyhäjärvi › Internal rules › Internal rules and procedures to be respected during interventions on the mine premises › Safety training › Safety training, internal documents, rules and procedures. All workers are required to pass and validate the mandatory safety courses… working areas › Dedicated working areas on the surface and underground

13. Class maximum particles/ft³ISO equivale nt ≥0.1 µm≥0.2 µm≥0.3 µm≥0.5 µm≥5 µm 135731 ISO 3 10350753010 ISO 4 100 750300100 ISO 5 1,000 7ISO 6 10,000 70ISO 7 100,000 700ISO 8