Healthcare. Ref: Final results of the quench line inspection at your MAGNETOM system. Dear Siemens MR User,

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1 Ref: Final results of the quench line inspection at your MAGNETOM system Dear Siemens MR User, You received a letter from Siemens last December notifying you that quench lines for some superconducting magnets may not have been properly installed. Per your request, Siemens conducted a site inspection to assess whether the quench line for your MR system was installed in a manner that ensures safe operation. This letter is to inform you that Siemens site inspection identified minor deficiencies regarding the construction of the quench line at your site. What was found and what is the potential risk? The installation of the quench line connected to your Siemens MAGNETOM system was checked with respect to the parts of the quench line that were accessible to the Siemens Service Technician. At the time of your system assessment, the Siemens Technician inspected the quench line layout and it was determined that it is not in line with the quench line design document which is part of the Siemens Planning Guide. This failure to adhere to Siemens requirements presents a potential safety risk requiring correction. Attached to this letter is a detailed description of the deficiencies found, the potential risk(s) associated with these deficiencies and recommendations for corrections. How to avoid safety risk? In order to avoid severe safety hazards in the event of a quench, we urge you to have the corrections implemented immediately. Please contact your quench line manufacturer to remedy these deviations using the attached list and the requirements stipulated in the quench line design document which is part of the Siemens Planning Guide. Please recall, as noted in our earlier letter, that the Hospital/system owner is responsible for installing the quench line per the requirements defined and provided by Siemens. These requirements must be taken into account for any modifications implemented or planned after your system assessment. If you cannot locate the above-referenced documents, please feel free to contact our Customer Care Center at to obtain replacement documentation. Sincerely, Jerry Howze Director, MR Service Support Siemens Healthcare Hans Beinke VP, Quality & Technology Siemens Healthcare Siemens Medical Solutions USA, Inc. 51 Valley Stream Parkway Malvern, PA USA Tel.:

2 List of recommendations System type: MAGNETOM Sonata Serial Number: Functional Location: Site: UCLA MEDICAL PLAZA Recommendations Warning sign is missing People must be warned of the hazards by the outlet. There is a risk of cold burns and asphyxiation. It is recommended to fit a warning sign directly next to the outlet. The sign must have warnings both in English and the country specific language. If the outlet is lower than 5 meters, an additional warning sign could be fitted at eye-level below the outlet. Mesh inside outlet could not be verified due to missing information or cannot be accessed. Therefore the mesh cannot be verified as acceptable. Requirement: 10mm square with 1mm round wire, stainless steel. We cannot guarantee that the mesh of your system is within specification or even it is fitted. Page 1 of 1

3 Instructions when working on MR quench line outlets with a magnet at field This document provides steps on how to work on a quench line outlet safely. The requirements below help to mitigate the potential for a quench and impact of a quench while working on the quench Line. Information regarding magnet quenches, the effects of a magnet quench and what to do if a quench occurs have been included with these instructions. As only properly educated personnel should implement remedial work on any MR system quench line, this information must be communicated to the project manager, contractor or technicians prior to working on the quench line outlets. Caution: The magnet stays at field even when the system is powered off. Do not perform work during a period of precipitation (e.g. rain, snow). It is mandatory to follow these steps when working on quench lines. Ramping down the magnet. It is mandatory that the magnet is ramped down before any work is performed if the quench line outlet: Is located inside a building. Is surrounded on all sides by retaining walls. Is located in a confined area that does not offer easy egress/ exit. Is located in a public area that cannot be cordoned off to the distance described in the planning guide. Requires work in sections between the magnet and the outlet. Steps to mitigate risk to personnel before working on the quench line outlet. The following instructions must be followed to mitigate the risk to personnel in the event a quench occurs. Prior to working on the quench line outlets, the project manager, contractor or technicians performing the work must: Be aware and educated on magnet quenches, the effects of a magnet quench, and what to do if a quench occurs. Assess the magnet room for any potential risks (e.g., ensure the Helium level is not at or below the alarm level, etc.) Ensure that a minimum of two technicians are present while the work is being performed. Wear appropriate Personal Protective Equipment (PPE) at all times, including insulated gloves and safety glasses with side shields. If the work is being performed in an area where there is high risk of oxygen depletion if a quench occurs, PPE with oxygen supply should be used. Ensure the outlet is restrained properly during removal or replacement. Ensure all exits and escape routes remain accessible to personnel while working on the quench line outlet in the event a quench occurs. Ensure a deflector plate is not used to redirect any exhausted Helium gas to work areas in the event a quench occurs. Unrestricted Siemens Medical Solutions USA, Inc. 40 Liberty Blvd. MC: 65-1A Malvern, PA USA Tel.:

4 Ensure all work is performed from the side of the quench line outlet and not directly in front of the quench line outlet. Steps to mitigate risk while working on quench lines. The following instructions must be followed to mitigate the risk of a quench while working on the quench line outlet. Do not block the quench line outlet at any time. Do not use vibrating or grinding machinery on or near the quench line outlet. Do not weld the quench line outlet while it is connected to a magnet at field. Do not use or generate high voltages near the quench line outlet. The magnet and service room must be empty while working on the quench line outlet to mitigate the risk of inadvertently activating the Emergency Rundown Switch Unit (ERDU) or triggering a quench. No MRI scanning should be performed during the remedial work. This includes MRI scanning on a magnet that has a secondary quench line outlet near the one undergoing remedial work. Remedial work should not be performed during a power outage or if there is a water flow failure to the magnet system or if the Helium level is at or below the alarm level. We advise that you notify anyone at your organization that should be aware of this information. If you have questions about the content of this document please contact Siemens at Unrestricted Siemens Medical Solutions USA, Inc. 40 Liberty Blvd. MC: 65-1A Malvern, PA USA Tel.:

5 Working Safely with Magnets and Quench Lines- Safety Guide

6 Working on Quench Lines

7 Helium Gas Venting Risk A magnet quench releases up to 900,000 cubic litres of gas to atmosphere (31783 cubic feet). Gas flow from outlet is up to 922 km/h (572 m/h). Helium temperature -269 o C (-452 F). Expansion rate from liquid to gas of 723:1 1. Oxygen deficiency leading to asphyxiation OR lower levels leading to impaired judgement. 2. Cryogenic burns and hypothermia from contact with cold vented gas cloud, damage to lungs, damage to eyes. 3. Impaired visibility due to the gas cloud, leading to an accident. 4. Damage to buildings and equipment from cold gas venting. 5. Severe risk of burns in first 1-2 m (3.5 7 feet) of the gas jet from an outlet.

8 Safety - Gas Cloud Area Vertical outlets (Generally on roof tops). Outlet Option 1.5 T System 3.0 T System X (m / ft) Y (m / ft) X (m / ft) Y (m / ft) Vertical option 1 20m (65 ft) N/A 25m (82 ft) NA

9 Safety - Gas Cloud Area Horizontal option 1 & 3 Horizontal option 2 Horizontal option 4 Outlet Option 1.5 T System 3.0 T System X (m / ft) Y (m / ft) X (m / ft) Y (m / ft) Horizontal option 1 4m (13 ft) 4m (13 ft) 5m (16 ft) 5m (16 ft) Horizontal option 2 10m (32 ft) 3m (10 ft) 13m (42 ft) 3m (10 ft) Horizontal option 3 4m (13 ft) 4m (13 ft) 5m (16 ft) 5m (16 ft) Horizontal option 4 12m (39 ft) 3m (10 ft) 15m (39 ft) 3m (10 ft)

10 Safety Working on Quench Line Outlets Work on outlet (1) if there is no conflict with the gas area from outlet (2). Magnet 2 can operate / scan as normal. Conflict between the gas areas from outlet (1 and 2). Both magnets must stop scanning. No person inside the RF rooms.

11 Signature: