SNS ELECTRICAL SAFETY WORKSHOP 2004

1. SNS ELECTRICAL SAFETY WORKSHOP 2004 1 SNS Electrical Safety Workshop

2. SNS site primary AC description • SNS site grounding • SNS site secondary AC distribution • SNS site DC and Instrumentation distribution and Installation • SNS Electrical Safety Committee SNS Electrical Safety Workshop

3. Tennessee Valley Authority TVA supplies power via 161kV lines to TVA HV switch yard • Two TVA 161/13.8kV 45MVA transformers supply SNS 13.8kV main switch house, which has a 13.8kV switchgear with bus A and bus B. Bus A feeding KL, HE, RN, RT, TA, CL substations 13.8kV/480V and bus B feeding KL modulator substations 13.8kV/2.4kV. CHL is fed from bus A and B by a loop feeder. SNS Electrical Safety Workshop

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5. The entire facility grounding consists of 100'x100' mat of 4/0Cu wire exothermically welded. Each crossing is tied to a grounding rod. An additional grounding rod is added on building perimeter for lightning protection. (SNS grounding grid_) The facility has enhanced (low impedance) RF grounding for the klystron building at each klystron station. Owing the fact that the building lay out has not been finalized at the time of RF grounding being installed, the additional RF mat is terminated on the north wall of the klystron building to a grounding plate. (E7-01-02.PDF) Electrical distribution is grounded and bonded to the 100'x100' mat. 2/0Cu wire is run with cable tray system and along the beam line for grounding and bonding of equipment. In addition to 2/0 wire in the LINAC tunnel, grounding plates tied to the 100'x100' mat are embedded in the LINAC tunnel wall every 100'. Single point ground for beam diagnostic is provided on the north wall of the klystron building. Equipment racks, water carts, modulators, etc., will have AC service grounded and bonding and grounding of enclosures will be provided. Raceways will be bonded and grounded. Shielded cables will have the shields bonded and grounded at the equipment site (not at the beam line component side). • In addition, there are three ground breaks provided in the ring tunnel that separate HEBT and RTBT from RING service building and the ring tunnel itself has a ground break in the north collimator section. • The beam line components and supports are bonded and grounded (2/0Cu) SNS Electrical Safety Workshop

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8. Secondary Power Distribution Reliability and Safety • When designing any power system under the new Construction Design and Maintenance (CDM) regulations (OSHA, NEC) safety is an important factor. It is worth acknowledging that safety and reliability can conflict. This can happen when safety considerations require the introduction of additional complexity, such as the provision of safety interlocks, which reduces reliability. • Safety must always take precedence and additional steps will be required to maintain the required reliability. SNS Electrical Safety Workshop

9. Secondary AC distribution 480/208V to the accelerator equipment and facility equipment is strictly by NEC. • SNS project has chosen finger safe electrical equipment components to avoid interlocks for personal protection against accidental electrical contact for voltages above 50V or stored energy above 10J in the equipment racks. • Secondary AC distribution has also the accelerator equipment loads separated by equipment category and separate transformers are used to power magnet power supplies and beam line instrumentation. • Emphasis is given to grounding and bonding. Ground loop impedances are measured before installation is released for operation. SNS Electrical Safety Workshop

10. DC and instrumentation cabling for accelerator beam line components is selected and approved by a three member committee. Main criteria are intended use, NEC, fire and radiation. • Guidelines for accelerator beam line component cabling are written in the SNS document – SNS 109010200-DC0001-R02 Spallation Neutron Source Cabling Design Criteria. • List of approved cables on line with manufacturer specifications and applicable UL and IEC listings. SNS Electrical Safety Workshop

11. DESO&GESO SNS Electrical Safety Workshop

12. The organizational chart is according to Standards Based Management System (SBMS) adopted by ORNL in 2002 for All employees • Roles Responsibilities Accountabilities and Authorities (R2A2) define the relationship between the employee and the supervisor. R2A2 also defines how ORNL intends to manage itself. • R2A2 provides a template for training necessary for a employee to perform specific tasks. SNS Electrical Safety Workshop

13. Spallation Neutron Source Electrical Safety Committee Charter • PURPOSE: The Spallation Neutron Source (SNS) Electrical Safety Committee (ESC) is an internal review committee advisory to management regarding all issues related to occupational or environmental Electrical safety at the SNS. These issues include not only electrical safety for accelerator operations, but also compliance of electrical installations to NEC and OSHA 29CFR 1910 S. • Specifically, its duties are to: • Develop, review and update facility-specific policies that implement the ORNL Electrical Safety program, the Non Reactor Nuclear Facility Safety (DOE Order G-420.1-1), where applicable, enforce NEC and OSHA 29CFR 1910 S. • Provide continuing assessment of facility compliance with ORNL requirements, DOE Order G-420.1-1, and the approved safety documentation (Safety Assessment Document and Safety Analysis Report) for the SNS. At a minimum, the committee will assess facility Electrical Safety before the startup of major SNS activities and review operating experience on a routine basis. SNS Electrical Safety Workshop

14. Recommend and provide training and authorization (certification) to Electrical Safety Officers (ESO’s) to enable them to perform their duties. • Review training requirements established for SNS staff, support organizations, users, and visitors. • Review Electrical Safety aspects of proposed major facility changes (design reviews and installation recommendations). • Recommend priorities for evaluating and controlling potential Electrical hazards from all sources at SNS. • Review electrical installation, operation and maintenance procedures. • Inspect Facility equipment upon installation or major reconfiguration changes for compliance with NEC and OSHA 29CFR 1910 S. SNS Electrical Safety Workshop

15. AUTHORIZATION: The Committee is chartered by the SNS Associate Laboratory Director. The Committee reports to the SNS ES&H Manager. • MEMBERSHIP: The membership shall consist of the chairperson, the SNS Electrical Safety Officers from SNS organizations with significant involvement in electrical work, including Accelerator Systems, Experimental Facilities, and Site Operations. The Committee will solicit other representatives to participate in standing or ad hoc subcommittees as deemed necessary. • MEETINGS: The Committee shall meet as determined by the chairperson, but at least quarterly. SNS Electrical Safety Workshop

16. RESPONSIBILITIES: • The SNS Associate Laboratory Director shall: • Determine the disposition of the Committee recommendations and communicate that disposition back to the Committee and to affected line and program managers of tenant organizations as necessary. • Appoint the chairperson of the Electrical Safety Committee and the Electrical Safety Officers (ESO’s). • The chairperson shall: • Ensure that the Committee carries out the tasks specified in this charter. • Solicit a representative from each organization having significant involvement in electrical work at SNS. • Convene timely meetings. SNS Electrical Safety Workshop

17. Charter subcommittees or ad hoc working group; e.g., for pre-startup readiness reviews. • Ensure that minutes are kept recording Committee actions. • Forward Committee recommendations to the SNS ES&H Manager, as appropriate. • Report ESC activities to the ES&H Manager. • Ensure that records are maintained of the disposition and implementation of Committee recommendations. SNS Electrical Safety Workshop

18. The Electrical Safety Officers shall: • Serve as a subject matter expert to the Committee in areas of Electrical Safety and regulatory compliance as mandated by OSHA. • Ensure that activities at SNS associated with electrical installations, operation and maintenance are carried out in accordance with the ORNL Electrical Safety Program and SNS policies. • Have signature authority to approve changes to the configuration of electrical equipment and installation. SNS Electrical Safety Workshop

19. Have the authority to interpret existing requirements and policies until such time as matters can be brought to the Committee for action. • Serve as active members of the Committee including: • suggesting agenda items for meetings • maintaining a list of Committee members • keeping and distributing minutes of Committee meetings • maintaining the records of readiness reviews for which the Committee is responsible • maintaining records of the disposition and implementation of Committee recommendations SNS Electrical Safety Workshop

20. maintain records of approvals for unlisted electrical equipment • maintain records of electrical distribution systems verification test reports • APPROVED: _________________________________ _____________ SNS ES&H Manager Date • _________________________________ _____________ • SNS Associate Laboratory Director Date SNS Electrical Safety Workshop

21. SNS adopted definitions • 1. The initial activity is new installation. Installation describes the activity where new equipment and associated electrical wiring is installed. Good engineering and planning of installation shall prevent exposure of personnel to hazardous energies, i.e., no work shall be performed on energized (live) parts, as described in NFPA 70E Standard for Electrical Safety Requirements for Employee Workplaces. SNS LOTO, if necessary, shall be fully enforced including JHA (job hazard analysis). • 2. The second activity is verification and testing of new installations. Verification describes the activity where the new equipment and the associated wiring is examined and approved as per applicable standards and good engineering practices and subsequently energized. SNS Electrical Safety Workshop

22. Testing describes the activity where energized equipment is being evaluated from safety requirements (testing and measuring of voltages, currents, impedances, etc.) This activity requires work on or near energized (live) electrical parts. The NFPA 70E Standard for Electrical Safety Requirements for Employee Workplace chapter 2 General Requirements for Electrical Work Practices shall be observed. The emphasis is on personnel qualifications, flash boundaries, personal protective equipment and approach distances. Proper planning (JHA) shall minimize hazards to the personnel, e.g. connection of test equipment on de-energized parts. SNS Electrical Safety Workshop

23. 3.The third activity is commissioning under the guidance of operations and area physicists. • This again includes verification and testing as well as proper functionality of integrated electrical systems. This may include verification and testing, therefore all in the second paragraph applies to this activity from electrical safety point of view. • 4. The fourth activity is maintenance. Maintenance describes activity where tested and commissioned equipment is being worked on to keep equipment and associated systems in good operational condition, also known as preventive maintenance. This activity is usually a scheduled activity, where work on energized equipment shall be prevented by all means - SNS LOTO and NFPA70E shall be fully enforced. SNS Electrical Safety Workshop

24. 5. The fifth activity is repair. Repair describes activity where work is being performed on equipment to restore the equipment into a good operating condition, usually after equipment failure. This activity shall be performed with the equipment de-energized. • If the impact of de-energizing of the equipment will cause a significant monetary loss to the project, the project management with operations shall identify such repair work early, possibly during commissioning phase (e.g. CHL), and carefully evaluate the necessity of repairs on energized equipment. Electrical Safety Committee shall be asked for an independent evaluation. • The emphasis again shall be on personnel qualifications, flash boundaries, personal protective equipment and approach distances. Proper planning (JHA) shall minimize hazards to the personnel, e.g. bypassing the energized equipment so the main work can be done on de-energized parts. • Supervisors shall be responsible for currency of qualifications of personnel assigned to perform these tasks. SNS Electrical Safety Workshop

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27. Summary of Electrical Safety Program • Training • Definitions • Qualifications and qualification categories • Hazard classification • JHA • Specific equipment JHA SNS Electrical Safety Workshop