CLASSE Safety Training PDF
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Cornell University
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Summary
This document provides safety training for CLASSE, the Cornell Laboratory for Accelerator Based Science and Education. It covers safety procedures for different labs including Wilson Lab, Newman Laboratory, and the Physical Sciences Building. Emergency procedures, including fire and beam-related incidents, are also outlined. The document covers safety policies for working with high-intensity x-ray radiation, and particle accelerators. It describes the different roles and responsibilities of staff and researchers.
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CLASSE Safety Orientation: C LASSE - Cornell Laboratory for Accelerator Based ScienceS and Education ○ Engaged in particle accelerator research and high-intensity/energy x-ray radiation ○ RPE - Radiation Producing Equipment...
CLASSE Safety Orientation: C LASSE - Cornell Laboratory for Accelerator Based ScienceS and Education ○ Engaged in particle accelerator research and high-intensity/energy x-ray radiation ○ RPE - Radiation Producing Equipment ○ One of few facilities with similar capabilities ○ High-Magnetic-Field (HMF) project adds a never before seen x-ray and magnetic field combination beamline Wilson Lab ○ Six floor accelerator science laboratory ○ CHESS (Cornell High-Energy Synchrotron Source) Visiting researchers use x-rays produced by CESR at beamlines ○ CESR (Cornell Electron Storage Ring) Accelerator Complex Half-mile circumference, 40 ft underground Use e+ only now, but used to use both e+ and e- in“pretzel orbits” Still converts e- to e+ in the linear accelerator(LINAC) LINAC creates e+ and injects into synchrotron Synchrotron accelerates e+ to desired energy (6 GeV) Accelerated particles injected into CESR to store collected beam for CHESS ○ Layout Floor 1 LINAC/Synch./CESR Tunnel CHESS Experimental Floor Chemistry Lab/Sample-prep areas Machine Shop CHESS User Office Vacuum Lab Floor 2 CESR Control Room CHESS Equipment Platform Offices Floor 3 Offices Cryogenic and electrical equipment spaces Floor 4 Water & mechanical systems Transformer pad Floor 5/6 Building air handlers and cooling towers Newman Laboratory ○ Six floor physics lab (location of early particle accelerators) ○ SRF (Superconducting Radio Frequency) Group Studies superconductivity in high-frequency regime Cavities produced are used in high-energy accelerators and synchrotron light sources ○ CBB (Center for Bright Beams) Studies how to increase intensity of particle beams while decreasing cost of technologies ○ CMS (Compact Muon Solenoid) One of two large general-purpose particle physics detectors used at LHC at CERN Group at Newman operates and maintains aspects of the pixel detector in CMS ○ Layout Basement SRF Pits/Clean Rooms Main chemistry room Student machine shops 5-ton/10-ton crane areas CBB research areas X-ray beam welder Ground CMS Lab Newman Professional Machine Shop Floor 1 Photocathode Development Lab Faculty/Staff Offices Floor 2 Photocathode Epitaxy and Beam Experiments (PHOEBE) Lab Faculty/Staff Offices Floor 3 Faculty/Staff Offices Floor 4 CBB Lounge/Patio Physical Sciences Building (PSB) ○ CLASSE has lab spaces on 3rd and 4th floors dedicated to: Cosmology New instrumentation for measuring microwave radiation in the universe Muon g-2 Precise gyromagnetic ratio of the muon HEP Theory Research on string theory, string cosmology, collider physics, lattice gauge theory, an others CMS (Compact Muon Solenoid) Emergency/Accident ○ Call (607) 255-1111 from a non-Cornell phone ○ Call 911 from a Cornell phone ○ Use yellow-box emergency phones ○ Notify Supervisor/Group Lead/Safety Director ○ Fill out an accident report within 24 hours Fire ○ Activate the nearest pullbox (if not already activated) ○ Call CESR control room ○ Exit building using stairs not elevators and staying low to the ground ○ Do not re-enter until alarm has been silenced and “all-clear” announcement is made Beam Phones ○ Used to page personnel around Wilson and Newman labs ○ T o use switch the radial dial to a channel, press in the button near the dial to transmit over PA ○ Then, announce who you’re looking for and what channel you’re on ○ Wilson Tunnel phones can only access channels 1-5 ○ When done, reset dial to 12 or 0 CLASSE General Safety Policies ○ Before any work begins, supervisors and employees must ensure that: For any new large projects, a written Safety Plan has been reviewed and is in place All required training for task has been taken Personal Protective Equipment (PPE) is available, in good condition, and worn properly Safety Data Sheets (SDS) are available for any hazardous material ○ Radiation badges are required in all Radiation-Controlled Areas (RCAs) ○ Report all accidents, injuries, and exposures in the Cority system, accessible as a quick link in the safety handbook CLASSE Two-Person Rule ○ No operation involving a known hazard shall be carried out by any one person working alone Ex: Working with V > 50 V, hazardous materials, heavy machinery, and/or moving large equipment ○ No known risk is considered eliminated until two competent persons have agreed to this CLASSE Stop Work Authority ○ All personnel have the authority and obligation to stop any activity that appears to pose an immediate safety hazard MUST cease work if asked to do so for safety reasons ○ Upon stopping work, the supervisors of those involved and the CLASSE Safety Director and/or Manager must be notified ○ Woyk may not resume until a satisfactory resolution is reached CLASSE Safety Contacts ○ CLASSE Safety Director – Jim Shanks (js583) ○ CLASSE Safety Manager – Rigel Lochner (rfl67) ○ CHESS Safety Officer – Dana Richter (der4) General Radiation Safety Training: Roles & Responsibilities ○ CESR Operators Responsible for all RPE related to CESR Primary contact for emergency personnel, and Wilson lab when outside of working hours Trained in the interlock check procedure, machine operations, visitor radiation badge signout, and to search and secure the CESR exclusion area Coordinates with CHESS users via the CHESS Operator ○ CHESS Operators Supervise X-ray operations at CHESS beamlines On duty whenever CHESS experiments are present Issues badges and dosimeters to visitors/CHESS users ○ Beamline Scientists and Staff Assists in performing, and provides oversight of experiments at CHESS beamlines Must be trained as an RPE operator Ionizing Radiation ○ Radiation – the movement of energy via an electromagnetic wave or particle To ionize, radiation must have sufficient enough energy to free electrons from atoms when it interacts with them If it is in the form of an EM wave, (rather than, say, a helium nucleus or alpha particle), this is to say it must fall at or above the frequency of ultraviolet Units of Measure Background Radiation ○ Consists of natural and artificial sources Cosmic rays, uranium, thorium, potassium, internal sources (K40, C14), food, air, building materials, our bodies Smoke detectors, medical imaging/radiotherapy procedures, consumer products Average annual radiation dose from background sources 310 mrem Additional 310 mrem added to annual average due to medical procedures Biological Effects ○ Ionization can happen anywhere inside of an organism Direct Action: Ionization breaks molecular bonds in DNA Indirect Action: Ionization occurs outside of DNA, creating free radicals that break molecular bonds in DNA via chemical interaction ○ Most damaging to cells that are rapidly dividing Skin, Red/White Blood Cells, Human Embryo in Early Development Acute Radiation Exposure ○ Short-term (acute) exposure to large amounts of radiation can cause illness and even death ○ Received over a matter of seconds to a few hours ○ Also referred to as Acute Radiation Sickness (ARS) ○ Overwhelms and kills internal organs/systems before cells have a chance to respond ○ S ymptoms are deterministic (if A, then B), which require a specific level of exposure (threshold) ○ Acute doses of less than 25 rem have no clinically detectable effects ○ Lethal Dose to 50% Exposed (LD50): 400 rem ○ LD100: 1000 rem Chronic Radiation Exposure ○ Received over years ○ Effects are stochastic (if A, then possibility of B) Risk of developing cancer increase with dose Large statistical uncertainty at low doses ○ Linear-No-Threshold Model Assumes some risk of biological damage atanyexposure Difficult to prove at low doses due to other health effects Assumes the worst at low doses Basis for radiation safety protocols Radiation-Induced Cancer Risk ○ In a lifetime ~42% of people will be diagnosed with cancer due to reasons other than radiation exposure ○ A single 10,000 mrem exposure increases one’s chances of contracting cancer by 1% ALARA ○ “As Low As Reasonably Achievable” ○ NYS regulations require an established ALARA program as part of any radiation safety program ○ Keep doses ALARA by Minimizing time spent near known sources, whenever possible Maximizing distance from known sources, whenever possible Making use of shielding (blocking sources with materials) ○ 95% of those who wear radiation badges accumulate no measurable dose (6 MeV) ○ Materials such as Fe, Cu, Ni, are most susceptible ○ Typically occurs in locations with highest particle loss LINAC, transfer lines, and collimators ○ Anything>0.05 mrem/hris considered activated byCLASSE policy Minimum detectable dose rate Activated materials may not leave controlled areas without permission from Safety Director (SD) or Safety Manager (SM) ○ Exclusion areas must be surveyed and activated materials identified prior to moving to “Open Access” ○ Survey must be performed prior to Converter Cave work Sealed Source Surveys ○ Sealed sources primarily used to verify and calibrate detector response ○ Surveys on sources are done to check current source activity ○ To survey sources, one must be listed on the source permit (as well as completed a certain training course track) Portable Meter Anatomy ○ Probe and meter ○ Some meters can accommodate different probes Gamma Probe Technology ○ “Pancake” Probe Thin window on one face Greater sensitivity to low-energy betas and photons C alibrated using Cs-137 (662 keV), can over- or under-respond at other energies Useful for detecting radiation sources, including low levels of radiation Not the best for accurate determination of exposure rate ○ Energy-Compensated Probe Detector shroud designed to attenuate lower energy gamma/x-ray radiation, flattening the energy-response curve Best for accurate determination of exposure rates Geiger-Muller Tube Saturation ○ Meters that require manual scale adjustment can saturate if exposed to radiation levels off-scale Some auto-adjust Long periods of saturation could damage the meter ○ If saturation occurs, remove the meter from the source and press the RESET button if there is one ○ To avoid saturation in the first place, approach the source slowly and adjust the scale accordingly Neutron Probe Technology ○ Requires a different probe ○ BF3 or He filled probes surrounded by a neutron moderator material Moderator may be up to 12 in thick for high-energy neutron detection ONLY used for neutron dose rates ○ ○ Has a slow response Meters at CLASSE ○ Canberra ADM-300 Paired with NP-100 neutron probe Ergonomic digitally reading handheld meter Internal gamma/beta probe External ports allow connection of different probes Audio OFF on startup ○ Johnson Model GSM-115 Most prevalent at CLASSE Basic analog meter Manual scale adjustment required 0.02-200 mrem/hr scale range Checking battery and probe voltage requires setting to specific scale (x1 for battery, x100 for probe) Uses 9V batteries, should be replaced if V < 8V Typically accompanied by a gamma probe, either style ○ Johnson GSM-500/DSM-500 Modern version of above Auto-checks battery/probe voltage Auto-adjusts scale Audio OFF on startup 0.02-200 mrem/hr scale DSM-500 (digital version) can read higher rates ○ Microrem Meters Ludlum Model 19 Manual scale adjustment and battery voltage check ○ Battery should be replaced if outside “BAT OK” area Dual scale meter ○ RED 0-25 μrem/hr ○ BLACK 0-50 μrem/hr Dial setting matches which scale to read ○ Located in Wilson loading dock cabinet Johnson GSM-501/DSM-501 Similar to GSM-500/DSM-500 ○ Auto voltage check and scale adjust ○ Audio OFF on startup ○ Internal beta/gamma probe Beta window at front of meter ○ Located in survey cabinet in Wilson 215 Meter Operations Check ○ Before using any meter, ○ Look for any DO NOT USE labels/markings on both probe and meter ○ Check calibration sticker (calibration occurs annually, contact Safety Manager if meter is out of date) ○ Check battery voltage > 8V, if not replace batteries ○ Verify meter responds to a check source ○ Flex cable to ensure it does not yield unusual behavior ○ Check background level away from source (0.01-0.05 mrem/hr) ○ If a meter fails an operations check Mark DO NOT USE with name and date Contact Safety Manager Response Time and Sound ○ There may be a dial or switch to change between slow and fast responses (determines how quickly the needle on the scale moves) ○ It is generally recommended to have Audio ON when surveying (some meters start with Audio OFF) Background Radiation ○ Typically between 0.01-0.05 mrem/hr ○ Provides context for surveying areas/materials Must be documented when performing shielding verification surveys ○ Can also be used to determine meter functionality If background rate reading is unusual in a familiar location, this could indicate an issue with the meter Verify with second meter Surveying ○ Ensure the probe is correct for the survey (always verify with a second meter if questioning) ○ Ensure use of the sensitive area of the probe ○ Survey at a speed of around 1-2 inches per second ○ If measuring to identify radiation areas Check dose rate on-contact and at 30 cm On-contact measurements >= 2 mrem/hr must also be read at 30 cm If dose at 30 cm exceeds 5 mrem/hr, radiation area restrictions must be put into effect Shielding Survey Documentation ○ Persons(s) performing survey ○ Date/Time ○ Meter/probe info ○ Background rates ○ SUrvey conditions ○ Locations surveyed/measured rates ○ Map indicating survey locations (optional) Basic Electrical Safety: ○ Cornell Electricity Supply Produced at AES Cayuga, supplied to the grid, and distributed to Cornell’s Maple Ave substation At Maple Ave, Cornell co-generates electricity using two 15 MW natural gas turbines Cornell Combined Heat and Power Plant (CCHPP) generates approximately 180 GWh/yr Wilson lab has two 13.2 kV circuit feeds from the Kite Hill substation (central campus) and one 13.2 kV feed from State campus ○ Voltage Classification < 1kV – Low Voltage 1-35 kV – Medium Voltage 35-250 kV – High Voltage ○ Electrical Hazards Shock Occurs when the human body becomes part of a path through which electrons flow Electrocution Death by shock Arc Blast Explosive release of molten material from equipment cause by high-amperage arcs Arc Flash Part of an arc fault, a type of electrical explosion that results from a low-impedance connection to ground or another voltage phase in an electrical system ○ More than 10 mA of current could be fatal!!! ○ Electrical Protective Devices Overcurrent Device Limits maximum amount of current that can flow through a circuit N ot designed for personnel protection but equipment protection Ground-Fault Circuit Interrupters (GFCIs) Monitor current coming and going from a receptacle Should be used with any temporary wiring circuit, mobile electrical power tools, and always when using electrical power tools in wet conditions Designed to protect personnel Will generally trip with an imbalance of 5-10 mA When using, make sure to test proper operation by pressing the trip button and resetting before use An effective ground has no current unless under a fault condition A ground provides a low-resistance path back to the electrical source Working with Electrical Equipment ○ Reset a tripped breaker only once, if it trips again, there is a problem Never enter a live electrical panel unqualified Never defeat safety interlocks on disconnects or electrical equipment unqualified DO NOT replace 120 V or larger fuses Small equipment fuses are okay to change as long as the equipment is de-energized Remove all jewelry, rings, watches Switch all tools off before disconnecting them from power Keep power cords clear of tools during use Do not use light-duty extension cords in a non-residential situation Do not carry of lift electrical equipment by the power cord Live parts >50V need guarding against accidental contact Never break off the third prong of a plug Never use extension cords as permanent wiring Disconnect and LOCK OUT a power supply (PS) before making any adjustments or completing any maintenance Install a grounding stick if needed ALWAYS Ensure power is off Verify by attempting to switch equipment ON Verify lack of voltage using a DVM Wiring ○ Never tie-wrap a cable to another cable or conduit for support Wires should only be added to cable trays less than 40% full If wires deviate from a cable tray pathway, they must be provided with their own dedicated support ○ Emergency Contact CESR Operator who will notify designated personnel for the specific situation Contact your supervisor DO NOT attempt to fix it yourself DO NOT attempt to enter a flooded area Basic Tunnel Safety: ○ Converter Cave Access Allowed ONLY for good reason Explicit permission form supervisor required Pre-notification of SM required Real-time-readout dosimeter and radiation badge required Eye protection required ○ Tunnel Access Machine On No tunnel access while CESR and synchrotron are operating Violating interlocks will dump beam and begin ramp-down of magnets Interlocks Set Check Power Supply (PS) Status Screen ○ Even is PSs are not on (ON column on PS Status Screen), they may still have primary power and ay bereadyto turn on (READY column on PS m Status Screen) Radiation survey has not been done ○ Take an interlock bypass key if entering while interlocks are set Interlocks Down Radiation survey completed and locations with activation have been indicated Magnet power supplies are locked out Safe to enter the tunnel Tunnel Hazards ○ Radiation Present in three forms at Wilson Lab ○ Radiation produced during accelerator operation Synch. Radiation – visible up through high-energy x-rays Particle loss producing high-energy photons (bremsstrahlung) Neutrons ejected by high-energy particle loss ○ Residual activation due to particle loss Typically a small number of components, close to the accelerator vacuum chamber Present after RPE is disabled Activated materials slated for removal is either shielded in-situ or moved to LS1 to cool down ○ Radioactive materials Sealed sources Infrequently, there are unsealed samples at CHESS beamlines Under direct control of staff authorized by radioactive material (RAM) permit from Cornell Radiation Safety Committee (CRSC) T unnel access prohibited when producing radiation Interlocks at perimeter of exclusion area will dump beam within 1 ms of interruption Mechanical Sharp edges Tight spaces Slip/trip Synch diffusion pumps (DPs) Hydraulic – high-pressure/high-flow water systems Missing trench or sump covers Special activities Chemical Lead ○ Used extensively for radiation shielding throughout CESR exclusion area ○ Exposure to high levels can cause health issues like anemia, weakness, kidney or brain damage Beryllium ○ Inhalation or contact can lead to beryllium sensitization, chronic beryllium disease, lung cancer Cryogenic Superconducting (SC) elements in CESR require use of liquid and gaseous helium and nitrogen Can cause cold burns Catastrophic local venting may generate an oxygen deficiency hazard If you see a cryogen cloud in the tunnel, leave immediately Magnetic Permanent magnets in vacuum pumps, wigglers, and undulators can disrupt medical implants or draw in metallic tools Specific concerns involving magnetic fields and medical implants should be taken up with the SD or SM Noise Significant background noise can make communication a challenge in certain places Where hearing protection when working in proximity to loud equipment Fire High cooling airflow rapidly carries smoke, fans flames In case of fire, pull the crash cord and exit te CESR tunnel immediately Electrical Contact with voltages >50 V can cause electrocution Voltages >500 V can easily draw an arc through the air without direct physical contact Even at low voltages, high currents flowing through conductors are significant hazards ○ Dropping a metallic tool and shorting out a conductor can result in arc blast (molten material, blinding flash) If you are working close enough to the hazards shown in the presentation that you may drop a tool in the conductors or if you would be concerned if that hazard were to unexpectedly become energized YOU MUST LOCK OUT THAT POWER SUPPLY CLUSTER Basics of Power Supply Operation ○ Equipment Protection: One minute countdown to turn-off if any of the following conditions are met White or Brown radiation interlock key is removed CESR Operator’s key is removed Any radiation interlock for CESR exclusion area is broken If any of the above conditions are met, RPE is disabled immediately and beam is dumped Normally, no access to tunnel when CESR or synchrotron magnets are powered R eady chains protect hardware at all times, and turn off power supplies Example of trip-actions Magnet System Delay Timer finishes countdown Power outage Over-temperature faults PS malfunction Loss of cryogenic coolant CRASH Button/Cord Activated CESR or Synchrotron Magnet Safety Switch is thrown Ready chains can be checked using cxc (text-based) or chains (GUI) Magnet Bypass Mode ○ Allowed only for necessity, never convenience Examples of valid magnet bypass Magnet PS testing Resetting distributed vacuum pump PSs Magnet IR scans ○ More on Electrical Hazards Magnet PSs are grouped into two magnet clusters Synchrotron Cluster CESR Cluster ○ Dipoles powered in series, therefore servicing dipoles requires locket of CESR magnet cluster ○ Quadrupoles are powered in parallel Electrical hazard contact points include: Uncovered buswork Open electrical cabinets or panels Metallic water fittings in contact with electrical leads Water spray or puddles in contact with electrical leads ○ Pulsed Magnets Most magnets in CESR are DC Exception: pulsed magnets for injection, excitation Thousands of volts and amperes for a fraction of a second Not regularly locked out ○ Misc. High Voltage Vacuum system – up to 5kV Beam Loss Monitors (BLMs)/Beam Spill Detectors – up to 1kV High-voltage cables are typically either RED (North Arc) or tiger-striped (South Arc) ○ PS Locations Synch. Magnet Cluster CESR Dipole Cluster CESR Quadrupole Cluster Superconducting Damping Wigglers Advanced Tunnel Safety ○ Special Magnet System Lockout Applies to these systems: Synch. Magnet Cluster ○ Main guide field magnets, L0 & L3 quadrupoles, and PSs CESR Magnet Cluster (non-SC) ○ DC magnets: Dipoles, quadrupoles, steering correctors, sextupoles, skew quadrupoles, skew sextupoles, octupoles, calibration winding, DQ shunt, and their PSs DOES NOT apply to: All LINAC magnets and PSs Synch. ○ Kicker coils, correction quadrupoles in L0-L5, and PSs CESR ○ SC wigglers (L1 & L5), permanent magnet wiggler and undulators, and PSs All pulsed magnets and PSs ○ Group Lockout Equipment Cluster Collection of equipment that must ALL be locked out to secure a hazard Group Lockout Lock out of equipment cluster(s) for one or more groups of people Lockboxes in Control Room 2 for general use 2 specially labeled for Magnet Clusters Group Lockout Coordinator P erson who verifies all appropriate equipment clusters have been locked out Coordinates equipment access with all working groups Usually CLASSE Facilities Engineer (schedules access tasks), if not it will be whoever is in charge of scheduling the access tasks, if the access is unscheduled, it will be the CESR Operator CESR Operator will know who Group Lockout Coordinator Group Lockout Procedure (After Normal Down Days) ○ Verify at PS Status Screen that all active PSs indicate ON and Primary Power Run down and turn off Ss CESR Cluster – OFF button CRB.15.04 Synch. Cluster – Follow procedure CRA.05.10 OR use turnoff_magprogram De-activate energy sources one-by-one Follow the list in Control Room which gives the easiest path for LTV Go to Lock Point, IDENTIFY THE PROPER LOCK POINT (DOUBLE CHECK) De-energize breaker and extract Kirk Key Return all Kirk Keys to the Control Room Place them in their Magnet Cluster box, each key in its proper location Close lockbox and use Master Lock to secure Key to Master Lock is to be maintained in the control of the CESR Operator (and passed from one to the next at shift change) Two persons verify completion of lockout Normal Access Day: CESR Operator and Group Lockout Coordinator O ther Situations: CESR Operator, Backup Operator, Director of Operations, CESR Technical Director, or Magnet PS Expert Verify all keys in lockboxes Depress one RESET button on the right side of the PS Status Panel by the Master Cluster Lockboxes and waiting for it to complete its action ○ When activated, will try to reset the interlock chain for each PS (will not turn on PS, but this is the first step to doing so) Each person locking out must verify that all of the Magnet Clusters to be locked out satisfy: PSs OFF PSs missing Primary Power Interlock Safety Procedures Any staff member working on or in proximity of the magnets or PSs MUST place their own lock on the Cluster Lockbox, after verifying that all Kirk Keys are in place MUST also depress one of the RESET buttons to the right of the PS Status Panel and wait for it to complete At the point where there is no more work to be done ○ Verify no voltage to GND on the magnet leads, connections, and PSs, using a DVM Restoring Magnet Cluster PSs ○ After Normal Down Days Check surrounding area is clear of non-essential items Check grounding sticks are removed from electrical equipment CESR Operator makes announcement that PSs will be unlocked Verify control devices in OFF position Remove Master Cluster Lock Remove magnet PS Kirk Keys R eturn Kirk Keys to disconnect point and re-energize breaker Announce that PSs will be turned ON Begin procedures for turning on Magnet PSs (e.g. turnon_magprogram) After Multiple Day Shutdown Checking Buswork ○ Qualified personnel walk around the tunnel to check the connections of all the buswork ○ Ensure working area is clean and free from equipment and other miscellaneous items ○ All bus covers and equipment doors and panels that have been removed are re-installed Equipment Safety ○ Should check that Magnet Safety Switches are in the ON (UP) position, and that water cooling is ON ( watervlvprogram) PS Operation ○ Turning ON Announce that magnet PSs are coming ON Follow instructions posted on Web and in Control Room ○ Synch. Cluster – CRA.05.10 ○ CESR Cluster – Push “PS On” buttons and “Quad Bus Ramp Up” buttons CRB.15.04 OR use turnon_magprogram Routine Setting CESR magnet fields to operating conditions ○ Needed to establish repeatable magnet fields when accounting for hysteresis in the magnets ○ Magnet Ramping – exciting magnets well above their operating field levels to help the iron “forget” any previous magnetic history If you are in the tunnel with Magnet Ramping occurring ○ F ields of magnets and voltages are varying well above their regular operating range ○ Occurs, in general, for all CESR Cluster magnets Special Situations Setting up testing conditions before accelerator startup ○ Used to verify that all PSs are fully functional ○ Used to temperature cycle the PSs to cause early failures ○ Result in the magnet being powered on evening and owl shifts a few days prior to scheduled accelerator startup Basic Procedure ○ After verifying that it is safe to turn on the PSs: Restore previous operational testing conditions Record the status of all PSs over some number of hours or shifts ○ Tunnel access ONLY in Magnet Bypass Mode Always a TWO PERSON operation Examples of Unusual PS/Magnet Testing Situations ○ Testing a PS under load ○ Testing Dipole Bus Voltage drops (tests that bus joints are making good contact) ○ Magnet field measurements (polarity) ○ Synch. magnet tuning – checks capacitor value to resonate at 60 Hz Bypass Mode I (Interlocks Set) Entry to the tunnel when magnets are powered is only for necessity and not for convenience ○ Ex: Testing magnet PSs, Resetting distributed vacuum pump PSs Conditions which permit a person to take access: ○ CESR Operator is in control of who can take interlock keys ○ No more than 2 teams ○ No less than 2 people per team Supervisor must approve their taking access Person signing out Bypass Key must agree to anyone taking access ○ CESR Operator must know where they are going and why Procedure ○ Announce preparation for Magnet Bypass Operation ○ CESR Operator searches tunnel to be sure no personnel inside OR verifies that no one has entered without a key and all keys are returned ○ Bypass Key to be signed out by senior staff member, authorized specifically for this magnet cluster Names of those authorized listed on the Bypass Key storage box in the Control Room Needs to understand the nature of the work to be accomplished Needs to understand who will be involved in the work Assesses the risks ○ THEN Unlocks Bypass Key Signs out key in Bypass Key Logbook Takes Key and Magnetic Warning Sign P uts Magnetic Warning Sign above the CRA.R06 White Key Box Installs Bypass Key in Bypass Switch Panel and activates Now, White/Brown keys can be taken Green/Grey are also allowed during Magnet Bypass but subject to the same restrictions as during operations Bypass Mode II (Interlocks Inactive) Work plan must be approved by SD/SM, CESR Technical Director, and Accelerator Operations Director ○ Need to understand the nature of the work to be accomplished, who will be involved in the work, and the risks involved ○ Rope barriers with notices must be installed at all access points to the tunnel with sentries stationed to monitor those points ○ Two-person search of tunnel to notify any personnel to clear the tunnel ○ Announce over PA before installing Master Bypass Key THEN ○ Unlocks Bypass Key Box ○ Signs out key in MASTER Bypass Key Logbook ○ Takes Key and Magnetic Warning Sign ○ Puts Magnetic Warning Sign above the CRA.R06 White Key Box ○ I nstalls Bypass Key in Bypass Switch Panel and activates Master Bypass Key permits ALL magnet clusters to be turned ON Install Master Bypass Key - NO Interlock keys needed for access Ending Bypass Mode All light beam interlocks RESET All White/Brown keys returned to their storage boxes Operator’s Key re-installed Bypass key may then be removed from its Key Switch Bypass key signed in by someone (often CESR Operator) authorized by senior staff member who signed out the key Violation of Conditions Powering Magnets in Bypass Mode Protection hardware is installed ○ Activated when conditions that keep magnets PSs ON are violated ○ Auto-trips Ring Safety/Equipment Safety Interlock element in each PS ready chain after 2 minute delay ○ Prior to this the control system watches when the Delay Timer is started and waits 1 minute to see if conditions are corrected ○ If not corrected after the first minute, it automatically begins powering down all PSs S ituations that will initiate the Delay Timer (and appropriate corrective action to stop timer) ○ White/Brown radiation interlock key removed (Replace key) ○ CESR Operator’s key removed (Replace key) ○ Any light interlock beam is broken (Call Control Room – CESR Operator will reset light beams) NOTE: The search and reset of the radiation areas that were broken requires all magnets OFF. In principle, this can be done when testing is over; in practice, magnets will have ramped down and CESR Operator will need to reset interlocks before proceeding with testing Troubleshooting and Repairs ○ General Guidelines Working on voltages > 50 V requires two persons Attaching probes to any points with voltages exceeding 50 V requires either: ○ The circuit to be de-energized OR ○ The use of properly insulated equipment, personnel insulating clothing (if appropriate), and flash guard for eyes (if appropriate) Remain a safe distance away from equipment that is using power NEVER undertake a hazardous task for which you are not trained A s a Second Person, be certain that you are aware of all hazards associated with the task ALL Clusters – Main PSs Applies to Transrex, EMI, Alpha, Acme, and other CLASSE PSs USe Kirk Keys to lock/unlock PS M icroswitches ensure doors and panels installed before re-energizing ○ Bypassing of these door switched and re-energizing requires a Second Person Perform all tests at lowest voltage where problem is visible ○ Try to limit amount of energy dissipated when a failure occurs CESR Cluster – Quad Bus Chopper Regulator Failure ○ Power down all magnet PSs ○ Replace card(s) or ○ Replace chopper Pull Disconnect plug Disconnect control cable, power cables, and water Reconnect cables and water Reconnect the Disconnect Plug ○ Return to Control Room and power up magnets Chopper Regulator Troubleshooting ○ Powered During Operations Go into CESR Cluster Bypass Mode Observe Fault LEDs on controller card Replace card(s) (able to be changed with Quad Bus PSs ON) or Replace chopper after powering down Quad Bus and pulling Disconnect Plug Follow General Guidelines when attaching probes Go out of CESR Cluster Bypass Mode ○ During Normal Access CESR Magnet Cluster is powered down Pull Disconnect Plug and connect to portable PS Follow General Guidelines when attaching probes during troubleshooting Reconnect Disconnect Plug when finished ○ Be especially careful of other staff members working in the vicinity Be certain they are aware of the hazards Sometimes require two people: one at PS, one at powered magnet (if separated by some distance) CESR Cluster -Main PSs Troubleshooting Ground Faults ○ Use observations of ground fault monitors where possible (Quad Bus) >run [cesr.magnet]quad_bus_gnd_fault_read R eports current imbalance between + and - busses Short occurs before the first point of imbalance ○ Isolate faulting system Turn OFF other PSs Operate at lowest voltages/currents Pull Disconnect Plugs or electrically disconnect buswork to isolate ground Synchrotron Cluster Replacing fuses or capacitors ○ Use display CRA.04.12 to determine location within the ring ○ Power down all PS and lock out Synch. Magnet Cluster ○ Remove bus covers ○ C heck with DVM before touching - both AC and DC ○ Use grounding stick to ground all terminals ○ Replace fuse and/or capacitor ○ Remove grounding stick, replace bus covers ○ Return to Control Room and test under power Lead Handling Safety: ○ Introduction to Lead Blue-gray heavy metal found in Earth’s crust Primarily used in lead-acid batteries as well as ammunition, pipes, building materials, and solder Enters the body primarily via ingestion and inhalation Does not readily enter the body through the skin, but contaminated skin can lead to accidental ingestion Can lead to both neurological and gastrointestinal effects, as well as anemia, kidney disease and cancer ○ OSHA Standards Permissible Exposure Limit (PEL) – 50 μg/m3 Hard maximum averaged over an 8-hour period Respiratory protection and other PPE requirements shall be in place for routine exposures above the PEL Action Level – 30 μg/m3, averaged over an 8-hour period All surfaces shall be maintained as free as practicable of accumulations of lead ○ Lead at CLASSE Most commonly encountered hazardous material in the facility Primarily used for radiation shielding and vibration dampening Measurable contamination on surfaces within the CESR Tunnel, L0, and other spaces Eating and drinking is prohibited in areas where lead is used Hands should be washed out of precaution after being in such locations Routine cleaning of surfaces assists in keeping areas lead-free Storage Wilson 151, L0E High-bay area Wilson 141, CHESS Technical Workshop Newman B50, High-bay area JBC Storage Warehouse At Wilson and Newman, stored lead shall be in a covered container marked “Lead Storage” (if not practical cover the piece and mark it the same) At JBC Warehouse, lead must be stored on pallets and wrapped with plastic sheeting as well as marked “Lead Storage” Handling Nitrile gloves when handling small pieces of lead (including lead bricks) ○ If torn, discard and replace Leather gloves for bulk lead movement ○ Must be marked “For Lead Use Only” and stored in a segregated container when not in use I f clothing contact is likely, coveralls or lab coats should be worn ○ Contaminated protective clothing must be removed before the end of a work day then cleaned or disposed of ○ Contaminated items must be placed in a closed-container to prevent further contamination, and marked with this signage ○ H ands must be thoroughly washed after any lead handling period, regardless of whether or not gloves were worn Machining The use of power tools, machine shop equipment, and hand tools to machine lead must be approved by one of the following: ○ CLASSE SD/SM ○ CLASSE Rigging Supervisor ○ CLASSE Facility Engineer ○ CHESS Safety Officer Only equipment dedicated to lead to be used All chips and particles must be contained when machining to prevent tracking away from the work area ○ Plastic sheeting, wet wipes, and HEPA vacuums are all approved methods for containing and collecting lead particles and chips D ○ O NOT dry sweep or mop ○ All lead debris must be collected before the end of a work day Sanding, grinding, or heating lead isNOTpermitted All lead waste must be disposed of via EHS Hazardous Waste Group ○ CLASSE Safety Personnel can assist Shielding Lead is a common material for shielding from photon radiation hazards Must be covered (as practical) to prevent accidental exposure or contact ○ Acceptable cover includes paint, foil, aluminum sheets, tape, etc. ○ Materials used to cover lead must be disposed of as hazardous waste Upon installation or alteration of radiation shielding, fill out shielding modification form ○ Forms found in Facility Engineer’s office Compressed Gas Safety ○ Hazards of Compressed Gas Inert Gasses Asphyxiation Cryogens Freezing burns Can cause common materials to become brittle and fracture under stress Boiling and splashing will occur on contact with warmer objects Have a liquid to gas expansion ratio of 700 (tremendous pressure in a closed system) Toxic, must be dispensed in a well-ventilated area Not to be stored in cold rooms or confined spaces Oxidizers S hould not be stored near flammable, greasy, or oily materials Flammable Gasses Fire and explosion Do not store close to open flame or ignition source Do not store acetylene cylinders on their side Corrosive Gasses Accelerated corrosion of materials in the presence of moisture Toxic Poisonous Gasses Extremely toxic To be used only by experts with proper equipment and ventilation Safe Handling and Use ○ Contents should be clearly identified with a stencil, stamp, label, or tag Never rely on cylinder color for identification Should be secured by chains, straps, clamps, or other restraining devices May be attached individually to a wall or bench Regulators Valve outlet connections that prevent mixing of incompatible gasses Reduce pressure of gas supplied from high pressure source to desired working pressure Use proper regulator for gas in the cylinder Only wrenches or tools provided by the cylinder supplier should be used to open or close a valve Ensure proper connection and no leakage (using Snoop leak detector or soap solution) Use appropriate PPE ○ Transportation Use cylinder carts when transporting cylinders D o not drop cylinders or permit them to strike anything violently Always transport them with the valve protection cap in place Storage ○ Should be stored in an area that is well-ventilated Away from sources of what or ignition Protected from weather and against tampering Oxygen cylinders should not be stored in the same area (at least 20 ft between or a firewall 5ft high with a rating of 0.5 hours Poisonous gasses must be stored in a gas storage cabinet (has a leak detector) Must be secured in storage ○ Disposal Considered empty while positive pressure still remains Close valve, mark “empty” Ensure valve protection cap is on Store empties apart from full cylinders Personal Protective Equipment (PPE) ○ A ny physical material or equipment that is placed between the employee and workplace hazards to reduce the injury potential of the hazard ○ The employer must pay for all required PPE, except in the limited cases of safety-toe shoes and prescription safety glasses ○ PPE provided to you is expected to be maintained by you ○ If damaged, return to supervisor for replacement ○ Eye Protection Shall be used to protect the eyes from dust, shavings, sawdust, molten metal, acids, caustic liquid chemicals, intense light, blood/infectious bodily fluids Safety Glasses – Protect against moderate impact from particles produced by jobs such as woodworking, grinding, and scaling Safety Goggles – Protect against impact, dust, and splashes W elding Shields – Protect against eye burns caused by intense light as well as protecting the face from flying sparks, metal splatter, slag chips, brazing, soldering, and cutting Face Shields – Protect the face from nuisance dusts and potential splashes or sprays of hazardous liquids Must be used with safety glasses or goggles ○ Head Protection Hard Hats – Protect the head from falling objects, bumping against fixed objects, and electrical shock and burn Class G (General) ○ Impact and penetration resistant, proof-tested at 2.2 kV Class E (Electrical) ○ Same as above, proof-tested at 20 kV Class C (Conductive) ○ No protection against electrical hazards ○ Hearing Protection Earplugs, earmuffs ○ Respiratory Protection Protect the lungs from harmful dust, fogs, fumes, mists, smoke, oxygen deficiency, gasses, sprays, vapors, biohazards Respirators ○ Foot and Leg Protection Protect feet from heavy objects, sharp objects, molten metal, hot or wet surfaces, and electrical hazards Leggings – Protect against heat hazards such as molten metal and welding sparks Metatarsal guards – Protect instep against impact and compression Toe guards – same as above Safety shoes – impact resistant toes, heat and slip-resistant soles, protection against puncture Ay be designed to be electrically conductive so as to prevent the buildup of static electricity Non-conductive safety shoes Rubber boots Hand and Arm Protection ○ Leather gloves – protect against sparks, moderate heat, blows, chips, and rough objects Synthetic gloves – protect against heat and cold, are cut- and abrasion-resistant and may withstand some diluted acids (do not stand up against alkalies and solvents) Fabric gloves – protect against dirt, slivers, chafing, and abrasions Chemical-resistant (rubber) – protect against chemicals, the thicker the rubber the more chemical resistance, the less dexterity and grip Butyl gloves – protect against peroxide, highly corrosive acids, strong bases, alcohols, etc. Natural (Latex) rubber gloves – protection from most water solutions of acids, alkalies, salts, and ketones Neoprene gloves – good pliability and dexterity, high density and tear resistance; protect against hydraulic fluids, gasoline, alcohols, and organic acids Nitrile gloves – protect against chlorinated solvents, oils, greases, acids, caustics, and alcohols ○ Body Protection Lab coats Coveralls Vests Jackets Aprons Surgical gowns Full-body suits Arc Flash Equipment
