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- closed toe shoes
- long pants
- cryo gloves
- face shield
- a cryo apron (can be a hazard on the ladder)
Equipment
- He dewar bubbler (optional if there is a scale)
- It is a long ~8ft section of 3/8" SS pipe with a dropper squeezer on the end. On the bubblier are two zip ties or clamps to help tell volume
- Scale
- 9/16 open ended wrench
- 2x adjustable wrenches
- Balloon grade helium
- All PPE called out above
- Heater Gun
- Ladder
- Measuring tape
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- Bring a new dewar down to the hutch that needs the replacement. Do not ride on the elevator with it!
- Put a the ODM onto the dewar, don't put it right in front of a PRV.
- Teflon tape the horizontal vent valve with the NPT fitting.
- Screw on the "T" manifold and firmly tighten it.
- Roll the dewar into position, if you need to place it on a scale use two people. Be sure to point the "T" manifold in such a way that won't hinder or spay people as the pass by.
- Take off the black cap on the vertical vent valve (keep it nearby) and snip the ziptie on the Low Pressure Relief Valve
- Rip off the "full" tag
- Stap Strap the dewar down with a speed strap.
- Deploy a ladder nearby the dewar so one person could easily reach ~ 6ft over the top of it.
- Put Both people put on all PPE.
- Open the vertical vent valve.
- Grab the stinger and allow one person to climb the ladder then hand the stinger to them.
- With both of you, guide the stinger into the vertical valve all the way to the bottom. Go slowly as the helium will boil off and the pressure will rise. Try not to stand in front of the PRVs and keep the low pressure PRV closed unless you can stand off to the side of it.
- Once it is as far as it goes,
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