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Every year, in the United States about 1,500 people have surgical objects accidentally left inside them after surgery.Objects have been left in the abdomen, pelvis, chest, thorax, brain, spinal canal, face, extremities and other body areas.. 13-inch long surgical retractor that was left inside a
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1. Foreign Material Exclusion Lessons Learned on Clean Area Controls
at the Advanced Test Reactor
2. Every year, in the United States about 1,500 people have surgical objects accidentally left inside them after surgery.
Objects have been left in the abdomen, pelvis, chest, thorax, brain, spinal canal, face, extremities and other body areas.
3. The Advanced Test Reactor 250 MW Pressurized Water Reactor
Very high neutron flux
Time Machine for Nuclear Fuels and Materials Research
Customizable irradiation environment
Over 40 years as the worlds leading research reactor
4. ATR : A Look Inside
5. Small tolerances in reactor
Element flow is ~600 gpm.
Channel flow is ~ 32 gpm.
Channel size is ~ 3 in long by 0.075 in. (thickness of a nickel)
Experiments also have flow through and around them.
Reactivity control elements, including safety rods, could bind due to foreign material.
6. Operational Background Frequent opening of reactor to fuel / defuel and insert / remove experiments.
Operations include the use of large and small tools, fasteners, monitoring equipment and rags.
Work controls range from skill of the craft to detailed operating procedures.
7. Clean Area Controls Methods employed to control materials
8. Clean Area Controls Methods employed to control materials
9. Clean Area Controls Methods employed to control materials
10. Recent Foreign Material Events Blue rag found in reactor several days after use.
Chain fall spring missing noted by inspection.
Heat stress bulb dropped in tank - noted by watch.
RadCon tape dropped into reactor and pink sticky note fell off binoculars into tank - noted by watch.
Rag stuck in experiment tube (Dec 08).
Metal shavings from long-handled tool.
NEAR MISS (Feb 09)
11. Recent Foreign Material Events Experiment holder and other parts found lying across fuel noted upon opening reactor.
Clamp used in reactor dropped in tank noted by operator.
Washers found on fuel and other components missing noted upon opening reactor.
Experiment components missing from expected location- noted during procedural evolution.
12. Oversight Perspective Most events have recognizable precursors.
Clean Area Watch not controlling the area
Loose Items lying uncontrolled in the clean area
Operators not using lanyards
Rags / tape / etc. not consistently documented
Metal shavings falling out of handling tool
Operations losing focus due to time pressure
Recovery of material does not equal success.
Schedule Impacts for investigations
Cost Impacts ($45,000 camera = 30 seconds use)
13. Lessons Learned Tools are only as effective as the operator.
Consistent standards for tracking material are required.
Clean Area Watch requires effective training and authority, and should have no other duties.
Logbook entries need to be detailed and complete.
Legacy Practices can normalize deviation from approved procedures.
Management oversight and reinforcement of behaviors is required.
Formality and focus by operators and job supervisors are required.
14. Keeping external foreign material out is only half the battle.
Internal origin material requires controls in design.
Material failure modes and recovery should be evaluated before insertion.
Design that minimizes small or loose components.
Defense-in-depth (baskets around components) Lessons Learned
15. Foreign Material Keeping it out can prevent a lot of pain !
