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<td><a href="https://misportal.jlab.org/ll/index.jsf?function=view&lessonId=849">Glove Box Antechamber Door Cracks into Three Pieces at the Environmental Molecular Sciences Laboratory - Pacific Northwest National Laboratory</a></td>
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<h2 style="white-space:nowrap">Statement of Lessons Learned</h2>
<pre>For a copy of the original report, see “Attachments” on Lessons Learned page.
Only tighten glove box doors enough to create an adequate seal. Avoid over tightening as it may stress the equipment. Emphasize to research interns and visiting scientists the proper use of glove boxes and their doors. Inspect both inner- and outer-chamber doors for wear due to excessive tightening. Require researchers to wear appropriate footwear as part of their personal protective equipment (PPE) during laboratory work.
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<h2 style="white-space:nowrap">Discussion of Activities</h2>
<pre>Environmental Molecular Sciences Laboratory researchers put samples in the antechamber of a four-year-old, recirculated-inert-gas glove box, and sealed the door. They continued working around the lab as the chamber purged and refilled with nitrogen to match the atmosphere inside protecting samples and materials from being compromised by oxygen or water. One worker was close enough to hear the antechamber door crash to the floor after suddenly cracking into three pieces. An inspection showed that over-tightening had caused the handle shaft to drill through a plastic spacer and bore a depression into the center of the circular aluminum door, weakening it over time until it failed.</pre>
<h2 style="white-space:nowrap">Analysis</h2>
<pre>Manufactured by Innovative Technology in 2010, the glove box includes a small antechamber with an outer door made from a flat disc of half-inch-thick aluminum alloy. The door is designed to seal snugly against a large O-ring when a handle is turned. The staff member working near the glove box reported that the door failed while the antechamber was filling with nitrogen. The cycle of creating a vacuum in the chamber and re-pressurizing with nitrogen may have stressed the metal, but over-tightening was also considered a factor in the door failure.
The user manual does not address the issue of over-tightening and staff members were not cautioned against it. The manufacturer is aware of the design issue and over-tightening concerns and has redesigned the door. Newer models feature different doors.
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<h2 style="white-space:nowrap">Recommended Actions</h2>
<pre>Below are the consequences of the above event. They are provided for information and discussion purposes only.
This event highlights the potential for unexpected equipment defects. While no one was injured, the event demonstrates that even certified equipment may be hazardous when incorrectly fabricated or assembled.
This incident provides several important lessons that can help PNNL staff members avoid similar incidents in the future.
1. Expect the unexpected. Even Nationally Recognized Testing Laboratories (NRTL)-listed equipment may not perform as expected. When this happens, make sure the equipment is thoroughly tested by qualified electricians.
2. Stop and report events immediately. No matter how insignificant a shock or other unexpected event seems at the time, stop work immediately and report the situation to management.
3. Reinforce PNNL expectations. TOR-2s are responsible for briefing and reminding on-site subcontractors and vendors about PNNL event-reporting requirements--and for overseeing their work to verify that they understand and follow requirements.
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<h2 style="white-space:nowrap">JLab Preventive Measures</h2>
<pre>Jefferson Lab does not have this type of glovebox on site. All glovebox purchases are reviewed and inspected during installation. Training is provided to individuals prior to initial use.</pre>
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<h2>Comments</h2>
<h5 style="white-space:nowrap">9/24/2014 1:43:25 PM by Bailey, Mary Jo</h5>
<pre>Submitted to those current in:
SAF137: Chem Room Safety</pre>
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<legend>Summary</legend>
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<td class="label" nowrap>Lesson ID:</td>
<td class="dataval">849</td>
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<td class="label" nowrap>Status:</td>
<td class="dataval">OK</td>
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<td class="label" nowrap>Doc ID:</td>
<td class="dataval">2014-JLAB-849</td>
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<td class="label" nowrap>Priority:</td>
<td class="dataval">Info</td>
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<td class="label" nowrap>Safety Related:</td>
<td class="dataval">NO</td>
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<td class="label" nowrap>Originator:</td>
<td class="dataval">Bailey, Mary Jo</td>
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<td class="label" nowrap>Issued:</td>
<td class="dataval">9/24/2014 1:42:28 PM</td>
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<td class="label" nowrap>Approved By:</td>
<td class="dataval">Bailey, Mary Jo</td>
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<tr class="row">
<td class="label" nowrap>Approved On:</td>
<td class="dataval">9/24/2014 1:43:25 PM</td>
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<td class="label">Source:</td>
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DOECRD
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<td class="label" nowrap>Location:</td>
<td class="dataval">PNWL</td>
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<td class="label" nowrap>Cost Savings:</td>
<td class="dataval"></td>
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<td class="label" nowrap>Contact:</td>
<td class="dataval">Patti Ammonet, Lessons Learned/Operating Experience Program Manager (509)375-2275</td>
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<td class="label" nowrap>Queued Emails:</td>
<td class="dataval">0</td>
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<td class="label" nowrap>Sent Emails:</td>
<td class="dataval">0</td>
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<td class="label" nowrap>Viewings:</td>
<td class="dataval">2 times</td>
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<legend>Attachments</legend>
<a name="attachments"></a>
<ul class="lesson_attribute_listing">
<li><a target="_blank" href="https://misportal.jlab.org/ll/downloadAttachment?attachmentId=3361">DOE - ChemicalHood.pdf</a></li>
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<legend>Hazard Issues</legend>
<ul class="lesson_attribute_listing">
<li>Chemicals</li>
<li>Reactions</li>
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<legend>Skills</legend>
<ul class="lesson_attribute_listing">
<li>SAF137: Chem Room Safety</li>
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<legend>Distribution/Notification</legend>
<ul class="lesson_attribute_listing">
<li>*Division Safety Officers (DSOs)</li>
<li>*Safety Wardens</li>
<li>*DOE Notification</li>
<li>*ESH&Q Liaisons</li>
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