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<td><a href="https://misportal.jlab.org/ll/index.jsf?function=view&lessonId=884">Two Events Provide Reminders for Working with Pressure Systems – 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.
Compressed gases can introduce pressure into systems greater than the pressure rating of the system or its components. </pre>
<h2 style="white-space:nowrap">Discussion of Activities</h2>
<pre>Two events at PNNL illustrate the importance of reminding users that compressed gases have great potential to cause damage to equipment and/or to injure staff members if pressure systems are not properly protected. One incident involved a vacuum system built primarily with glass tubing that failed. The other involved a gas dryer that failed. Both were due to overpressure. No one was injured in either incident, but they illustrate the serious consequences that can result when errors are made with systems using bottled gas.</pre>
<h2 style="white-space:nowrap">Analysis</h2>
<pre>Event #1: A researcher, using a system with glass tubing, attempted to backfill the system with ~2 psig nitrogen to relieve a vacuum. She was following a procedure, but was unable to open the system because it was still under vacuum. She increased the nitrogen pressure at the regulator to ~5 psig and tried to open the system again. After she opened the supply valves, a section of the glass tubing failed. The suspected cause was a leaking valve or incorrect valve position (See attached).
Event #2: A dryer or desiccator failed under excessive pressure. It was installed in a system to supply CO2 gas to an instrument. The dryer, whose pressure rating was 125 psi, was placed downstream of the regulator on a CO2 cylinder (~800 psi). The regulator was inadvertently set to a pressure ~250 psi, causing the failure (See attached).
Both incidents resulted from pressure in a system that exceeded the pressure rating of a section or component.
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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.
Know the pressure rating of your system and make sure installed components are rated for the pressure to be used in your work. Use a pressure-relief device to make sure components with the lowest pressure ratings will not fail.
Verify the pressure rating of your system--and its individual components--before starting work. Commonly used at PNNL, dryers or desiccators or other gas scrubbers typically have pressure ratings of 90 to 250 psi.
Limit system pressure to protect components and equipment. Make sure the pressure regulator is set correctly and install a pressure-relief device if system pressure could exceed the rating of individual components or equipment. See the video below for more information.
Ask questions. If you have concerns about your pressurized system, contact the pressure systems engineer.
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<h2 style="white-space:nowrap">JLab Preventive Measures</h2>
<pre>Jefferson Lab’s Pressure and Vacuum Systems Safety Program is outlined within ES&H Manual Chapter 6151 and its associated appendices. Only those who are appropriately trained are authorized to work with these types of systems.</pre>
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<h2>Comments</h2>
<h5 style="white-space:nowrap">5/5/2015 8:42:07 AM by Bailey, Mary Jo</h5>
<pre>Submitted to those with training related to pressure or vacuum systems.</pre>
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<legend>Summary</legend>
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<td class="label" nowrap>Lesson ID:</td>
<td class="dataval">884</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">2015-JLAB-884</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">YES</td>
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<tr class="row">
<td class="label" nowrap>Originator:</td>
<td class="dataval">Bailey, Mary Jo</td>
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<tr class="row">
<td class="label" nowrap>Issued:</td>
<td class="dataval">5/5/2015 8:40:57 AM</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">5/5/2015 8:42:07 AM</td>
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<td class="label">Source:</td>
<td class="dataval">
DOECRD
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<tr class="row">
<td class="label" nowrap>Location:</td>
<td class="dataval">PPPL</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=3820">DOE - Yellow - Two Events.pdf</a></li>
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<legend>Hazard Issues</legend>
<ul class="lesson_attribute_listing">
<li>Pressure Systems</li>
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<legend>Skills</legend>
<ul class="lesson_attribute_listing">
<li>SAF130A: PRESSURE SYSTEMS SAFETY AWARENESS</li>
<li>SAF130B: PRESSURE SYSTEMS SAFETY DESIGN AUTHORITY</li>
<li>EN-34: Vacuum Fundamentals</li>
<li>EN-021: Ability to ensure compliance with the lab's policies and procedures in Pressure Systems </li>
<li>EN-035: Working knowledge of pipes and plumbing, fluid dynamics, and pressure systems</li>
<li>FM-031: In-depth knowledge of the operation, maintenance, compliance, and billing associated with the Lab pressure vessel and potable water distribution sewage systems.</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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Do you have a lesson learned you would like to contribute? Contact the <a href="mailto:cjohnson@jlab.org,sjsmith@jlab.org,mbailey@jlab.org">Lesson Learned Coordinator</a>.