<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<title>Jefferson Lab Lessons Learned : Print Lesson</title>
<base href='https://misportal.jlab.org/ll/'>
<!--[if IE]>
<style type="text/css">
#page_content input[type=checkbox], #page_content input[type=radio] {
background-color: transparent;
border: 0;
}
</style>
<![endif]-->
</head>
<body>
<div id="doc3" class="yui-t7">
<div class='round' id='pageMessages'>
<!-- -->
</div>
<div id="lesson" class="yui-gc">
<style type="text/css">
pre {
white-space: -moz-pre-wrap;
white-space: -pre-wrap;
white-space: -o-pre-wrap;
white-space: pre-wrap;
word-wrap: break-word;
overflow: hidden;
margin-left: 10px;
}
</style>
<div id="topbar">
<div id="lesson_title">
<table width="100%">
<tr>
<td><a href="https://misportal.jlab.org/ll/index.jsf?function=view&lessonId=843">Steam Trap Lid Falls from Vise and Strikes Foot Resulting in a Fractured Metatarsal - Argonne National Laboratory </a></td>
</tr>
</table>
</div>
</div>
<table width="100%">
<tr>
<td valign="top" width="100%">
<div id="maintextcol" class="yui-u first">
<h2 style="white-space:nowrap">Statement of Lessons Learned</h2>
<pre>For a copy of the original report, see “Attachments” on Lessons Learned page.
The decision to use equipment and/or processes based solely on past successes does not always guarantee the best results.
</pre>
<h2 style="white-space:nowrap">Discussion of Activities</h2>
<pre>On May 23, 2014, a Facilities Management and Services (FMS) -Utilities Systems (US) maintenance mechanic placed a steam trap lid, weighing approximately 65 pounds, into a heavy-duty vise mounted on the corner edge of a workbench. While the mechanic used a three-foot long wrench to apply torque to install a center nut on the lid, the vise loosened and the lid rolled out. It fell approximately four feet to the ground striking the mechanic on the left foot resulting in a 1st metatarsal fracture which required surgical repair.</pre>
<h2 style="white-space:nowrap">Analysis</h2>
<pre>The mechanic had twenty-eight years’ experience working with similar vises and torque wrenches; however, this was the first time this particular task had been performed at Argonne. The mechanic had been instructed by another mechanic as to the proper work procedure. It was verified that the instructions were the procedure that has been used by others without incident.. No further instruction or guidance was provided prior to the commencement of work.
The investigation team inspected the vise that was used and found it to be in good working condition. It was noted, however, that the surface area of the lid, when placed in contact with the vise jaws, was minimal due to the curved/rounded surface.
Based on this information, it was concluded that the wrench used to tighten the center nut was almost three times as long, providing three times the torque as the torque provided by the vise handle. The difference, between the vise jaws (with minimal surface area contact between the jaws and the lid surface) versus the torqueing motion on the lid explains how the vise loosened allowing the lid to fall.
</pre>
<h2 style="white-space:nowrap">Recommended Actions</h2>
<pre>The mechanic had twenty-eight years’ experience working with similar vises and torque wrenches; however, this was the first time this particular task had been performed at Argonne. The mechanic had been instructed by another mechanic as to the proper work procedure. It was verified that the instructions were the procedure that has been used by others without incident.. No further instruction or guidance was provided prior to the commencement of work.
The investigation team inspected the vise that was used and found it to be in good working condition. It was noted, however, that the surface area of the lid, when placed in contact with the vise jaws, was minimal due to the curved/rounded surface.
Based on this information, it was concluded that the wrench used to tighten the center nut was almost three times as long, providing three times the torque as the torque provided by the vise handle. Thr difference, between the vise jaws (with minimal surface area contact between the jaws and the lid surface) versus the torqueing motion on the lid explains how the vise loosened allowing the lid to fall.
</pre>
</div>
<div id="comments_div">
<a name="comments"></a>
<h2>Comments</h2>
<h5 style="white-space:nowrap">8/26/2014 9:28:32 AM by Bailey, Mary Jo</h5>
<pre>Submitted to those current in
•SAF502: FORKLIFT OPERATOR</pre>
</div>
</td>
<td valign="top">
<div class="yui-u">
<fieldset>
<legend>Summary</legend>
<table>
<tr class="row">
<td class="label" nowrap>Lesson ID:</td>
<td class="dataval">843</td>
</tr>
<tr class="row">
<td class="label" nowrap>Status:</td>
<td class="dataval">OK</td>
</tr>
<tr class="row">
<td class="label" nowrap>Doc ID:</td>
<td class="dataval">2014-JLAB-843</td>
</tr>
<tr class="row">
<td class="label" nowrap>Priority:</td>
<td class="dataval">Info</td>
</tr>
<tr class="row">
<td class="label" nowrap>Safety Related:</td>
<td class="dataval">YES</td>
</tr>
<tr class="row">
<td class="label" nowrap>Originator:</td>
<td class="dataval">Bailey, Mary Jo</td>
</tr>
<tr class="row">
<td class="label" nowrap>Issued:</td>
<td class="dataval">8/26/2014 9:27:08 AM</td>
</tr>
<tr class="row">
<td class="label" nowrap>Approved By:</td>
<td class="dataval">Bailey, Mary Jo</td>
</tr>
<tr class="row">
<td class="label" nowrap>Approved On:</td>
<td class="dataval">8/26/2014 9:28:32 AM</td>
</tr>
<tr class="row">
<td class="label">Source:</td>
<td class="dataval">
DOECRD
</td>
</tr>
<tr class="row">
<td class="label" nowrap>Location:</td>
<td class="dataval">ANL</td>
</tr>
<tr class="row">
<td class="label" nowrap>Cost Savings:</td>
<td class="dataval"></td>
</tr>
<tr class="row">
<td class="label" nowrap>Contact:</td>
<td class="dataval">Tad Jesionowski, tjesionowski@anl.gov, (630) 252-6883</td>
</tr>
<tr class="row">
<td class="label" nowrap>Queued Emails:</td>
<td class="dataval">0</td>
</tr>
<tr class="row">
<td class="label" nowrap>Sent Emails:</td>
<td class="dataval">0</td>
</tr>
<tr class="row">
<td class="label" nowrap>Viewings:</td>
<td class="dataval">3 times</td>
</tr>
</table>
</fieldset>
<fieldset>
<legend>Attachments</legend>
<a name="attachments"></a>
<ul class="lesson_attribute_listing">
<li><a target="_blank" href="https://misportal.jlab.org/ll/downloadAttachment?attachmentId=3260">M:\wcd\LessonsLearned\Machine Tools\DOE - Yellow - VisePic.pdf</a></li>
<li><a target="_blank" href="downloadAttachment?attachmentId=3261">M:\wcd\LessonsLearned\Machine Tools\DOE - Yellow - Vise.pdf</a></li>
</ul>
</fieldset>
<fieldset>
<legend>Hazard Issues</legend>
<ul class="lesson_attribute_listing">
<li>Tools - Machine & Portable</li>
</ul>
</fieldset>
<fieldset>
<legend>Skills</legend>
<ul class="lesson_attribute_listing">
<li>SAF502: FORKLIFT OPERATOR</li>
</ul>
</fieldset>
<fieldset>
<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>
</ul>
</fieldset>
<!--
<fieldset>
<legend>Applicable Orgs</legend>
<ul class="lesson_attribute_listing">
</ul>
</fieldset>
-->
</div>
</td>
</tr>
</table>
<script language="javascript">
var commentTextarea = document.getElementById("commentForm:commentText");
if (commentTextarea){
var validationErrorFound = commentTextarea.parentNode.innerHTML.indexOf("Validation Error: Value is required.") > -1;
if (validationErrorFound){
// add hash if necessary
if (window.location.hash == null || window.location.hash == "" || window.location.hash == "#"){
window.location.hash = "#comments";
}
}
else {
//JSF likes to hold on to the values entered into the form...so blank them out
commentTextarea.value = "";
commentTextarea.form.elements["commentForm:commentType"].selectedIndex = 0;
var numStars = commentTextarea.form.elements["commentForm:stars"].length;
for (var ii=0; ii<numStars; ii++){
commentTextarea.form.elements["commentForm:stars"][ii].checked = false;
}
}
}
</script>
</script>
</div>
<br>
<br>
</div>
</body>
</html>