<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<p>Kathy,</p>
<p><br>
</p>
<p>Could you elaborate a bit on the nature of the contamination?
Appearance? Chemical composition? We purchase from Fisher
Scientific and VWR. </p>
<p><br>
</p>
<p>If you are referring to crystals, especially in BHF, this is
normal. The concentration of Ammonium Fluoride is very high, often
near saturation and crystallization typically occurs when the
temperature drops. If you see crystals around the cap, local
evaporation is the likely cause. In either case, diluting slightly
with DI water or bringing up the bottle to 23- 25 C should solve
the issue. If you have a large amount of crystals, the chemical
composition might have changed. It is hard to say without
pictures. Note that HF (not BHF) should not have crystals.</p>
<p><br>
</p>
<p>Prashant</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 7/2/2026 11:20 AM, Kathy Anderson
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:BYAPR11MB2727779A67BD99EA3B8967D6E7F52@BYAPR11MB2727.namprd11.prod.outlook.com">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Hello Lab Network,</div>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
What is your lab's strategy to minimize the occurrence rate of
receiving incoming boxes of H2SO4 or HF bottles with chemical
contaminating the inside of the box and/or the outside of the
bottles?</div>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Do you have a preferred vendor or vendors you avoid for this
reason? We are experiencing this phenomenon sporadically from
multiple vendors. Some respond by wrapping their bottles or the
rims of bottles before shipping for a time, but not
indefinitely, and some are only willing to replace.</div>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Kathy</div>
<div id="Signature" class="elementToProof">
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<table cellspacing="0" cellpadding="0" border="0"
style="text-align: left; background-color: rgb(255, 255, 255); margin: 30px 0px; width: 100%; color: rgb(71, 73, 74); box-sizing: border-box; border-collapse: collapse; border-spacing: 0px;">
<tbody>
<tr>
<td
style="text-align: left; vertical-align: top; width: 110px;"><span
style="font-family: myriad-pro, sans-serif; font-size: 17px; color: rgb(71, 73, 74);"><img
alt="Block U Logo" width="110"
style="width: 110px; height: auto; max-width: 100%; display: block;"
src="https://digital.utah.edu/wp-content/uploads/sites/2/2024/08/block-u-signature.png"
moz-do-not-send="true"></span></td>
<td
style="text-align: left; line-height: 1.2; vertical-align: top; color: rgb(128, 128, 128);">
<div class="elementToProof"
style="text-align: left; line-height: 1.2; font-family: Arial;">
<span
style="font-size: 14px; color: rgb(102, 102, 102);"><b>Kathy
Anderson</b></span><span style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(102, 102, 102);"><b><i>Chemical
Engineer III</i></b></span><span
style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(128, 128, 128);">Utah
Nanofab</span><span style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(128, 128, 128);">The
University of Utah</span><span
style="font-size: 12px;"><br>
O: </span><span
style="font-size: 12px; color: rgb(128, 128, 128);">801-213-6555</span><span
style="font-size: 12px;"> | C:
</span><span
style="font-size: 12px; color: rgb(128, 128, 128);">801-440-1465</span><span
style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(128, 128, 128);"><a class="moz-txt-link-freetext" href="https://www.nanofab.utah.edu">https://www.nanofab.utah.edu</a></span><span
style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(128, 128, 128);">36
S Wasatch Drive Suite 2500</span><span
style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(128, 128, 128);">Salt
Lake City, UT 84112</span><span
style="font-size: 12px;"><br>
</span><span
style="font-size: 12px; color: rgb(102, 102, 102);"><i><a class="moz-txt-link-abbreviated" href="mailto:kathy.anderson@utah.edu">kathy.anderson@utah.edu</a></i></span></div>
</td>
</tr>
</tbody>
</table>
<div class="elementToProof"
style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre wrap="" class="moz-quote-pre">_______________________________________________
labnetwork mailing list
<a class="moz-txt-link-abbreviated" href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a>
<a class="moz-txt-link-freetext" href="https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork">https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a>
</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
Prashant Srinivasan
Teaching Cleanroom Engineer
Electrical & Computer Engineering
Univ. of California Santa Barbara
<a class="moz-txt-link-freetext" href="https://www.ece.ucsb.edu/department-resources/electronics-shop/tcr">https://www.ece.ucsb.edu/department-resources/electronics-shop/tcr</a></pre>
</body>
</html>