From: Nicole Wilb <nicole.wilb**At_Symbol_Here**GMAIL.COM>
Subject: Re: [DCHAS-L] Runaway Hot Plates
Date: Mon, 27 Apr 2015 10:18:31 -0400
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: CALRTg2ZPCG31F-zJ9XxmaTm9ZBWh4UoGau1TPtwd3E0JM8E5rw**At_Symbol_Here**mail.gmail.com
In-Reply-To


Hello everyone,

This type of hot plate runaway can also happen with Corning plates. We had three incidents in our chemical department in 2013, when Corning 420 or 420D plates at minimum temperature started running to there maximum, putting the oil bath on fire! Such incidents are also described in other institutions; see http://www2.lbl.gov/ehs/Lessons/pdf/FinalHotPlateLL.pdf or http://ehs.ucr.edu/laboratory/hotplatesafetyadvisory20110715.pdf.
We cut off the heating line on all the Corning 420 and 420D hot plates in the chemistry department and let the researchers use them as stirring plates only. EH&S paid a portion of new IKA hot plates, as replacement.

Nicole

Nicole Wilb

Chemical safety manager

EH&S

Universit=C3=A9 de Sherbrooke




On Wed, Apr 22, 2015 at 12:29 PM, Nick Waddell <n-waddell**At_Symbol_Here**northwestern.edu> wrote:

Hi Everyone

I am one of the authors of the poster from Northwestern (http://bit.ly/1DB45ee). We have had a few incidents of runaways ourselves, mainly with the older Corning hot plates. To help get rid of the potentially dangerous ones, we offered an exchange program. Our office was able to get funding, so we purchased 50 hot plates with temperature limits and external probe, and 50 stir-only plates (really fancy ones, too!). I sent out a Google Poll asking labs how many old/non-working hot plates (with a concentration on the Corning model) they had for exchange. We ended up giving labs a new hot plate for every 3-4 they turned in, and a new stir plate for each 1 they turned in, depending on what they requested. Some labs did not get as many hot plates as they wanted, while others wanted only stir plates and got everything they asked for. Our emphasis was twofold:

1. Some labs were using the combination hot/stir plate when only stirring is necessary. We used this as an opportunity to raise awareness of the best practice of using a stir-only plate, especially when only stirring is required of flammable solvents.

2. Some labs were using combination plates where the heating mechanism or the stirring mechanism was broken. We were able to help the lab identify which plates they should get rid of, and the exchange provided an incentive to follow-through.

Another side effect of raising this awareness was the fact that many labs had hot plates with safety controls, but were not using them. I did a presentation on how to set these controls, when to use them, and the proper set points.

At first, a few labs balked at the idea because we were not doing a 1:1 exchange of hot plates, but they all seemed to come around. Some labs didn=E2=80™t even want any plates in return, they just had old ones sitting around that were broken and never used. This was a great opportunity to get those out of the lab and get them

Feel free to contact me if you have any questions. This was quite the interesting process to go through, and really did a nice job raising awareness of this potential problem.

Nick

Nick Waddell, JD, CSP

Senior Lab Safety Specialist

Northwestern University

Office for Research Safety

n-waddell**At_Symbol_Here**northwestern.edu

From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of margie.brazelton**At_Symbol_Here**AM.DYNONOBEL.COM
Sent: Wednesday, April 22, 2015 9:36 AM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] Runaway Hot Plates

i have never seen a hotplate 'run away' when in the off position. we use only corning brand hotplates here. thanks for the info and something else to be aware of!


Best regards,
Margie Brazelton
Senior Process Chemist

Dyno Nobel Inc.
A business of Incitec Pivot Limited
Cheyenne Plant, P.O. Box 1287 / Cheyenne, WY 82003, 8305 Otto Road / Cheyenne, WY 82001, USA
Office: +1 307 637 2766 | Fax: +1 307 771 5637 | Mobile: +1 307 631 8368
mailto:margie.brazelton**At_Symbol_Here**am.dynonobel.com
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Groundbreaking Performance Through Practical Innovation



From: "Pickel, Joseph M." <pickeljm**At_Symbol_Here**ORNL.GOV>
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Date: 04/21/2015 07:55 PM
Subject: [DCHAS-L] Runaway Hot Plates
Sent by: DCHAS-L Discussion List <dchas-l**At_Symbol_Here**MED.CORNELL.EDU>





In the past year, we have had a series of issues with "runaway" hot plates. In the first instance, a hot plate in the off position began heating in an unoccupied laboratory resulting in a hood fire. Since then we've observed another hot plate that was heating while in the off position as well as a hot plate that heated uncontrollably while on a low setting. The hot plates that were in use were all relatively new and issues look to be caused by failed circuit boards.

I presented some of the lessons that we learned from these events at the recent ACS National Meeting and was surprised with how many researchers stopped by my poster to indicate that they have observed the same issues. Descriptions of some of these events and additional details can be found at the following links:
https://opexshare.doe.gov/lesson.cfm/2014/12/11/4670/Electronic-StirrerHot-Plate-Malfunction-Inside-Glove-Box
http://www.research.northwestern.edu/ors/forms/CSHEMA%20Hotplate%20Poster%202014.pdf
https://www.drs.illinois.edu/News/Warning-about-malfunctioning-hotplates

We're advising our folks to keep hotplates unplugged when not in use and use stirring-only hotplates where possible. In addition, some groups are considering getting rid of their existing hotplates and buying new models, but I fear that these may have the same potential issues. The possibility of installing an on/off switch on the cord has also been discussed, and while this will prevent hot plates from heating while in the off position, it might not help the issue of hot plates running away (uncontrolled) when the hot plate is intentionally turned on.

I'd like to poll the group- has anyone else had similar issues, and more importantly... what kind of solutions have you identified?

Thanks,
Joe Pickel


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