From: "Wright, Mike" <mwright**At_Symbol_Here**USW.ORG>
Subject: Re: [DCHAS-L] 4 more MSDS and GHS
Date: January 29, 2012 3:42:45 PM EST
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: A <40725112.156675.1327765851505.JavaMail.root**At_Symbol_Here**sz0024a.emeryville.ca.mail.comcast.net>


Thanks David. Very much on target, but mostly implemented.

 

Michael J. Wright

Director of Health, Safety and Environment

United Steelworkers

5 Gateway Center

Pittsburgh, PA 15222

 

Work (412) 562-2580

Cell (412) 370-0105

Fax (412) 562-2584

 

mwright**At_Symbol_Here**usw.org

 

Visit us on the web at www.usw.org

 

From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of 8524828hau**At_Symbol_Here**COMCAST.NET
Sent: Saturday, January 28, 2012 10:51 AM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] 4 more MSDS and GHS

 

If not already in place, I recommend installation of alarming (local and remote) hydrogen sensors at the highest location(s) in the work space.  Ideally, the escaping hydrogen could be detected before it reaches its LEL, with subsequent corrective action.  Is the chamber always maintained at a pressure greater than the workspace, thus minimizing the likelihood for introduction of air?  Introduction of air into the chamber will be minimized by the rather inefficient (but safer) practice of avoiding a vacuum step in the purge process.  Finally, installation of a hydrogen sensor in the exhaust line would provide a positive indication that the nitrogen purge had removed hydrogen to some acceptable level.

Not being familiar with the operation/apparatus, I apologize if some of these suggestions are off-target; or are already being implemented.

David Haugen (retired)


From: "Mike Wright" <mwright**At_Symbol_Here**USW.ORG>
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Sent: Friday, January 27, 2012 4:37:24 PM
Subject: Re: [DCHAS-L] 4 more MSDS and GHS


They're called boxes, but they are actually cylinders, typically 8 feet or so in diameter and 20 high. Steel coils are stacked inside with spacers. A crane sets the "box" on its pad, which has a water-cooled polymeric gasket. The air is purged with nitrogen, and hydrogen is then introduced. At the end of the run, the nitrogen purges the hydrogen. The furnaces themselves rarely explode, because it's hard to get under the UEL. The problem is escaping hydrogen.

 

Michael J. Wright

Director of Health, Safety and Environment

United Steelworkers

5 Gateway Center

Pittsburgh, PA 15222

 

Work (412) 562-2580

Cell     (412) 370-0105

Fax     (412) 562-2584

 

mwright**At_Symbol_Here**usw.org

 

Visit us on the web at www.usw.org

 

From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Allen Niemi
Sent: Friday, January 27, 2012 4:51 PM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] 4 more MSDS and GHS

 

I'm sure you are accustomed to flushing the furnace with inert gas prior to introducing the hydrogen. It is very difficult to effectively flush a rectangular box, hence the explosion once the H2 is introduced with residual oxygen still present (also can happen if air leaks back into the furnace during operation).

-----------------------------------------
Allen Niemi, PhD
Director
Occupational Safety and Health Services
Rm 322 Lakeshore Center
Michigan Technological University
Houghton, Michigan 49931
Office: 906-487-2118
Fax: 906-487-3048
anniemi**At_Symbol_Here**mtu.edu



----- Original Message -----
From: "Mike Wright" <mwright**At_Symbol_Here**USW.ORG>
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Sent: Friday, January 27, 2012 3:34:17 PM GMT -05:00 US/Canada Eastern
Subject: Re: [DCHAS-L] 4 more MSDS and GHS

I just reread my own post. I have no idea why I included the word "inert."  In fact, we've had hydrogen fires and explosions in these things.

 

Michael J. Wright

Director of Health, Safety and Environment

United Steelworkers

5 Gateway Center

Pittsburgh, PA 15222

 

Work (412) 562-2580

Cell     (412) 370-0105

Fax     (412) 562-2584

 

mwright**At_Symbol_Here**usw.org

 

Visit us on the web at www.usw.org

 

From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Allen Niemi
Sent: Friday, January 27, 2012 2:15 PM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] 4 more MSDS and GHS

 

Just as an aside, I don't doubt that the annealing furnace was filled with hydrogen but I sure wouldn't call it an inert gas. Flammable or explosive would be a better description. It's used in that type of application to keep the hot metal from oxidizing and even clean up existing oxidation and must be handled with extreme caution.

-----------------------------------------
Allen Niemi, PhD
Director
Occupational Safety and Health Services
Rm 322 Lakeshore Center
Michigan Technological University
Houghton, Michigan 49931
Office: 906-487-2118
Fax: 906-487-3048
anniemi**At_Symbol_Here**mtu.edu



----- Original Message -----
From: "Mike Wright" <mwright**At_Symbol_Here**USW.ORG>
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Sent: Friday, January 27, 2012 12:35:48 PM GMT -05:00 US/Canada Eastern
Subject: Re: [DCHAS-L] 4 more MSDS and GHS

RCF is ubiquitous in industrial plants which use hot processes, and despite the ACGIH TLV, there's no specific OSHA standard. That's because it's almost impossible for OSHA to promulgate a health standard through the incredibly labor-intensive and time-consuming process we have.

 

Instead, RCFs and all other miscellaneous particulates without specific standards are considered "nuisance dusts," with a PEL of 5 mg/m3 (respirable). As in - cancer is a hell of a nuisance.

 

We try to educate people about it, and we try to put a stop to the worst work practices, but it's an uphill battle. I once saw a company use an RCF gasket to seal a box-annealing furnace, which is a large cylindrical box lofted by a crane and set down over stacked steel coils. The box is filled with an inert gas - usually hydrogen - and heated. The process affects the grain structure of the steel. When the process was complete the hydrogen was evacuated; the box was lifted; and the now-friable RCF gasketing was blown out with compressed air, exposing everyone in the shop.  

 

Michael J. Wright

Director of Health, Safety and Environment

United Steelworkers

5 Gateway Center

Pittsburgh, PA 15222

 

Work (412) 562-2580

Cell     (412) 370-0105

Fax     (412) 562-2584

 

mwright**At_Symbol_Here**usw.org

 

Visit us on the web at www.usw.org

 

 

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