Date: Tue, 19 Jan 2010 20:18:00 -0500
Reply-To: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: Peter Zavon <pzavon**At_Symbol_Here**ROCHESTER.RR.COM>
Subject: Re: Flammable gas in a quartz tube/electric furnace assembly
In-Reply-To: <8EDCBF65F98F1C40BCC235C034B3ED3704D7A1BA7C**At_Symbol_Here**capsm01.CAPSD.USC.EDU>

In my opinion, placing large or bulky equipment in a vertical laminar flow hood is likely to degrade hood performance (the more so if hot equipment is involved) and is a misuse of expensive equipment more properly used for other purposes.  In any case, such  a hood is not a blast shield and will not eliminate any need you may have for blast protection.  There is a reason canopy hoods are preferred for ventilating hot equipment.

Peter Zavon, CIH
Penfield, NY


From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**] On Behalf Of Alfred Bouziane
Sent: Tuesday, January 19, 2010 6:16 PM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: [DCHAS-L] Flammable gas in a quartz tube/electric furnace assembly

Hello everyone:

A researcher here plans to continuously flow 100 % flammable gas (methane, ethylene, hydrogen, or mixture) at 1 cfm through a quartz tube/electric furnace assembly that is heated to 800 degrees C (exceeds the auto-ignition temperature of the gases). The researcher intends to have four (4) of these units (~18”h x 24”d x 60” w) in the lab;  at least two units will be active throughout the day.

The discussion centers on where to safely set up and operate them. The researcher proposed mounting the units on open benchtops (two per benchtop) to accommodate their size and facilitate use (the gases would be piped to the units via stainless steel tubing from an adjacent gas room). Though seemingly practical, I feel this would require considerable $$ investment in engineering controls (canopy hood, blast shields, etc.) to adequately protect the research staff from potential mishaps (gas leaks, explosions). My thought is to mount the assembly in the lab’s wet process hood (vertical laminar flow) and lower the sash during operation. Though not ideal, it would reduce the potential of these mishaps. NOTE: There are only two available process hoods in the lab, hence, only two assemblies would be up and running (not a bad thing in my opinion).

Here are my questions:

1.       Has anyone tackled a problem like this in the past?  How was it resolved?

2.       What other safeguards do you recommend?

I welcome your collective input. Thank you in advance for your help.

         & nbsp;                                                 ;    

Best regards,

Alfred M. Bouziane

Project Manager

Environmental Health and Safety

University of Southern California index.cfm

Previous post   |  Top of Page   |   Next post

The content of this page reflects the personal opinion(s) of the author(s) only, not the American Chemical Society, ILPI, Safety Emporium, or any other party. Use of any information on this page is at the reader's own risk. Unauthorized reproduction of these materials is prohibited. Send questions/comments about the archive to
The maintenance and hosting of the DCHAS-L archive is provided through the generous support of Safety Emporium.