From: "Kennedy, Sheila" <s1kennedy**At_Symbol_Here**>
Subject: Re: [DCHAS-L] Magnesium/Dry Ice Demonstration - fire extinguisher?
Date: Fri, 12 Aug 2016 20:01:13 +0000
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: FA001EE30BA70F4D926117C13DAFFFDF7F44AAA4**At_Symbol_Here**XMAIL-MBX-BH1.AD.UCSD.EDU

Flinn’s website (below) says “Dry sand also works well.” I always suspected that pouring sand on a Mg fire would leave us with a Mg fire burning until it ran out of fuel/oxidizer and a pile of really hot sand.  

Does it work?


Sheila M. Kennedy, C.H.O.

Safety Coordinator | Teaching Laboratories

Chemistry & Biochemistry |University of California, San Diego

9500 Gilman Dr. | La Jolla, CA  92093-0303

(858) 534 – 0221 | MC 0303 | YORK HALL 3150

s1kennedy**At_Symbol_Here** | Student Lab Safety, CHEM Teaching Labs


From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**] On Behalf Of Donald Abramowitz
Sent: Friday, August 12, 2016 10:30 AM
Subject: Re: [DCHAS-L] Magnesium/Dry Ice Demonstration - fire extinguisher?


I concur with having the ABC dry chem extinguisher handy for anything else that ignites.  If you want to have Class D capacity on hand sufficient to handle a coil of magnesium ribbon, Flinn Scientific will sell you a 500 g jar of a Class D fire extinguishing powder for a mere $16.95.  (Catalog No. SE3004) that would be perfect to pour onto the burning ribbon.


Don Abramowitz

Bryn Mawr College

Bryn Mawr, PA

From: DCHAS-L Discussion List <dchas-l**At_Symbol_Here**> on behalf of Debbie M. Decker <dmdecker**At_Symbol_Here**UCDAVIS.EDU>
Sent: Friday, August 12, 2016 12:30:04 PM
Subject: [DCHAS-L] Magnesium/Dry Ice Demonstration - fire extinguisher?




We currently do a magnesium/dry ice demonstration in which about a meter of magnesium ribbon, closely coiled, is put into a well drilled into a block of dry ice.  The ribbon is ignited using an electric lighter and another block of dry ice is slid over the magnesium.  Cue spectacular bright flamage, sparks, and a glowing chunk of dry ice.  One of my personal faves.


We’ve defaulted to having a Class D fire extinguisher on site for this particular demo.  All of the other demos that produce flame can be managed with an ABC dry chem extinguisher.


But the Class D extinguisher is heavy (>75 pounds) and difficult to use.  The fire extinguisher maintenance folks don’t want to maintain it, our on-site fire department would rather we not have it and would probably just let the metal fire burn itself out.  I’ve also done a bit of digging and ABC dry chem will work on a magnesium fire, perhaps not as effectively as the Class D but it’ll work.


I’m inclined to stop hauling this thing around – it’s a back injury/workers comp claim waiting to happen – in favor of having just our ABC dry chem extinguisher on site.


What do you all think?





Debbie M. Decker, CCHO, ACS Fellow

Safety Manager

Department of Chemistry

University of California, Davis

3467 Chemistry Annex

1 Shields Ave.

Davis, CA  95616

(530)754-7964 (T)/(530)304-6728 (cell)



Birkett's hypothesis: "Any chemical reaction

that proceeds smoothly under normal conditions,

can proceed violently in the presence of an idiot."





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.