From: Paul Doherty (pauld@exploratorium.edu)
Date: Thu Sep 23 2004 - 16:50:48 PDT
Message-Id: <l03110776bd7911b16f67@[192.168.112.30]> Date: Thu, 23 Sep 2004 16:50:48 -0700 From: Paul Doherty <pauld@exploratorium.edu> Subject: fire piston warning
From the PIRA list serve via Paul D
Hi all,
I just had a pretty scary thing happen.
For the past few years I've done the demonstration where a small piece
of toilet paper is ignited in a glass tube by compressing the air in the
tube by pushing rapidly down on a tight fitting piston. "Science Kit
Boreal Labs" is one supplier of such apparatus
http://www.sciencekit.com/search.asp?t=ss&ss=fire+piston&c=0&x=14&y=6
as is Frey Scientific
https://www.freyscientific.com/ordering/ECommerce;jsessionid=7F76EB418312823FA94
9E29FE33DE09B
I'm sure there are others.
On humid days I had trouble getting the tissue paper to light, so I
mentioned this to some colleagues at an NSTA meeting and one, who shall
remain nameless, suggested that instead of using tissue paper, I use
magician's flash paper, as it ignites more easily. I tried this a few
minutes ago with one of my lab groups watching. I only used about a
square centimeter of paper, two at most. The glass tube exploded, as did
the plastic "safety" tube surrounding it. Two of my students received
minor cuts from flying glass shards, very minor cuts and both students
were really good about it, but it scared them and me. More important, it
could have been a whole lot worse, (let's hear it for lab safety
goggles) so, my advise is
NEVER USE FLASH PAPER IN A FIRE PISTON,
cheers,
David
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