photo to enlarge
discussion of the fire safety in using foam as a construction
material for model railroad layouts and for scenery bases, we
testing to get to the bottom of the truth. Yes, we first reviewed
the manufacturers ratings and other facts and opionions that
others had posted, but we wanted to see our own results.
to perform a series of tests on two types of foam used for scenery
foam - commonly called "bead board" because
it is made of expanded foam beads. This is the type of foam
that is used for packaging to protect products.
foam & blue
To simulate different scenarios, we came up with four different
tests which include:
Electrical overheating and sparks
The lit match test
Dancing flames beneath
Flames living on the edge
All contents of this page and the tests described herein
were conducted only for our own interests and not for
in the use or not use of any product mentioned or used in these
tests. Therefore this information on this webpage should be viewed
for entertainment purposes only. Do not perform these
tests at home.
Overheating and Sparks
simulate an overheating electrical device that would cause
sparks and a possible fire, we used steel wool and a 6 volt lantern
battery with a couple of test lead wires. we set a clump of
wool the size of a cotton ball onto each piece of foam and
teased it with the test leads from the lantern battery. Each
steel wool formed a hole in the foam as it heated and melted
its way into the foam. No flame or continual smoldering occured
on any of the foam with this method. The
hole in the white foam melted much faster than the more dense
The Lit Match Test
This test was to see what would happen if a lit
match was laid on top of the foam material.
foam - The lit match ignited the foam and
it did not stop burning until the entire piece of foam
consumed. The smoke was black and thick. After the
foam was completely consumed (in about 3 minutes) then
puddles of melted foam continued to burn with the same
black smoke for approximately 10 minutes until they
were all gone. The white foam ignited as easily as
a wad of
newspaper. The piece of test foam was approximately
10" x 6" x 1/2". The photo to the right shows all that
was left after the piece of foam was completely consumed.
and blue foam - These foams melted with the
heat of the flame from the match, but did not ignite
in flame. As you can see from the photo, the matches
are completely burned from one end to the next. In executing
this experiment several times, never did the foam want
to burn, but only melt away from the flame to avoid it.
Basically if the matches had burned longer, the foam
would have continued to melt until the match either burned
through the bottom and dropped, or sat upon whatever
surface was beneath the foam. The pink and blue foam
smell like burning plastic as they melt, but there was
not really much smoke from the melting. Please notice the matches
still in the holes in the foam. The hole in the middle of the
blue piece in the photo is the remnants of the burning steel
wool from test #1.
photos to enlarge
Dancing Flames Beneath
This test shows the effects of a concentrated open flame beneath foam. For
this test we placed a candle underneath the samples of foam with the flame
in direct contact with the foam.
foam - This material had another miserable failure
as it just burst into flames and was totally engulfed
in about 20 seconds. This also ended with thick black
smoke coming from long lasting burning puddles of melted
foam. Again, nothing was left of the foam.
and blue foam - We were curious if a concentrated
open flame would cause this foam to catch on fire. It did
not. The heat of the flame simply melted away a hole above
the flame until finally the hole was large enough that
it went all the way throught the 2" thick foam. After
the hole expanded to about 2cm (3/4"), the hole stopped
expanding because enough heat was able to escape so the
foam stopped melting.
hole in foam
Flames Living on the Edge
An extreme test of flamability. This is the "let's try hard
to make it burn test"
by placing an open flame from a candle to the edge of the foam samples.
foam - Of course this material had another miserable failure
as it was totally engulfed in flames in about 20 seconds. This also
ended with the previous thick black smoke coming from long lasting
burning puddles of melted foam. We obviously have not had to try
very hard to make this material burn and give off its noxious smoke
and blue foam - This test amazed us at how the foam actually
did not want to stay aflame by itself. We were able
to get the candle to ignite the foam edge, but upon taking away the
on the foam would extinguish themselves. This is true even when the
foam was angled so that the flames had an optimal upward
direction to try to keep the flames going. As you can see from the
photo, we were able to burn away the corner
foam being burned away was only the result of our catching the material
on fire 20 times with the open candle
flame. Each time, the
White foam used for packing is as flamable as wads of newspaper,
and produces a very thick black noxious smoke. Pink
and blue construction foam easily melts, but it does
not really like to burn. It
basically tries to melt away from
any threatening heat. The melting almost works like a safety
feature. When this foam comes in close proximity or contact
with threatening heat, it simply melts away from the area
of the heat so that the heat is no longer a threat. Even
if it is ignited into flames, without some other flamable
material, it extinguished the flames on its own in our
tests. The pink and blue foam also do not generate the
black smoke like the white packing foam produced.
observing these tests, we actually feel safer about using
the pink and blue construction foam now than we did before.
We also feel that we will rethink ever using the white packing
foam for filler in our model landscaping. From our tests,
we theorize that if an electrical apparatus was attached
to the bottom of a layout made of construction foam it would
melt the surrounding foam until the weight of the apparatus
would cause it to fall and either hit the floor or hang from
about those natural stick and weed tree armatures...that is a whole
other set of tests.
note that these tests were only performed on bare foam. Once
scenic elements such as turf, trees, structures, subroadbed,
track, artificial water, and trains are added, the results
All contents of this page and the tests described herein
were conducted only for our own interests and not for advising
anyone in the use or not to use of any product mentioned
or used in these tests. Therefore this information on this
should be viewed for entertainment purposes only. Do not
perform these tests at home.