Efficacy of an amino resin fire retardant


Alexiou, P.N.; Gardner, W.D.; Lind, P.; Butler, D.

Forest Products Journal 36(11-12): 9-15

1986


The inorganic salts which have been commonly used as fire retardants are hygroscopic and readily leac.hed from wood. An amino resin fire retardant is available which is claimed to be leach-resistant and nonhygroscopic. This would render it suitable for use in situations exposed to the weather. To assess its potential within the Australian forest products industry, it was necessary to determine the efficacy of the fire retardant according to Australian standard test methods. Saw boards of Pinus radiata were treated with varying solution strengths of the amino resin. The boards were grouped according to direction of cut and heartwood/sapwood content. For each group, test panels were fabricated using boards of similar resin retention. The early fire. hazard of these panels was then determined by testing according to Australian Standard 1530 Part 3 (4). esin retention was found to be dependent on the d1rect1on of sawing and heartwood/sapwood content. The early fire hazard test results showed that the amino resin was an effective fire retardant in Pinus radiata. Regression analyses indicate that performance could be accur.ately predicted by average resin retention, irrespective of direction of sawing or heartwood/sapwood conten. These regressions should enable industry to determine the resin retention necessary to achieve a specified early fire hazard performance.

Efficacy
of
an
amino
resin
fire
retardant
P.N.
Alexiou
W.D.
Gardner
P.
Lind
D.
Butler
Abstract
The
inorganic
salts
which
have
been
commonly
used
as
fire
retardants
are
hygroscopic
and
readily
leached
from
wood.
An
amino
resin
fire
retardant
is
available
which
is
claimed
to
be
leach-resistant
and
nonhygroscopic.
This
would
render
it
suitable
for
use
in
situations
exposed
to
the
weather.
To
assess
its
poten-
tial
within
the
Australian
forest
products
industry,
it
was
necessary
to
determine
the
efficacy
of
the
fire
re-
tardant
according
to
Australian
standard
test
methods.
Sawn
boards
ofPinus
radiata
were
treated
with
varying
solution
strengths
of
the
amino
resin.
The
boards
were
grouped
according
to
direction
of
cut
and
heartwood/
sapwood
content.
For
each
group,
test
panels
were
fabri-
cated
using
boards
of
similar
resin
retention.
The
early
fire
hazard
of
these
panels
was
then
determined
by
testing
according
to
Australian
Standard
1530,
Part
3
(14).
Resin
retention
was
found
to
be
dependent
on
the
direction
of
sawing
and
heartwood/sapwood
content.
The
early
fire
hazard
test
results
showed
that
the
amino
resin
was
an
effective
fire
retardant
in
Pinus
radiata.
Regression
analyses
indicate
that
performance
could
be
accurately
predicted
by
average
resin
retention,
irre-
spective
of
direction
of
sawing
or
heartwood/sapwood
content.
These
regressions
should
enable
industry
to
determine
the
resin
retention
necessary
to
achieve
a
specified
early
fire
hazard
performance.
The
treatment
of
wood
and
wood
products
with
fire
retardants
has
permitted
their
use
in
architectural
ap-
plications
where
regulations
require
a
specific
fire
per-
formance
(10,
12).
The
inorganic
salts
which
have
been
commonly
used
as
fire
retardants
have
several
disadvantages:
1)
the
salts
are
readily
leached
from
the
wood;
2)
the
occurrence
of
surface
blooming
affects
the
paintability
of
the
treated
wood;
3)
the
salts
may
be
hygroscopic;
4)
corrosion
of
metal
fixtures
in
treated
wood
may
be
increased;
and
5)
treatment
may
affect
the
appearance
of
the
wood
(4,
5,
13).
An
amino
resin
fire
retardant
has
been
developed
by
Eastern
Forest
Products
Laboratory,
Canada,
and
manufactured
by
Iroquois
Chemicals
Limited,
Canada
(under
the
trade
name
of
Irotherm
909-200').
This
am-
ino
resin
is
claimed
to
be
leach-resistant,
nonblooming,
nonhygroscopic,
decay-resistant,
and
to
have
no
effect
on
the
appearance
of
the
wood
(6-9).
These
properties
would
render
wood
treated
with
the
amino
resin
suitable
for
external
use.
The
amino
resin
may
therefore
have
potential
within
the
Aus-
tralian
forest
products
industry
for
use
as
a
fire
re-
tardant
in
situations
exposed
to
the
weather.
To
assess
this
potential,
it
was
necessary
to
determine
the
efficacy
of
this
fire
retardant
when
tested
according
to
Aus-
tralian
standard
test
methods.
The
substrate
chosen
was
Pinus
radiata
D.
Don.
This
species
is
the
most
important
commercial
softwood
grown
in
Australia.
It
is
used
for
general
construction,
flooring,
paneling,
fur-
niture,
joinery,
plywood,
reconstituted
panel
products,
and
paper.
When
it
is
treated
with
preservatives,
it
is
'The
use
of
product
names
in
this
publication
does
not
con-
stitute
an
official
endorsement
or
approval
by
the
Forestry
Commission
of
N.S.W.
to
the
exclusion
of
comparable
products.
The
authors
are,
respectively,
Research
Officers
and
Bio-
metrician,
Forestry
Commission
of
New
South
Wales,
P.O.
Box
100,
Beecroft,
N.S.W.,
Australia
2119;
and
Chemist,
Hitchins
Australia
Pty.
Ltd.,
9
Sirius
Rd.,
Lane
Cove,
N.S.W.,
Australia
2066.
The
authors
wish
to
thank
Hitchins
Australia
Pty.
Ltd.
for
their
cooperation
in
treating
the
test
material
with
Pyrogard
H,
and
G.
Baxter,
Technical
Officer,
Forestry
Commission
of
N.S.W.,
for
his
assistance
during
the
testing.
This
paper
was
received
for
publication
in
October
1985.
c
Forest
Products
Research
Society
1986.
Forest
Prod.
J.
36(11/12):9-15.
FOREST
PRODUCTS
JOURNAL
Vol.
36.
No.
11/12
9
used
for
siding,
decking,
external
trim,
poles,
piles,
fencing,
and
sleepers
(2).
The
resin
is
available
in
Aus-
tralia
with
a
proprietary
preservative
additive
under
the
trade
name
of
Pyrogard
H.'
To
assess
the
fire
retardant
properties
of
Pyrogard
H,
it
was
necessary
to
determine:
1.
The
treatability
of
Pinus
radiata
with
the
resin
and
the
influence
of
the
direction
of
sawing
and
heartwood/sapwood
content
on
treatability;
2.
The
efficacy
of
the
resin
as
a
fire
retardant
when
applied
to
Pinus
radiata,
and
tested
to
Australian
Stan-
dard
1530,
Part
3
(AS1530)
(14).
The
AS1530
test
was
developed
from
corner-wall-
burn
experiments
to
grade
cellulosic
wallboards
accord-
ing
to
their
tendency
to
ignite
and
spread
flame
verti-
cally.
A
test
specimen
is
held
in
a
vertical
configuration
in
a
plane
parallel
to
a
radiant
heater.
The
specimen
is
moved
toward
the
heater
in
steps
over
a
period
of
20
minutes
or
until
ignition
(induced
by
a
pilot
flame)
occurs.
A
typical
test
apparatus
is
shown
in
Figure
1.
The
increasing
intensity
of
radiant
heat
on
the
test
panel
(Fig.
2)
simulates
that
which
could
be
experienced
during
the
early
development
of
a
building
fire
(3).
Combustible
volatiles
from
the
test
specimen
are
ig-
nited
by
a
pilot
flame
set
close
to
the
area
of
the
test
specimen
which
is
subject
to
the
maximum
intensity
of
radiant
heat.
Test
specimens
are
freely
ventilated.
The
early
burning
properties
of
a
material
when
determined
by
this
test
are
described
by
four
reaction-
to-fire
parameters:
1)
time-to-ignition;
2)
heat-evolved
integral;
3)
spread
time;
and
4)
optical
density
of
smoke.
These
parameters
are
used
to
derive
the
respective
early
fire
hazard
indexes.
It
is
important
to
note
that
these
indexes
are
interrelated,
because
they
are
ob-
tained
as
a
result
of
a
single
fire
test.
Ignitability
index
The
ignitability
index
relates
to
the
time
taken
for
the
volatiles
from
the
test
specimens,
irradiated
at
increasing
intensity,
to
form
an
ignitable
gas
mixture
and
be
ignited
by
a
small
flame.
It
is
rated
on
an
arithmetic
scale
of
0
to
10.
The
index
is
zero
if
such
ignition
does
not
occur
under
the
maximum
impressed
radiation
during
the
test.
Heat-evolved
index
The
heat-evolved
index,
rated
on
an
arithmetic
scale
of
0
to
20,
relates
to
the
total
amount
of
radiant
energy
released
by
a
burning
material.
The
higher
the
index,
the
more
likely
is
the
fire
involvement
of
nearly
combustible
materials.
Spread-of-flame
index
This
index
was
developed
from
the
observed
cor-
relation
between
the
rate
of
energy
released
and
the
time
taken
for
flames
to
spread
from
the
floor
to
the
ceiling
in
the
corner-burn
tests
from
which
this
Aus-
tralian
Standard
was
developed
(3).
The
index
is
rated
on
an
arithmetic
scale
of
0
to
10
according
to
the
rate
of
energy
released
by
the
burning
test
specimens.
An
index
of
10
indicates
that
the
material
could
be
expected
to
cause
flames
to
reach
a
2.7-m-high
ceiling
within
10
seconds
of
ignition;
an
index
of
zero
means
that
the
material
will
not
cause
flames
to
reach
the
ceiling
within
4-1/2
minutes
of
ignition.
25
Light
source
Steel
stack
---
-Photoelectric
cell
„.-Smoke
hood
20
10
Buffers
Radiometer
-
Shield
Radiant
panel
20
Pilot
flame
Specimen
15
0
5
Steel
strip
covering
slot
in
table
10
Time
(min.)
Mobile
table
Figure
1.
Typical
apparatus
for
early
fire
hazard
test
(14).
Figure
2.
Plot
of
heat
energy
input
vs.
time
to
ignition
for
the
early
fire
hazard
test
(11).
10
NOVEMBER/DECEMBER
1986
Smoke-developed
index
The
smoke-developed
index,
rated
on
a
geometric
scale
of
0
to
10,
relates
to
the
optical
density
of
smoke
produced
under
the
conditions
of
the
standard
test.
The
higher
the
index,
the
greater
the
obscuration
produced
by
the
smoke.
The
decay
and
leach
resistance
of
the
resin
when
impregnated
in
Pinus
radiata
will
be
the
subject
of
a
separate
report.
Materials
1.
Kiln-dried
Pinus
radiata
was
obtained
from
Bathurst
Forestry
Region,
New
South
Wales.
2.
Pyrogard
H
consists
of
Irotherm
909-200,
an
amino
resin
having
a
basic
formula
of
urea:dicyandiamide:formaldehyde:phosphoric
acid
(1:3:8:4),
and
a
proprietary
preservative
additive.
Test
panel
preparation
AS1530
requires
test
specimens
to
measure
600
by
450
mm
and
be
of
normal
thickness.
They
should
be
prepared
to
closely
represent
the
material
or
product
in
the
use
for
which
it
is
intended
(14).
Panels
were
pre-
pared
to
represent
siding
and
paneling
as
described
in
the
following
sections.
Selection
of
timber
The
Pinus
radiata
boards
were
graded
into
six
groups,
depending
upon
the
direction
of
sawing
and
sapwood/heartwood
content,
as
follows:
I
-
flatsawn
heartwood
II
-
quartersawn
heartwood
III
-
flatsawn
sapwood
IV
-
quartersawn
sapwood
V
-
mixed
heartwood/sapwood,
quarter-
sawn
VI
-
mixed
heartwood/sapwood,
flatsawn
Test
boards
600
by
90
by
12
mm
were
machined
from
boards
allotted
to
each
of
the
six
groups.
Test
boards
having
knots
or
resin
pockets
within
the
central
1/3
of
the
exposed
face
were
discarded.
Treatment
procedure
Before
treatment,
each
board
was
weighed
and
its
moisture
content
(MC)
determined
by
electric
resis-
tance
meter.
The
sample
boards
were
randomly
as-
signed
to
a
position
in
a
vertical
cylindrical
vessel,
750
by
600
mm.
A
vacuum
of
-
98
kPa
was
drawn
and
the
cylinder
flooded
under
this
vacuum
with
various
solutions
in
water
of
Pyrogard
H.
The
following
solutions
were
used:
1.
20
percent
(w/w)
Irotherm
909-200
plus
0.33
percent
(w/w)
of
the
preservative
additive;
2.
12
percent
(w/w)
Irotherm
909-200
plus
0.3
per-
cent
(w/w)
preservative;
3.
4
percent
(w/w)
Irotherm
909-200
plus
0.22
per-
cent
(w/w)
preservative.
After
flooding,
the
vacuum
was
released
to
atmo-
sphere.
This
condition
was
maintained
for
2
hours.
The
solution
was
then
pumped
out,
and
a
final
vacuum
of
-
98
kPa
applied.
After
treatment,
the
boards
were
heated
at
70°C
until
the
MC
of
the
boards
had
been
reduced
to
10
to
12
TABLE
1.
-
Mean
resin
retention
for
each
group
in
each
treatment.
Treatment
level
Test
group
No.
of
boards
Mean
retention
Standard
deviation
(kg/m')
20%
I
16
38.2
22.4
II
18
47.6
24.4
III
33
136.8
16.5
IV
33
123.8
33.0
V
33
68.8
27.2
VI
18
88.8
41.6
12%
III
50
82.7
15.5
IV
34
67.2
27.1
V
110
54.0
17.4
4%
III
30
23.0
3.7
percent,
and
the
resin
was
then
cured
by
raising
the
temperature
to
105°C
for
16
hours.
The
boards
were
then
cooled
over
silica
gel,
their
ovendried
weight
was
measured,
and
the
resin
re-
tention
of
each
board
was
calculated.
The
boards
were
then
allowed
to
return
to
equilibrium
moisture
content
(EMC)
(10-15%).
Fabrication
of
panels
Initially,
panels
were
fabricated
from
untreated
boards
and
from
boards
treated
with
a
20
percent
solu-
tion
of
resin.
For
each
treatment,
it
was
intended
that
6
panels
(600
by
450
mm)
each
composed
of
5
boards,
be
prepared
for
each
timber
group.
Due
to
regrading
prob-
lems,
however,
it
was
only
possible
to
prepare
three
untreated
and
three
treated
panels
for
groups
I,
II,
and
VI.
The
remaining
groups
were
allotted
6
panels
each.
Two
support
braces
(400
by
45
by
12
mm)
of
the
same
timber
group
were
nailed
across
the
rear
of
the
boards
in
each
panel.
After
results
for
these
panels
were
known,
further
panels
were
fabricated
from
boards
treated
with
a
12
percent
solution
of
resin
as
follows:
5
panels
from
timber
group
III,
3
panels
from
group
IV,
and
10
panels
from
group
V.
Subsequently,
an
additional
6
panels
com-
prised
of
group
III
boards
treated
with
a
4
percent
solution
of
resin
were
also
fabricated.
Test
method
At
each
treatment
level
and
for
each
timber
group,
statistical
analyses
were
performed
to
identify
the
treatability
of
the
timber
groups
and
to
determine
the
effect
of
heartwood
percentage
on
resin
retention.
As
specified
in
the
standard,
the
test
panels
were
conditioned
for
7
days
in
an
atmosphere
having
a
rela-
tive
humidity
of
65
percent
±
5
percent
and
a
tempera-
ture
of
20°C
±
2°C.
The
early
burning
properties
of
the
panels
were
then
tested
according
to
AS1530
(14).
Statistical
analyses
were
performed
to
determine
the
relationship
between
resin
retention
and
per-
formance
during
early
fire
hazard
testing.
Results
and
discussion
Treatability
The
mean
retention
for
each
timber
group
in
each
treatment
is
given
in
Table
1.
The
results
indicate
that
the
sapwood
(groups
III
and
IV)
ofPinus
radiata
is
much
more
efficiently
treated
than
the
heartwood
(groups
I
and
II).
This
is
supported
by
the
results
for
groups
V
and
FOREST
PRODUCTS
JOURNAL
Vol.
36,
No.
11/12
11
y=
100.487
-
0.8359x
---
95%
confidence
limits
r
or
0.8786
p<
0.001
-
y
=
143.939
-
1.2309x
95%
confidence
limits
r
0.8632
p<
0.02
.
25
50
75
100
Heartwood
content
(%)
70
;1
5
35
140
105-
80
.4
I
T
!
40
160
12
25
50
75
100
Heartwood
content
(%)
Figure
3a.
Retention
vs.
heartwood
content
(20%
treatment
group
V).
VI,
which
lie
between
those
for
heartwood
alone
(I
and
II)
and
sapwood
alone
(III
and
IV).
Also,
the
flatsawn
sapwood
(III)
treated
more
regularly
than
the
quarter-
sawn
sapwood
(IV),
as
evidenced
by
the
higher
mean
retention
and
smaller
standard
deviation.
For
the
12
percent
treatment,
the
mean
retention
of
flatsawn
sap-
wood
was
significantly
higher
at
the
95
percent
prob-
ability
level
than
that
of
quartersawn
sapwood.
For
the
20
percent
treatment,
the
mean
retention
of
flatsawn
sapwood
was
on
the
borderline
of
being
significantly
higher
than
that
of
quartersawn
sapwood.
Because
flatsawn
sapwood
of
Pinus
radiata
achieved
both
the
highest
retentions
and
the
narrowest
range
of
retentions,
it
appears
to
be
the
most
suitable
substrate
for
experiments
in
which
repeatability
of
treatment
is
important.
Its
highly
consistent
treat-
ability
renders
it
ideal
as
a
substrate
for
evaluating
the
treatability
of
Pinus
radiata
with
new
processes
or
chemicals,
and
the
efficacy
of
preservatives
or
fire
re-
tardant
chemicals.
The
regression
lines
of
resin
retention
versus
the
percentage
of
heartwood
are
shown
for
the
20
percent
treatment
of
timber
groups
V
and
VI
(Figs.
3a
and
3b),
and
for
the
12
percent
treatment
of
timber
group
V
(Fig.
3c).
Also
indicated
are
the
95
percent
confidence
limits
for
the
average
retention
which
would
be
expected
upon
treating
a
batch
of
boards
at
each
percentage
heartwood
content.
These
results
indicate
that
the
amount
of
Pyrogard
H
retained
is
inversely
related
to
the
percentage
of
heartwood
contained
in
the
timber,
as
expected.
They
also
indicate
that
where
a
batch
of
boards
with
similar
percentage
heartwood
contents
is
treated,
it
is
possible
to
estimate
the
average
retention
of
that
batch
within
the
given
confidence
limits.
However,
because
of
the
variable
treatability
of
timber
group
V
and
the
small
number
of
points
plotted,
the
confidence
limits
in
Figure
3a
are
very
wide.
Early
fire
hazard
properties
The
reaction
to
fire
parameters
for
all
timber
groups
was
plotted
against
average
resin
retentions,
and
are
shown
in
Figures
4a,
4b,
and
4c.
Flame
spread
Figure
3b.
Retention
vs.
heartwood
content
(20%
treatment
group
VI).
y=
70.233
-
0.5425x
---
95%
confider+ce
limits
r•
0.547
p<
0.001
!
A
t
4_
2
t
2
25
50
75
1.0
Heartwood
content
(%)
Figure
3c.
Retention
vs.
heartwood
content
(12%
treatment
group
V).
time
was
not
plotted
because
only
a
small
number
of
panels
achieved
spread
times
of
less
than
4.5
minutes
(1).
For
all
timber
groups,
panels
that
had
retention
levels
of
>
40
kg/m
3
had
delayed
times
to
ignition
and
had
spread
times
greater
than
4.5
minutes.
Spread
times
greater
than
4.5
minutes
yield
spread-of-flame
indexes
of
zero.
Results
have
been
expressed
as
early
fire
hazard
indexes
for
flatsawn
sapwood
(group
III)
in
Table
2.
Effect
of
resin
retention
on
reaction
to
fire
parameters
Trends
were
evident
for
an
effect
of
resin
retention
on
the
time-to-ignition
and
the
heat-evolved
integral.
Linear,
logarithmic,
and
quadratic
regressions
were
tested
for
goodness-of-fit.
No
trends
were
apparent
in
the
scattergram
of
optical
density
of
smoke
developed
(Fig.
4c),
except
that
optical
density
increases
markedly
with
average
resin
retentions
greater
than
about
40
kg/m
3
,
probably
because
retardance
of
ignition
begins
at
this
level.
Time-to-ignition.—The
regression
equations
with
the
best
fit
for
all
treatment
levels,
including
controls,
12
NOVEMBER/DECEMBER
1986
14
7
8
3
15
5
7
4
11
0
0
6
0
0
0
5
nil
4%
12%°
20%
(kg/m
3
)
nil
22.9
86.2
137.5
. .
2
0
rn
i
0
5
are
shown
in
Table
3.
From
Table
3
it
can
be
seen
that
the
addition
of
data
for
heartwood
and
mixed
heartwood/sapwood
to
the
data
for
sapwood,
reduces
the
amount
of
variation
explained
by
the
regression
by
only
a
few
percent.
These
results
imply
that
panels
con-
structed
with
mixed
heartwood/sapwood
boards
per-
formed
as
if
the
higher
sapwood
retention
of
each
board
was
averaged
over
the
whole
board.
The
equation
for
all
timber
groups
combined,
shown
in
Figure
4a,
has
the
greatest
application
for
industry.
The
time-to-ignition
of
treated
Pinus
radiata
boards,
irrespective
of
direction
of
cut
or
heartwood/
sapwood
content,
could
be
accurately
predicted
by
TABLE
2.
Average
results
for
flatsawn
sapwood
(group
III).
Solution
strength
Average
resin
(w/w)
retention
II°
HE'
SF`
SD
d
°II
=
Ignitability
index.
b
HE
=
Heat-evolved
index.
'SF
=
Spread-of-flame
index.
d
SD
=
Smoke-developed
index.
'The
average
early
fire
hazard
indexes
for
flatsawn
sapwood
treated
with
the
12%
(w/w)
solution
are
based
on
the
results
from
five
test
panels
instead
of
the
usual
six.
Group
I
••
O
Group
II
Group
III
/
o
Group
IV
Group
V
A
Group
VI
measuring
retention.
From
Figure
4a,
it
is
apparent
that
the
resin
does
not
retard
ignition
until
the
average
retention
becomes
greater
than
about
40
kg/m
3
.
It
is
interesting
to
note
the
marked
increase
in
optical
den-
sity
of
smoke
at
the
same
resin
retention
(Fig.
4c).
At
retentions
lower
than
40
kg/m',
ignitability
is
increased
slightly.
270
y=
201.69
-
3.6409R+
0.02698R
2
-
7.61409
x
10
5
R
3
---
95%
confidence
limits
r
0.9294
p<
0.001
225
180
\
\
\I
0 0
`,
0
0
Ins
40
80
120
160
Average
retention
(kg/m
3
)
Figure
4b.
Heat-evolved
integral
vs.
average
retention
for
all
timber
groups.
Early
fire
hazard
indexes
Group
I
o
Group
II
Group
III
a
Group
IV
Group
V
o
Group
VI
4
E
_
-*
P
135
90
(I;
c
c
°
m
45
y=
5.449
-
0.0455R+
0.001R
2
---
95%
confidence
limits
r
=
0.9028
P
<
0.001
/
° /
A
/
.
/
SO
a
0
to/
.35
Group
I
o
Group
II
,
3
Group
III
.
o
Group
IV
E
Group
V
.25
4
Group
VI
"fo
i
.2
0
0
.15
a
Z's
,3
mi
.1
.•
0
.05
/
/
/
a
0
0
a
•c•
0
0
40
80
20
Average
retention
(kg
,
m
3
)
40
8•
1
Average
retention
(kg/m
3
)
1:
0
0
Figure
4a.
Time
to
ignition
vs.
average
retention
for
all
timber
groups.
Figure
4c.
Optical
density
of
smoke
developed
vs.
average
retention
for
all
timber
groups.
13
FOREST
PRODUCTS
JOURNAL
Vol.
36,
No.
11/12
heartwood/sapwood
boards,
not
on
its
distribution
through
these
boards;
3.
It
is
possible
to
predict
the
average
time-to-
ignition
and
heat-evolved
integral
of
all
Pinus
radiata
boards,
irrespective
of
direction
of
sawing
or
heartwood/
sapwood
content,
by
measuring
resin
retention.
Con-
versely,
the
retention
needed
to
achieve
a
specific
time-
to-ignition
or
heat-evolved
integral
can
be
accurately
determined.
4.
For
resin
retention
levels
at
which
time
to
ig-
nition
is
retarded
(about
40
kg/m
3
),
the
spread-of-flame
index
of
Pinus
radiata
boards,
irrespective
of
direction
of
sawing
or
heartwood/sapwood
content,
will
be
zero.
Literature
cited
1.
ALEmou,
P.N.,
W.D.
GARDNER,
P.
LIND,
AND
D.
BUTLER,
1983.
Evaluation
of
Pyrogard
H
as
a
fire
retardant.
Forestry
Comm.
of
N.S.W.
Wood
Tech.
&
Forest
Res.
Div.
Unpublished
Rept.
No.
907.
28
pp.
2.
BOOTLE,
K.R.
1983.
Wood
in
Australia:
Types,
Properties
and
Uses.
McGraw-Hill
Book
Co.,
Sydney.
pp.
333-336.
3.
FERRIS,
J.E.
1955.
Fire
hazards
of
combustible
wall
boards.
Dept.
of
Works.
Commonwealth
Exper.
Build.
Sta.
Special
Rept.
No.
18.
4.
GARDNER,
R.E.
1965.
Auxiliary
properties
of
fire-retardant
treated
wood.
Forest
Prod.
J.
15(9):
365-368.
5.
GOLDSTEIN,
I.S.
AND
W.A.
DREHER,
1961.
Non-hygroscopic
fire
retardant
treatment
for
wood.
Forest
Prod.
J.
11(5):235-237.
6.
JUNEJA,
S.C.
1972.
Stable
and
leach-resistant
fire
retardants
for
wood.
Forest
Prod.
J.
22(6):17-23.
7.
and
L.R.
RICHARDSON.
1974.
Versatile
fire
retardants
from
amino
resins.
Forest
Prod.
J.
24(5):19-23.
8.
and
J.K.
SHIELDS.
1973.
Increased
fungal
resistance
of
wood
treated
with
modified
urea-based
fire-retardant
resins.
Forest
Prod.
J.
23(5):47-49.
9.
KING,
F.W.
AND
S.C.
JUNEJA.
1974.
A
new
fire-retardant
treatment
for
western
redcedar
shingles.
Forest
Prod.
J.
24(2):18-23.
10.
LAWSON,
D.I.
1959.
Wood
and
fire
research.
J.
Insti.
Wood
Sci.
4(4):3-13.
11.
MOULEN,
A.W.,
K.G.
MARTIN,
S.J.
GRUBITS,
AND
V.P.
DOWLING.
1980.
The
early
fire
behaviour
of
combustible
wall
lining
materials.
Fire
and
Materials
4(4):165-172.
12.
MYERS,
G.C.
AND
C.A.
HOLMES.
1975.
Fire-retardant
treatment
for
dry-formed
hardboard.
Forest
Prod.
J.
25(1):20-28.
13.
SHUNK,
B.H.
1977.
The
role
of
fire-retardant
treated
wood
in
the
protection
of
life
and
property.
Wood
and
Fiber
9(2):89-95.
14.
STANDARDS
ASSOCIATION
OF
AUSTRALIA.
1976.
AS
1530.
Methods
for
fire
tests
on
building
materials
and
structures.
Part
3.
Test
for
early
fire
hazard
properties
of
materials.
Sydney.
12
pp.
Timber
frame
homes
will
be
demonstrated
in
the
United
Kingdom
The
U.S.
Department
of
Agriculture
has
announced
an
agreement
between
its
Foreign
Agricultural
Service
(FAS)
and
the
American
Plywood
Association
(APA)
to
develop
a
timber
frame
home
demonstration
project
in
the
United
Kingdom
in
1987,
in
cooperation
with
a
leading
U.K.
homebuilder.
Agriculture
Secretary
Richard
E.
Lyng
said
that
the
$653,000
program
will
help
expand
exports
of
U.S.
wood
products
to
the
United
Kingdom
and
at
the
same
time
help
to
counter
the
continuing
negative
public
perception
of
wood
frame
construction
in
Britain.
Timber
frame's
share
of
the
British
housing
market
has
fallen
from
20
percent
in
1983
to
around
7
percent
currently,
largely
as
a
result
of
a
1983
television
program
that
singled
out
incorrect
applications
of
wood
products.
Some
recovery
from
the
impact
of
this
program
had
been
recorded.
However,
yet
another
recent
TV
program
may
cause
further
market
erosion
with
a
distorted
presentation
on
fires
in
wood
construction.
In
its
new
cooperative
project
with
FAS,
APA
will
join
with
one
of
the
largest
U.K.
homebuilding
companies
and
a
major
British
consumer
magazine
to
build
a
"Quality
Home
Lane"
of
wood
frame
homes
in
a
variety
of
formats
expressly
designed
Association
will
help
assure
maximum
for
the
British
market.
use
of
U.S.
wood
products.
The
homes
will
be
similar
to
"Street
"This
project
will
show
British
of
Dreams"
projects
in
the
United
homeowners,
builders,
and
designers
States,
and
will
be
demonstrated
to
that
the
well-constructed
timber
frame
the
public
for
an
extended
period.
A
home
is
cost-effective,
safe,
and
concentrated
advertising,
publicity,
durable,"
said
Dennis
Hardman,
and
builder
seminar
program
will
director,
APA
Information
Services
cover
builder,
lender,
and
consumer
Division.
Funds
for
the
program
will
audiences.
Participation
of
the
be
provided
by
the
Department
of
Southern
Forest
Products
Association
Agriculture
under
the
Food
Security
and
Western
Wood
Products
Act
of
1985.
Conference
Announcement
and
Call
for
Papers
1988
International
Conference
on
Timber
Engineering
Washington
State
University,
in
cooperation
with
the
National
Science
Foundation,
the
United
States
Department
of
Agriculture,
the
American
Society
of
Civil
Engineers,
the
Forest
Products
Research
Society,
the
Society
of
Wood
Science
and
Technology,
and
several
other
organizations
is
sponsoring
an
International
Conference
on
Timber
Engineering.
The
conference
will
be
held
on
September
19
to
22,
1988
in
Seattle,
Wash.
This
conference
will
present
recent
developments
and
innovations
in
design,
construction,
research,
and
materials.
It
will
promote
interaction
among
design
engineers,
contractors,
researchers,
and
scientists,
and
will
communicate
the
current
world
state-of-the-art
of
timber
engineering.
Over
30
sessions
are
scheduled
to
cover
the
various
aspects
of
timber
engineering.
Persons
wishing
to
present
papers
at
this
conference
should
submit
four
copies
of
their
abstract
on
or
before
June
30,
1987
to
Rafik
Itani,
Conference
Chairman,
Dept.
of
Civil
and
Environmental
Engineering,
Washington
State
Univ.,
Pullman,
WA
99164-2914,
U.S.A.
Abstracts
should
be
typewritten
and
not
more
than
500
words
in
length.
All
abstracts
will
be
reviewed
and
authors
will
be
notified
by
August
31,
1987.
Prospective
authors
may
submit
more
than
one
abstract.
Complete
papers
of
accepted
abstracts
will
be
due
May
31,
1988.
All
papers
will
be
reviewed
prior
to
their
publication
in
the
conference
proceedings.
15
FOREST
PRODUCTS
JOURNAL
Vol.
36,
No.
11/12