Safely
SPEAKING Polyurethane – “solid gasoline”
BY DOUG STEWART
F
IRE hazard of unprotected spray-on foam
insulations – polyurethane
Plastics used for insulation have an inherent fire risk dealers
should be aware of if they are looking to upgrade the insulation level in an
existing building or purchase property with this type of insulation. Plastic
insulation may be found as board stock (commonly referred to as bead
board) or as spray-on insulation. The spray-on type of foam insulation
commonly used is polyurethane. Over the years, this type of insulation
has become know as “solid gasoline” in the insurance industry.
Why is this type of insulation so popular?
The insulating effectiveness of foam plastic insulation is often considered to be superior to other types of insulations. The “R” rating is
higher and, with less bulk than other insulation, it’s more effective and
often easier to apply.
How to recognize when the insulation is spray-on
foam plastic – polyurethane
If a dealer is considering purchasing a property, recognizing polyurethane insulation can be important in the purchase decision. There is
a sponge-like appearance to polyurethane insulation. The insulation
is formed when chemicals are mixed together that expand, causing
small cellular air pockets similar in appearance to sponge. These small
cells, while sponge-like in appearance, are very dense. A fingernail can
mark the urethane but it does not spring back into shape once force is
removed. There are other spray-on insulations but most of these are
fibrous. The polyurethane is often orange/yellow in colour.
What causes spray-on polyurethane to be so
dangerous?
When heated, polyurethane gives off a highly combustible gas. This
gas will cause an instant flashover, putting life and property in danger.
The thick, black smoke obscures vision and causes asphyxiation.
Once a polyurethane fire is started, there is usually a total loss of
the property.
Know the current building code
The current building code calls for exposed polyurethane to be covered
or protected with a 15-minute rated (ULC approved) thermal barrier
in buildings where there is a life safety concern or processing hazards.
This protection must stay in place during the early stages of a fire
and prevent an increase in temperature behind the barrier of over 250
degrees F. for a minimum of 15 minutes. Some local bylaws require
a rating higher than 15 minutes.
6 NAEDA EQUIPMENT DEALER October 2005
Federated’s position
Federated Insurance requires exposed polyurethane to be protected in
accordance with the current building code. The underwriter may relax
this requirement when a risk has no processing of any type that could act
as an ignition source for the polyurethane and where the property values
are less than $100,000 (fire line). This could be a building used as a cold
storage warehouse at a farm equipment dealership, for example.
Available “approved” thermal barriers
There are a variety of “approved” thermal barriers on the market and
obtaining these should not be a problem for any building owner. Most
insulating contractors who apply polyurethane insulation will also
supply and install some type of approved thermal barrier. This could
be a solid barrier, such as rated fireguard drywall, or a spray-on cement
cover, such as stucco. Whatever the barrier, it must have the ULC approval to be acceptable.
Conclusion
We have been told there have been some changes made over the
years to the mixtures of foam plastic insulation to reduce the fire
hazard. This is likely correct, however, these changes have not been
sufficient to change the existing fire code to protect this type of
insulation. If foam plastic insulation is installed by a professional
contractor and covered with an approved thermal barrier, it is an
effective and safe insulation. I
DOUG STEWART is a loss prevention trainer for Federated Insurance of Canada. For
information, call 800/665-1934 or visit Federated online at www.federated.ca.