Whether you've tried to keep your coffee hot, ordered delicious takeout from a restaurant or packed up delicate valuables before a big move, you've probably encountered Styrofoam. Produced by Dow Chemical Co., Styrofoam is actually a member of the plastic family. Despite its ubiquity, Styrofoam is a controversial material because of the risks it presents to both the environment and to people. It's non-biodegradable, and it's highly flammable.

Convenient but unhealthy polystyrene lunch boxes with take away
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Is Styrofoam a Fire Hazard?

Styrofoam and Fire Safety

It seems counterintuitive that a highly flammable substance like Styrofoam can go in the microwave. But while it can withstand some heat, it can also easily catch fire when exposed to an open flame. In addition, burning polystyrene releases styrene gas that, when inhaled, can be severely detrimental to the nervous system. Burning Styrofoam produces a sooty kind of smoke, indicating that some of the chemicals in the compounds aren't breaking down fully and are likely releasing toxic chemicals into the air.

It can, of course, be difficult to know what constitutes a fire hazard, given that fires are unpredictable. Having Styrofoam in the home in a place where it could meet with an open flame is very risky. You should keep all Styrofoam out of the kitchen and away from appliances like the grill, oven or stovetop. Also take care to keep Styrofoam away from hot water heaters, incinerators, furnaces, fireplaces and any electrical wiring that could potentially ignite.

One of Styrofoam's most popular uses is as a construction material. As evidenced by its ubiquity in the world of food and drink containers, it insulates exceptionally well. However, the high flammability of the product gives many people pause, as using it in a home or office could have disastrous consequences in the case of fire.

There's no official word on whether or not it's more flammable than wood or siding, both of which are part of many buildings, but the concern persists. The majority of plastics manufacturers claim that as an insulation product or building material, polystyrene or Styrofoam isn't an especially dangerous fire hazard, as long as you install it properly. Correct installation is subject to state and city regulations, but in general, you should protect polystyrene with a thermal barrier if you're using it as a building material for a residence or anywhere else human beings will be. There's a chance of Styrofoam igniting when exposed to an open flame, so it requires a flame barrier.

Styrofoam and Flame Retardants

There are also many concerns about the flame retardant applied to polystyrene. The EU banned this retardant due to potentially toxic chemicals that are hazardous both to living things and to the environment. However, this doesn't mean that Styrofoam is more or less likely to burn than any other building material, only that you should take extra precautions when using it in the home and around any flames.