Question from ptomcik
Hello Debra,
Do you think that if I encased sofa cushions with the same material used to encase mattresses to make them dust mite proof it would prevent the flame retardants from escaping? One website has a cotton material with a pore size of 4.91 microns and a polyester covering with a pore size of 2.8 microns. I’m not sure I understand if it is the actual flame retardent chemical that is liberated from foam and then combines with dust or if it combines with dust in the foam and then is liberated.
Thank you,
PT, Pittsburgh
Debra’s Answer
This is a pretty technical question.
First, there are many different flame retardants used. You would need to find out which flame retardant is on your sofa.
And then you would need to know the particle size of that specific flame retardant (here’s a chart of particle/micron sizes of various common materials: Particle Sizing Chart.
Different flame retardants have different particle sizes. Two I was able to find quickly are Antimony Pentoxide (0.03 microns) and Antimony Trioxide (0.25-3.0 Micron). In searching for these, I found that flame retardants are formulated and sold in various particle sizes–the same flame retardant can be purchased in different particle sizes, so even if you knew the flame retardant, you probably couldn’t find out the particle size.
So let’s say that your sofa has Antimony Trioxide (0.25-3.0 Micron). Your cotton material with a pore size of 4.91 microns and a polyester covering with a pore size of 2.8 microns. That means that there is a “hole” that is 4.91 microns in size, or 2.8 microns. So anything smaller than that pore size would go through, like a 10-inch basketball could go through a 24-inch hoop.
A molecule of 0.25-3.0 Micron could go through the cotton pore of 4.91 no problem, so that wouldn’t be a barrier.
