If you buy outdoor fabric and you have been quietly assuming that domestic and imported flag fabric are essentially the same product with a different price tag, there is one chemistry fact you have been missing. Most imported outdoor fabric carries a treatment called DWR — durable water repellent — and DWR is a PFAS. This post explains what that means, why Glaser Mills does not apply it, and how to think about it as a buyer.
PFAS in plain English
PFAS stands for per- and polyfluoroalkyl substances. They are a family of roughly twelve thousand synthetic chemicals built around a carbon–fluorine bond that almost nothing in nature can break down. That is where the popular nickname comes from: forever chemicals.
Once these chemicals get into soil, water, or a person, they tend to stay. The detailed health research is still catching up to the chemistry, but the broad pattern is settled enough that public-health bodies treat the class with caution. The mechanism that worries most researchers is not exotic — PFAS alter how your endocrine system reads its own signals.
Why DWR sits at the worst end of that class
DWR is the specific PFAS-class chemistry applied to most outdoor fabric to make it bead water. It has been characterized, in industry discussion, as the worst PFAS chemical on the planet.
That phrasing is direct, but the technical case behind it is straightforward. DWR was engineered to persist on fabric for the life of the garment. The same persistence that makes DWR useful on a jacket also makes it difficult for the body to clear. The same persistence that keeps a flag dry even during a hurricane also makes the chemicals show up in the people who handle the fabric — cutting table, in storage, and downstream at the consumer level.
Epidemiological work has linked DWR to cancer clusters in affected communities. We are not going to restate that here as a clinical claim. If you want the public-health literature, your state or provincial environmental agency is the right starting point.
What this means for the flag, banner, tent, or awning buyer
If you source imported outdoor fabric, the DWR is already on the roll when it lands. You are not making a choice at the point of import — the choice was made by the mill that treated it. What you are choosing is whether your suppliers will tell you what is on it.
A few practical questions worth raising:
- What does the importer’s spec sheet say about surface treatments?
- Does the mill test incoming fabric for PFAS, and at what detection limit?
- For the people handling fabric in your shop — cutting, sewing, knitting — what is the ventilation story during routine operations?
- For indoor storage of large stock, are you comfortable with the chemistry sitting in your back room?
The Glaser Mills position
We do not apply DWR to our flag fabric. We do not use PFAS chemistry in our production process. The result is a fabric that is safer at the cutting table and in storage than the imported alternative, and one that holds its color across rolls because we dye to completion, wash and clear the fabric afterwards, and do not rely on chemistry to cover up a cheap or incomplete dye method.
Get in touch
Want to compare a Glaser Mills roll against your current source? Ask for a swatch. Want to talk through what an alternative spec would look like for an order you have already placed? Start a conversation. Our team picks up the phone.
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