REI Co-op · Waterproof Sports Bags
REI Co-op Flash 18 Pack Gray
water-repellent coating likely contains PFAS; REI has not disclosed details.
The Flash 18 is a nylon daypack with water-repellent coating water-repellent treatment, typical for outdoor gear. REI provides no PFAS disclosure; traditional water-repellent coating often uses PFAS compounds.
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Material
Nylon with water-repellent coating (water-repellent) treatment
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Waterproof / stain-resistant treatment
water-repellent coating treatments have historically used PFAS.
Category baseline
clothing is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
The full breakdown
What it's made of and why it matters
The Flash 18 is constructed from nylon fabric, a synthetic polymer chosen for durability and lightweight carry. REI applies a water-repellent coating (water-repellent coating) finish to the exterior; this coating is the primary chemical concern. Nylon itself is stable and does not typically leach toxic compounds during normal use, but the finishing treatment applied to achieve water resistance is what drives the PFAS risk profile.
The brand's record and disclosure
REI Co-op has not publicly disclosed the specific water-repellent coating chemistry used on this pack or committed to PFAS-free alternatives. The brand markets sustainability and has some environmental certifications on selected products, but has remained silent on PFAS "forever chemicals" in gear. This lack of transparency is consistent across their nylon daypack line and reflects industry-wide reluctance to phase out fluorinated water repellents due to performance trade-offs.
How it compares in its category
Nylon daypacks dominate the 15-20L category, and most major outdoor brands (Osprey, Deuter, The North Face) use similar water-repellent coating treatments without disclosure. REI's Flash is mid-market in price and quality. Some newer brands now offer PFAS-free water-repellent coating alternatives (paraffin-based or silicone), but they remain less common and often reduce water-shedding performance. REI's model sits squarely in the mainstream convention of undisclosed fluorinated coatings.
If you buy it
Minimize skin contact with the exterior fabric, especially when wet or if handling a wet pack for extended periods. Do not machine wash or dry-clean; hand rinse with cool water and air dry to slow water-repellent coating degradation and reduce any potential leaching cycles. Replace the pack if the outer fabric begins to separate or show visible coating damage. Consider reapplying non-fluorinated water-repellent coating treatments (paraffin-based) after several years if water repellency declines.
Beyond PFAS: other things we checked
Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”
water-repellent coating (water-repellent coating) coating composition
REI has not disclosed whether the Flash 18 uses fluorinated or fluorine-free water-repellent coating. Industry standard for nylon daypacks at this price point is fluorinated (PFAS-based); absence of communication suggests conventional C6 or C8 fluorocarbon treatment.
Formaldehyde in dyes or finishing resins
No documented reports of formaldehyde-releaser resins or excessive formaldehyde in REI Co-op nylon textiles. Standard nylon dyeing does not require formaldehyde; no evidence of non-compliance with textile chemical standards on this model.
Azo dyes
Gray nylon is typically dyed with non-azo colorants (acid or disperse dyes for polyamide). No recalls or testing data suggest restricted azo dyes in REI packs; gray is a lower-risk color chemically.
Flame retardant coatings
Daypacks are not typically treated with flame retardants unless marketed for specific hazard environments. No evidence REI applies FR chemicals to this model.
Nylon fiber degradation and microfiber shedding
Nylon fabric sheds microfibers during washing and wear; regular laundering accelerates this. The Flash 18 is designed for outdoor use and will shed, particularly if hand-washed or worn against skin. This is inherent to nylon, not specific to REI, but relevant to cumulative microplastic exposure.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 45% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
Safer alternatives in Waterproof Sports Bags
Garmin
Carrying Case
Neoprene or polyester case, material unspecified
Unknown material raises concern; no PFAS disclosure from Garmin.
⚠Risky category by default
Patagonia
Guidewater Sling
recycled polyester with water-repellent coating finish
Lower concern; brand committed to PFAS-free water-repellent coating, but verify current batch
⚠Waterproof or stain-proof treatment
More waterproof sports bags grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.