When shopping, be a skeptical consumer. The burden of proof is on the manufacturer.

• Look for Natural Fire Barriers: The safest and most transparent mattresses use materials that are naturally flame-resistant. Wool (often GOTS-certified organic) is the gold standard and is used by most high-end and organic brands. Other safe alternatives include hydrated silica, plant-based thistle pulp, and inherent FR rayon (a cellulose-based fiber).

• Ask Companies Directly: Before you buy, contact customer service via email or live chat. Get the answer in writing to this specific question: "Does this mattress, including the inner fire barrier sock, contain any fiberglass, glass fiber, or silica?" Be wary of vague answers like "our mattresses meet all federal safety standards." Demand clarity.

• Be Cautious with Old Models & Third-Party Sellers: Some brands have recently removed fiberglass from their current models. Be careful when buying older, new-in-box mattresses from third-party sites like Amazon, as they could still contain fiberglass. For example, some older Nectar and Casper models reportedly used fiberglass, while their newer lineups do not.