MOLD ARMOR Mold Blocker is waterproof and prevents mold growth for up to 3 months. This mold blocker creates an invisible barrier to prevent mold growth on indoor and outdoor surfaces. This anti-mold spray is for use in bathrooms, linens, draperies, fabrics, apparel, carpets, bedding, upholstery, and furniture. To use, spray surface until wet. Allow to air dry. Repeat every 3 months on fabric surfaces and every 7 days on hard, non-porous surfaces. Follow all directions carefully.