This unique sealer is designed to prevent the outgassing of harmful chemicals used in carpet backing. These chemicals include such known carcinogens as formaldehyde, toluene, benzene, xylene and styrene. It effectively blocks outgassing for up to five cleanings or one year. Use in conjunction with SafeChoice® Carpet Shampoo and SafeChoice® Carpet Lock Out to clean out and seal in the harmful chemicals found in a typical carpet. Not recommended for wool.