According to a USA Today report, some hotels have taken green cleaning to the next level by specifically focusing on the elimination of allergens in guest rooms. In fact, in one Doubletree Hotel, an entire floor has been dedicated to becoming "allergy-friendly" through the use of odorless disinfectants and air purifiers.

The "spaces have been cleaned and sanitized, then misted with a compound that prevents bacterial growth. Pillows and mattresses are swaddled in hypoallergenic encasements to keep out dust mites. And air purifiers keep odors, plus dust and other allergens, at bay," according to the article.

These rooms are targeted towards travelers who have garden-variety allergies, chemical sensitivities or travelers who want to guarantee a healthy environment. In fact, the demand for hypoallergenic rooms ranks right up there with high-speed internet and improved comfort beds.

Click here to read more information on these allergy-friendly environments.