Each year, millions of people suffer from seasonal allergy symptoms caused by outdoor allergens like pollen and mold spores. However, many also suffer from year-round allergies, which are triggered by indoor allergens, including dust mites, animal dander, cockroaches, and mold. Although exposure to allergens outside your home is very hard to control, it's much easier to control the allergens inside your home. If you suffer from allergies, it's a good idea to make your home as allergen-free as possible. Air conditioning can be a big help. It allows you to close all doors and windows to keep outside pollen from entering the house. Also, air conditioning lowers indoor humidity, which helps control mold and dust mites. It's very important to vacuum floors and furniture frequently to reduce dust and pollen. Use a vacuum with a high-efficiency particulate filter or a double bag for best results. Also, remove carpeting and curtains, which can attract dust and pollen. Another good idea is to keep all surfaces in the home smooth and uncluttered so they won't collect dust. When you come in from being outdoors, be sure to change your clothes and take a shower, because allergens can stick to your clothes and hair. Animal dander is another common allergen, so keep pets outside as much as possible or make sure they stay out of the bedroom. Your bedroom is probably the most important room to keep allergen-free. Dust mites can live in your mattresses and sheets, causing symptoms like sneezing and itchy eyes. To reduce these symptoms, wash bedding at least once a week and use special allergy covers on pillowcases and mattresses.