" â¤½Inside the home, make sure your filters and carpets are clean. Doctors recommend Saline irrigation and a humidifier. Up to 50% humidity inside the house can help ease symptoms caused by pollution.â¤Fortunately for people suffering from constant allergies, the best furnace filters can alleviate their anxieties and symptoms. Indoor pollution can be prevented by Merv air filters found at Online Allergy Relief. Allergy causing agents from the immediate environment may be hard to avoid, but turning the home into an allergy-safe place is possible with the right practices and smart choices."