The best choice in protecting yourself and your family against the air in an urban environment is to start by not polluting your air in the first place.
Individuals, not corporations are mainly responsible for the poor air in our cities. Choices are just that, choices. It is easy to judge people's choices in society. Smokers are often looked at in disgust, inhaling smoke knowing that it increases their chance for lung cancer and a myriad of other diseases, and yet they chose to do so anyway. People who smoke around their children are even further judged, not only choosing poor health for themselves, but subjecting their children to their choice as well. At the same time, while judging a smoker on the street, one must take into account their own contribution to the air quality that surrounds them and the health effects that their choices are subjecting the current and next generation to.
Remember, air cannot be created, it can only be recycled. Convenience outweighs almost everything else it seems for modern man. If one stops for a moment, and ponders the role they are choosing to play in the world around them, this can change. Minor choices, as minor as recycling, and buying recycled products, or products with less packaging can add up over time. There are multiple ways to reduce vehicle emissions. Cutting back on driving by using public transportation, carpooling, or walking can help. Driving a low emissions vehicle and keeping it properly maintained is an important contribution as well. Using alternate means to accomplish daily tasks, such as using the phone or Internet to shop, or telecommuting to work aid in reducing .
In your household there are basic things can be done to contribute to a cleaner environment. Insulating your home and checking your air filters monthly keep heating and cooling systems efficient. These systems should also be checked every spring and fall to ensure they are properly working. In short, it is not that difficult to take on the responsibility of caring for the world in which you live. In modern times, it is simply a matter of choosing to do so.