Recently, people in the western portion of our country have been battling smoke throughout their cities. In some parts, the smoke is so bad that people are barely able to go outside. I hate the smell of smoke, and I definitely would not want to get a mouthful of it every time I walk outside. A friend of mine is a really bad smoker, and I really hate when he smokes around me. One question that came up for people in the area is regarding their air conditioning system. People were wondering whether it would be safe for them to continue to run their A/C systems in the house. They were afraid that the air conditioning systems would bring in air from the outside and cause serious injury from the smoke. The question came up so frequently that a major air conditioning manufacturer wrote an article advising whether it was safe or not. To summarize their article, the air conditioning manufacturer assured people that using an air conditioning system in the house was perfectly safe. They advised that the air conditioning system would cycle in clean air, and it has a filtering system that would prevent much smoke from getting in the house. While they did note that there was a potential for some smoke to get into the house, they advised that the air conditioning system would eliminate a very high percentage of it. They also advised that window A/C units are better at keeping in clean air, but they also noted that the window units are not as good at being sealed from the outside. Ultimately, most people chose to keep their A/C units running.