I am a professional HVAC technician with Dor-Mar Heating & Air Conditioning. I recently completed an estimate for a radon mitigation system for a customer. Radon is a naturally occurring radioactive gas that can be harmful to human health. It is caused by the breakdown of uranium in soil and rocks and can seep into homes through cracks in the foundation or other openings. Radon mitigation systems are designed to reduce the levels of radon in a home and prevent it from entering the breathing zone. In this particular case, I used a combination of a sub-slab depressurization system and an active sub-slab depressurization system to reduce the radon levels in the customer's home. The sub-slab depressurization system involves installing a vent pipe in the basement and connecting it to a sump pump. The sump pump will draw the radon-rich air out of the basement and exhaust it outside. The active sub-slab depressurization system involves installing a fan in the basement and connecting it to a