I have used Safety King for about 20 years and though they are not the lowest in cost for air duct cleaning, they are the BEST. I have allergies and asthma and Safety King has always done a top notch job. When I downsized to a smaller house 11 years ago, they were able to solve the cigarette smell in the duct work left by previous owners with one of their productst. Every 4-5 yrs they clean the ducts and they spray a hospital safe mold remediation product to further clean the air. I know I will have a clean indoors for the winter months ahead. The specialists that come out are knowledgable and are not in a hurry. They do a thorough job, taking adequate time, and then taking pictures of before and after of your ducts. There are other companies out there but I have never tried them because when you can breathe clean air, are happy, are safe, and have had excellent service, why look? Bravo to Safety King! Not paid or asked to say this at all… I just stand by them after several satisfied years of using their service. Katherine is wonderful on the phone, answering any questions with a smile. And this time around, Eric and Josh were polite, on time, and did a fabulous job!