I recently used to monitor the air quality in my home. The test took about one hour and and it was free. This was great service and we all need this type service in our homes, even in relatively new homes, and especially those suffering from Asthma or allergies. The Home Advisor, Doyle performed the test and Doyle was extremely knowledgeable in the field of Air Quality Cleanliness and other types of home protection in this field such as dust mites, mold, dander etc. Doyle has the proper personality for this type of business. I have has some experience after having owned several companies over the years. my test results were as follows: Low CO Levels, but high CO2 levels in a building that is less than ten years old. It looks like I have my work cut out in order to reach maximum air quality. I thoroughly recommend that homeowners have their home air quality tests performed by . after all, what is there to lose?