A Janitor/Custodian are a major key to preventing Major Diseases and Micro organisms such Covid 19 Flu viruses HIV and more.but the only reason to hire a certified professional is because of the amount of training hours and classes our custodians have to go through we are certified in areas such as Hospitals and Jails ect. We take the time to make sure our staff knows how to properly dispose of trash and how to  properly wear PPE and use green products and how not to  Cross Contaminate belive it or not I have seen people do this because one they are either lazy or have not been properly Trained.