With all due respect, those recommendations are for Enclosed Shower Heads that do not get opened every day or, ever. Also, it was proven in ineffective in 1981 and documented by The Annals of Internal Medicine with a substance not only more aggressive but potentially deadly. Unfortunately, the virus repopulated in the Enclosed Shower Head. Given the University of Colorado Study and the fact that Immune-compromised patients can and do get infected unknowingly from a Shower Head and, potentially those that take the time to come here for help, support and potential answers, I feel it is important after the loss of my own mother to NTM related and other illness, to enlighten those that understand none of us have the corner on all the great ideas. There are those of us who will all look at the same problem and see another way to fix it. Have you ever cut open a standard popular Shower Head to see the complicated internal detail where mycobacterium which are 1 micron in size can hide? I have cut open hundreds. Here is the Study from 1981. Legionella pneumophila serogroup 6 was isolated from nine of 16 shower heads in a Chicago hospital ward where three patients had contracted Legionnaires' disease caused by serogroup 6 L. pneumophila. Each patient had showered there 2 to 10 days before the onset of disease symptoms. We also isolated the bacteria in two other hospitals, and found the same serogroups as had been causing Legionnaires' disease in those hospitals: serogroup 1 in Pittsburgh and serogroups 1 and 4 in Los Angeles. However, showers from hospital wards where no patients had contracted Legionnaires' disease also yielded L. pneumophila. Shower heads at the Chicago hospital were sterilized with ethylene oxide but rapidly became recontaminated, suggesting that the potable water at these hospitals may have contained the organism. The question of whether aerosols of shower water or other exposures to potable water containing L. pneumophila may cause nosocomial Legionnaires' disease has not been resolved but deserves further study.