**5. Conclusions**

In conclusion, sensor-activated faucets with TMVs are generally more contaminated than clinical valves without thermostatic mixers. This allows us to conclude that the technologies typically chosen by a hospital do not correspond with the water microbiological environment that can develop in the SHWOs. The microbial interaction with the selected technologies, pipeline and faucet materials, and chemical-physical water characteristics result in an environment that, in semi-critical and critical areas, can lead to serious risks for patients, hospital sta ff, and stakeholders involved in maintenance procedures. The limit of this study is the lack of data on cold water after the replacement program developed by three hospitals due to there being no cold-water monitoring in the risk assessment plan, to poor knowledge, and to cost-containment demands.

The authors wish to encourage infection control teams to evaluate the use of non-touch fittings in hospitals, especially when installed in high-risk areas, and wish to promote water microbial monitoring in both hot- and cold-water distribution systems according to a water safety plan that can guide the hospital's choices based on epidemiological data, technological knowledge, and applied maintenance procedures.

**Author Contributions:** S.C. and M.M. conceived and designed the experiments and wrote the paper. L.G., M.R.P., and J.L. performed sample collection and the experiments. S.S. and A.D. performed the statistical analyses. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was partially supported by a research gran<sup>t</sup> (RFO 2018) from the University of Bologna, Italy.

**Acknowledgments:** The authors would like to thank the GVM Engineering sta ff for technical assistance and Graziella Ciani for microbiological analyses.

**Conflicts of Interest:** The authors declare no conflict of interest.
