“The lack of water testing before the outbreak is not unusual. There are few regulations in the United States for monitoring building plumbing for Legionella. The rules that do exist largely target the healthcare industry.
Outside of healthcare, building owners generally are doing very little to prevent bacterial growth in their plumbing, according to interviews with people involved in Legionella testing and monitoring. Standards and industry best practices are followed haphazardly.”
AquaMedix produces and sells point of use (POU) filters to remove Legionella, the cause of Legionnaire’s Disease, from water systems in healthcare, long term care and hospitality facilities.
https://www.circleofblue.org/2019/wef/vast-differences-in-legionnaires-disease-response-by-industry/