Editor’s Note: This article was originally published on June 22, 2023. It has since been updated to reflect current best practices and evolving standards.
Legionella-related disease outbreaks in the United States have been reported by the CDC as steadily increasing since 2000, peaking in 2018 with more than three cases per 100,000 people. In their 2020-2021 report, the CDC found that 15% of confirmed Legionnaires’ disease cases were, at the very least, correlated with a healthcare exposure.
While Legionnaires’ disease is typically fatal only 10% of the time, that number jumps to 25% for healthcare-associated infections. The higher risk of in-patient populations means protecting healthcare facility water systems from Legionella and other bacterial contamination is essential not only for patient safety but also to avoid survey deficiencies, operational disruption, and regulatory risk.
That’s why the Centers for Medicare & Medicaid Services (CMS) requires healthcare facilities to develop water management programs that address Legionella risk.
The Regulation
ASHRAE Standard 188 establishes the minimum risk management requirements for Legionella prevention in facility piping systems. Not only is it the industry best practice, but it’s what CMS requires.
The standard provides comprehensive requirements for facilities to design, maintain, and protect their water systems from Legionella proliferation and contamination. This includes everything from identifying hazards and ensuring system visibility to developing a complete program and implementing control measures.
Aligned with Standard 188 is ASHRAE Guideline 12, which provides detailed instructions to support compliance with the standard, while highlighting critical risks and common hazardous connections, fixtures, and conditions.
A Note on ASHRAE 514
You have heard of ASHRAE Standard 514 and wonder where it fits in. Released in 2023, Standard 514 provides more expansive requirements for facility water management programs, going beyond the scope of 188 which is primarily focused on Legionella prevention. Standard 514 includes and builds upon the best practices established by 188, expanding to other hazard areas such as other bacterial microbes, chemical contamination, and physical risks.
CMS has not adopted and applied Standard 514 as of 2026, but the practices and guidance outlined are a useful tool for developing comprehensive water management programs that protect patients, potable water systems, and your entire healthcare facility.
7 Steps to Compliance
So, what does a CMS-certified, ASHRAE 188-compliant water management program look like? The standard explicitly outlines seven key elements designed to make your steps to compliance straightforward, clear, and attainable:
- Assembling Your Team
- Mapping Your Water System
- Identifying the Risks
- Mitigating the Risks
- Monitoring & Responding
- Reviewing Progress
- Documentation
The common thread? Having ready-to-respond staff, comprehensive system knowledge, and a plan in place to identify and address risks. Many hospitals struggle not with understanding the steps but with executing them consistently, documenting them properly, and proving compliance during an audit.
