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New State Regulations to Include Legionella Water Management Programs

What about Legionella regulations is changing?

A growing number of state and local officials in the United States are updating building and public health codes to include Legionella water management programs, an encouraging sign for those concerned with water safety and Legionella control. 

Many of the new and proposed changes to these regulations come in response to advice from the Centers for Disease Control and Prevention (CDC) to “consider changing building and public health codes to include Legionella water management programs.” 

As of April 2022, Legionella-related regulations have been established in four different states with five additional states currently considering similar legislation. In an effort to prevent Legionnaires’ disease and maintain consistency from state to state, all regulations are being based on the same standard: ASHRAE 188.

For a list of current and proposed legislation regarding Legionella regulations, please scroll down. If you have any questions about Legionella water management programs or need assistance with program design, consultation, testing, or best practices, please reach out to HPE’s Microbiology experts for assistance. HPE Director of Microbiology Jonathon Hall can be reached at jhall@hpenviron.com or by calling our offices during business hours at 703-471-4200. 


Legionella grows best in building water systems that are not well maintained. Building owners and managers should adopt newly published standards that promote Legionella water management programs, which are ways to reduce the risk of this germ in building water systems.”

-Centers for Disease Control and Prevention (CDC)

Which states have existing regulations for Legionella control?

IllinoisIllinois Public Act 102-0004 (Article 90) was adopted into law and became effective on April 27, 2021. The law requires hospitals and nursing care facilities to develop a policy for Legionella testing. The policy and test results must also be made available to the state health department when requested.

MichiganMichigan Administrative Code R 325.45303 became effective on Feb 21, 2020. The new code requires health facilities to establish and implement water management program based on the ASHRAE 188 standard. Among its requirements, the Code states that the management program must include a risk assessment, control measures and ongoing verification. Additionally, facilities with secondary or supplemental domestic water treatments must also register and comply with the Michigan Safe Water Drinking Act.

New York – According to New York State regulations, water maintenance programs are required, as well as plans for all cooling towers and Legionella testing. Hospitals and live-in or residential health care facilities must also implement a Legionella “Sampling and Management Plan” in addition to a potable (domestic) water system plan.

Both New York City Local Law 77 and Chapter 8 of the Rules of the City of New York requires testing in cooling towers and instructs all owners of cooling tower to enact a Maintenance Program and Plan (MPP) “that describes operational and administrative strategies and process control measures to be taken to prevent and control the growth of Legionella.”

VirginiaVirginia SB-410 went into effect on July 2, 2021, and requires schools to implement a water management program. Please see HPE’s updates on Virginia Bill SB-410 for more information.

Which states have proposed new Legionella regulations?

CaliforniaCalifornia Senate Bill 1144, also known as the Safe and Efficient Water Act, would require the following for properties owned or leased by a public school or state agency:

  • A water quality and efficiency assessment. This includes testing for lead, Legionella and radon in potable water systems, water features, and cooling towers;
  • Legionella management plan in buildings with cooling tower systems. The plan must include routine sampling for Legionella and bacteria and follow ASHRAE Standard 188;
  • Remediation of contaminant levels that exceed safety standards issued by the state;
  • Public notification of contamination if levels exceed state safety standards. A notice stating that contaminants have been found in building water systems must be posted in a lobby window near the primary entrance and clearly visible to the public. The notice must remain in place until the contamination is fully remediated;
  • Notification to the local health department or state officials within 24 hours of receiving a Legionella test result greater than 1,000 CFU/mL;
  • A graywater reuse feasibility study;
  • ASSE 12060 and 12080 certification for at least one person on the water management program team and the applicable ASSE 12000 certification for each person providing water testing, remediation and other water management plan services.

Agencies in California will have until January 1, 2024, to meet these requirements. Agencies that operate more than one building will have to complete at minimum 25% of the buildings before 2024 and an additional 25% each subsequent year. All buildings must be completed by January 1, 2027.

MarylandMaryland Senate Bill 302, also known as the Legionnaires’ Disease Prevention Act (Jan 20, 2022) and the corresponding bill in the House (HB-248) would require owners and/or operators of public buildings to implement a water management programs for Legionella that includes validation testing and is consistent with ASHRAE Standard 188. The bill is effective Oct 1, 2022.

New Jersey – As of March 10, 2022, New Jersey Senate Bill 1006 has replaced Bill 695. If adopted, Bill 1006 would require all public water systems in New Jersey to maintain a free chlorine level of at least 0.3 ppm (mg/L) throughout the entire system at all times. Customers must also be provided with written notice of any disruptions that could result in increased levels of Legionella bacteria. Additionally, building operators would be required to establish and enact Legionella water management programs in line with ASHRAE Standard 188.

North CarolinaNorth Carolina House Bill DRH30401-MGa-137A, also known as the “Legionnaires’ Disease Prevention Act,” would require building owners and/or operators to implement both validation testing and a Legionella water management plan per ASHRAE Standard 188, by October 1, 2022. Public water system owners and operators would also be required to carry out routine sampling and testing for Legionella as part of the new regulation.

PennsylvaniaPennsylvania Senate Bill 1125 was introduced on March 9, 2022, and would require building operators to implement water management programs in line with ASHRAE Standard 188.

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