Services | Microbial Control & Prevention

We remediate plumbing systems contaminated by environmental source biofilm-associated pathogens, such as Legionella, Pseudomonas and Non-Tuberculous Mycobacteria (NTM). We help commission new and renovated buildings by disinfecting the potable water systems prior to beneficial occupancy. And we provide continuous supplemental disinfection of potable water systems.

We provide turnkey services: we configure, install and maintain our purpose-built equipment. We supply all required treatment chemicals. We monitor equipment functions and levels of treatment chemicals 24/7. And we document everything we do, consistent with the record-keeping requirements of ANSI/ASHRAE Standard 188-2018, Legionellosis: Risk Management for Building Water Systems and the CMS/The Joint Commission requirements for water management in healthcare facilities.

Background

Legionella and other environmental-source pathogenic (disease-causing) microorganisms are present in most public water supplies, typically in very low or even undetectable concentrations. In the absence of control, conditions in building water systems may support significant growth of these pathogens, which can then exit the system by splashing or in microscopic droplets, for example from showers, sinks, and ornamental fountains.

The microbial ecology of building water systems is primarily defined by biofilm, the slime layer found on all wet surfaces, including the inside walls of pipes and plumbing components. Plumbing biofilms are complex, dynamic microbial communities where most plumbing-associated pathogens flourish. The biofilms impair the effectiveness of most physical and chemical control methods. Legionella, Pseudomonas, Non-tuberculous mycobacteria (NTM) and other clinically important pathogens are known to invade and replicate within protozoa that are associated with biofilms. While inside these protozoa, the bacteria are protected from chemical disinfectants and temperature extremes.

Acute Treatment to Establish Microbial Control

In order to establish microbial control in a building’s potable water system, we implement treatments designed specifically to remove established biofilm and inactivate (kill) biofilm-associated pathogens, including but not limited to Legionella. Our remedial treatment protocols are designed to minimize adverse effects on plumbing materials, such as elastomers and metals. For remedial treatment, we use a combination of chemicals, including the oxidizing biocides chlorine and chlorine dioxide, each of which is approved for drinking water. However, we apply the chemicals at concentrations higher than the regulatory limits established by EPA. Therefore, we take the affected portions of the potable water system out of service during treatment. After treatment is complete, we flush the system with clean, potable water and take measurements to confirm that levels of treatment chemicals are within acceptable limits.

Continuous Supplemental Disinfection to Maintain Microbial Control

In order to maintain microbial control in a building’s potable water system, we first do the work necessary to understand the details of the plumbing—e.g., how the potable water is received, stored, heated, distributed and used. Working in close cooperation with the client’s facility management, maintenance staff and water consultants, we take physical and chemical measurements throughout the system—e.g., temperature, pH, and flow rates. This helps us identify growth supportive conditions and informs our recommendations. Based on what we learn, we design and implement a site-specific continuous supplemental disinfection protocol, most often with chlorine. We continue to monitor treatment and to consider ongoing results of physical, chemical and microbial tests made to validate the facility’s water management program, making any adjustments as necessary to optimize treatment.

Prevent Waterborne Disease

The waterborne disease burden from microbial pathogens in potable water systems in buildings is significant and increasing, both in the United States and worldwide. Attention has focused primarily on Legionella, but disease from other biofilm-associated environmental-source pathogens, such as Pseudomonas and Non-Tuberculous Mycobacteria (NTM), is also considerable. According to US Centers for Disease Control and Prevention (CDC), the implementation of water management programs consistent with the methodology in ANSI/ASHRAE 188 can prevent 9 out of 10 waterborne disease outbreaks associated with buildings. In general, disinfection is most effective when implemented as an integral part of a multi-barrier program that addresses the four key factors that support microbial growth: accumulation of sediment, tepid water temperatures, excessive water age and lack of a disinfectant residual throughout the building’s hot and cold potable water. By managing these factors in a comprehensive, integrated plan, growth-supportive conditions can be effectively controlled and plumbing-associated waterborne disease can be prevented.