Legionnaires’ Disease and Your Household Water

How To Decrease Risks of Legionella Exposure

According to the New Jersey Department of Health, individuals, particularly those at high risk, can follow the recommended steps below to decrease the risk of Legionella exposure and best practices to limit the growth of Legionella in household water systems and devices:

• Avoid high-risk activities. If you are at an increased risk for Legionnaires’ disease, consider avoiding hot tubs, decorative fountains, power washing, or similar activities, which may generate increased amounts of aerosols or mist. A conversation with your health care provider may help you assess your individual level of risk based on underlying health conditions and co-morbidities. Your health care provider may recommend that you consider installing specialty biological 0.2-micron filters on your showerhead if you are severely immunocompromised and receive water from Trenton Water Works.

• Maintain in-home medical equipment. If using medical equipment that requires water for use or cleaning such as non-steam generating humidifiers, CPAP or BiPAP machines, nasal irrigation devices such as Neti Pots, and attachments for nebulizers, follow manufacturer’s instructions for use and maintenance. This often includes using sterile water instead of tap water in the device.

• Clean and/or replace your showerheads and faucet aerators (screens) per manufacturer’s instructions whenever buildup is visible. This is particularly important if you haven’t cleaned your showerheads or faucet aerators recently. Cleaning might require you to remove the showerhead and hose and soak in a solution (such as white vinegar or a bleach solution) to remove buildup. If using chemicals, follow instructions found on the back of the bottle for safe use.

• Keep your water heater set to a minimum of 120^o F. This temperature will reduce Legionella growth and avoid potential for scalding (hot water burns). Setting the heater to a higher temperature may better control Legionella growth, especially if you have household members at increased risk for Legionnaires’ disease. However, if the temperature is set to greater than 120^o F, make sure you take extra precautions to mix cold and hot water at the faucet and shower to avoid scalding. If you have household members at increased risk of scalding, such as young children or older adults, you may consider installing a thermostatic mixing valve. A mixing valve allows your water to be stored at a higher temperature within your water heater to help kill bacteria while eliminating concerns with water being too hot at sinks or showers. If you decide to install a mixing valve, be sure to follow manufacturer’s instructions for routine cleaning and maintenance to avoid bacteria growth within the valve. Consider consulting with a licensed plumbing professional and ensure you are following your local codes and ordinances for home plumbing repairs.
   
  After cleaning showerheads and faucet aerators and increasing the temperature of the water heater, thoroughly flush the water at each tap (e.g., sink, showerhead) for 20 minutes. Try to minimize exposure to splashing and mist generation, for example, by leaving the room while the water is running.

• Conduct routine flushing. Sinks and shower taps that are not used often can increase the risk of Legionella growth in other areas of the home. Let your faucets and showers run for at least three minutes when they have been out of use for more than a week. Minimize exposure to splashing and mist generation, for example, by leaving the room while the water is running. Additionally, you may consider flushing your water following any water disruption to your home, such as low pressure or discoloration, resulting from a water main break or nearby hydrant flushing.

• Follow manufacturer’s instructions for maintaining your water heater and expansion tank, including periodic flushing, draining, and removal of sediment. If manufacturer’s instructions are unavailable, seek advice from a licensed professional.

• Clean and/or replace all water filters per manufacturer’s instructions. All whole-house (e.g., water softeners) and point-of-use filters (e.g., built-in refrigerator filters) must be properly maintained.

• Drain garden hoses and winterize hose bibs. Detach and drain the hose, shut the water valve off inside the home, and drain the pipe when not in use for the season.

• Follow manufacturer’s instructions for maintaining your hot tub. Ensure disinfectant levels (e.g., chlorine) and maintenance activities (e.g., cleaning, scrubbing, replacing the filter and water) are followed. For more information, be sure to review CDC’s recommendations for residential hot tub owners.

• Operate and maintain your indoor and outdoor decorative fountains according to manufacturer’s instructions to limit your exposure to Legionella. Household members at increased risk for Legionnaires’ disease should avoid exposure to decorative fountains. If manufacturer’s instructions for cleaning and maintenance are not available, minimum cleaning frequency recommendations can be found in CDC’s Legionella Control Toolkit.

• Remove, shorten, or regularly flush existing dead legs. Plumbing renovations can lead to the creation of dead legs, a section of capped pipe that contains water but has no flow (or is infrequently used). For future renovations, ensure your plumber avoids creating dead legs.

Recommended Actions for Building Owners and Property Managers

• Complete this quick yes/no worksheet to determine if your building, or certain devices in your building, need a Water Management Program. Resources to help you develop a Water Management Program and for Legionella control in common sources of exposure are available at NJDOH’s Legionella website.

• Store hot water at temperatures above 140°F and ensure hot water in circulation does not fall below 120°F (or at highest temperature allowable by local regulations and codes). Install thermostatic mixing valves as close as possible to fixtures to prevent scalding while permitting circulating hot water temperatures above 120 degrees.

• Clean and maintain water system components. This includes devices such as thermostatic mixing valves, aerators, showerheads, hoses, filters, water heaters, storage tanks, and expansion tanks, regularly per manufacturer instructions.

• Flush hot and cold water at all points of use (faucets, showers, drinking fountains) at least weekly to replace the water that has been standing in the pipes. Healthcare settings and facilities that house vulnerable populations should flush at least twice a week.
• Remove dead legs or, where unavoidable, make them as short as possible. Where a dead leg (a section of pipe capped off with little or no water flow) cannot be avoided, it should be flushed regularly to avoid water stagnation. This may require the installation of a drain valve.

• Monitor water quality parameters such as temperature, disinfectant residuals, and pH regularly. Adjust the frequency of monitoring based on stability of values. For example, increase frequency of monitoring if there is a high degree of measurement variability. Pay particular attention to water quality parameters following a water disruption event, such as low pressure or discoloration, resulting from a water main break or nearby hydrant flushing.

• Safely operate and conduct regular maintenance of cooling towers to protect staff, visitors, and the adjacent community from exposure to Legionella. Use a Water Management Program to establish, track, and improve operation and maintenance activities.

• Follow recommendations from the New Jersey Department of Health when reopening your facility following a prolonged shutdown or reduced operation due to the COVID-19 Pandemic. Recommendations are available at: https://bit.ly/3CG2s8S