Healthy Water is Essential for a Healthy Building
We have conducted recent tests that confirm that buildings subjected to shutdowns or reduced utilization due to the pandemic have shown a deterioration in their water quality when returning to pre-pandemic schedules This decline in quality has been traced to stagnant water within the buildings. CLICK HERE for water quality mag article
Numerous buildings have shown dangerously high bacterial contamination levels (>1,000,000 cfu/mL of slime molds andiron-related bacteria) within the premise piping.
In anticipation of re-opening the economy, the US EPA and the CDC issued the following guidelines for all properties affected by the shutdown: “Building and business closures for weeks or months reduce water usage, potentially leading to stagnant water inside building plumbing. This water can become unsafe to drink or otherwise use for domestic or commercial purposes. For example, optimal growth conditions for undesirable pathogens, such as Legionella bacteria, can occur when hot water temperatures decrease and disinfectant residuals (eg chlorine) drop to low levels.”
Water chemistry changes may also increase corrosion and leaching of metals, including lead, and may cause the formation of disinfection by-products. Turning on the water for immediate use after it has been stagnant can pose a risk to public health if not properly managed.Additionally, turning on water after a prolonged period of non-use could disrupt pipe and plumbing scales to such an extent that microbial and chemical contaminants could be released into the water.
In 2021, the CDC issued its Legionella Tool kit that is “designed to help people understand which buildings and devices need aLegionella water management program to reduce the risk for Legionnaires’ disease, the key elements of a water management program, and how to develop it.” This Toolkit can be found online atwww.cdc.gov/legionella/wmp/control-toolkit/index
A key component to the CDC Toolkit is the reference to the ASHRAE 12-2020 guideline, which is designed to help in reducing the risk of dangerous levels of bacterial growth in buildings:
“4.2.2.2 Growth. Biofilms play an important role in Legionella growth. Biofilms are complex and dynamic microbial ecosystems that form on surfaces within the building water systems. Biofilms impair the effectiveness of physical and chemical control methods, such as maintaining hot-water temperatures and applying chemical disinfectants.Legionella bacteria are known to invade and replicate within protozoa that are associated with biofilms. While inside these protozoa, the Legionella bacteria are further shielded from disinfectants and temperature extremes. Key factors that contribute to Legionella growth include sediment, temperature, water age, and disinfectant residual.”
The majority of problems associated with OPPPs(and with the biofilms that allow their propagation and survival), can be addressed with a water management plan that uses the detection of residual chlorine to ensure the health and safety of premise plumbing.
