scholarly journals Analysis of building plumbing system flushing practices and communications

2019 ◽  
Vol 17 (2) ◽  
pp. 196-203 ◽  
Author(s):  
Lisa Ragain ◽  
Sheldon Masters ◽  
Timothy A. Bartrand ◽  
Jennifer L. Clancy ◽  
Andrew J. Whelton
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Grade Level ◽  
Water Distribution ◽  
Cold Water ◽  
Expert Elicitation ◽  
Hot Water ◽  
Single Family ◽  
Point Of Entry ◽  
12Th Grade

Abstract Drinking water distribution system contamination incidents can prompt public agencies and drinking water utilities to issue do-not-drink and do-not-use advisories. After the contaminant is cleared from distribution mains, consumers are often directed to flush their plumbing. However, little validated guidance and few evaluated communications strategies are available on using flushing to decontaminate building water systems. Additionally, limited data support the effectiveness of current practices and recommendations. In this study, expert elicitation was used to assess existing flushing guidance and develop validated flushing guidance and communications for single-family residences. The resulting guidance recommends progressively opening all cold-water taps from the closest to point of entry to the furthest and allowing the water to run for at least 20 minutes. Hot-water taps should be opened progressively and run for at least 75 minutes. The guidance language and format conformed to grade-level and readability scores within recommended health communication ranges. The readability of eight other flushing guidance documents was also evaluated for contamination incidents from 2008–2015. Seven were written at a 10th–12th grade level, above the 6th–7th grade level recommended for health communications.

Determinants of Legionella pneumophila Contamination of Water Distribution Systems: 15-Hospital Prospective Study

1987 ◽  
Vol 8 (9) ◽  
pp. 357-363 ◽  
Author(s):  
Richard M. Vickers ◽  
Victor L. Yu ◽  
S. Sue Hanna ◽  
Paul Muraca ◽  
Warren Diven ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Cold Water ◽  
Physicochemical Characteristics ◽  
Hot Water ◽  
Environmental Study ◽  
Water Tank ◽  
One Year

AbstractWe conducted a prospective environmental study for Legionella pneumophila in 15 hospitals in Pennsylvania. Hot water tanks, cold water sites, faucets, and show-erheads were surveyed four times over a one-year period. Sixty percent (9/15) of hospitals surveyed were contaminated with L pneumophila. Although contamination could not be linked to a specific municipal water supplier, most of the contaminated supplies came from rivers. Parameters found to be significantly associated with contamination included elevated hot water temperature, vertical configuration of the hot water tank, older tanks, and elevated calcium and magnesium concentrations of the water (P < 0.05). This study suggests that L pneumophila contamination could be predicted based on design of the distribution system, as well as physicochemical characteristics of the water.

scholarly journals Persistence of Nontuberculous Mycobacteria in a Drinking Water System after Addition of Filtration Treatment

2006 ◽  
Vol 72 (9) ◽  
pp. 5864-5869 ◽  
Author(s):  
Elizabeth D. Hilborn ◽  
Terry C. Covert ◽  
Mitchell A. Yakrus ◽  
Stephanie I. Harris ◽  
Sandra F. Donnelly ◽  
...  
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Cold Water ◽  
Nontuberculous Mycobacteria ◽  
Treatment Plant ◽  
Water System ◽  
Drinking Water Treatment ◽  
Drinking Water System

ABSTRACT There is evidence that drinking water may be a source of infections with pathogenic nontuberculous mycobacteria (NTM) in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determine whether we could detect a reduction in the prevalence of NTM recovered from an unfiltered surface drinking water system after the addition of ozonation and filtration treatment and to characterize NTM isolates by using molecular methods. We sampled water from two initially unfiltered surface drinking water treatment plants over a 29-month period. One plant received the addition of filtration and ozonation after 6 months of sampling. Sample sites included those at treatment plant effluents, distributed water, and cold water taps (point-of-use [POU] sites) in public or commercial buildings located within each distribution system. NTM were recovered from 27% of the sites. POU sites yielded the majority of NTM, with >50% recovery despite the addition of ozonation and filtration. Closely related electrophoretic groups of Mycobacterium avium were found to persist at POU sites for up to 26 months. Water collected from POU cold water outlets was persistently colonized with NTM despite the addition of ozonation and filtration to a drinking water system. This suggests that cold water POU outlets need to be considered as a potential source of chronic human exposure to NTM.

Model of a System-Wide Domestic Hot-Water Distribution System in a Multi-Resident High-Rise Building

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Marin Vratonjic ◽  
Ali Rahmatmand ◽  
Feras Marish ◽  
Pierre Sullivan
Keyword(s):  
Distribution System ◽  
Water Distribution ◽  
Cold Water ◽  
Field Measurements ◽  
Hot Water ◽  
Domestic Hot Water ◽  
High Rise ◽  
Advanced Analysis ◽  
Component Failures ◽  
Story Building

Abstract To reduce the environmental impact and cost, energy and water consumption of multi-resident buildings should be improved while ensuring resident comfort. Inefficient mixing of hot and cold-water streams and a non-optimal domestic hot-water (DHW) distribution system design can cause higher energy consumption, component failures, and dissatisfied residents. An OpenModelica (OM) system-wide model of a 14-story building consisting of a controlled-loop injection (CLI) device and a DHW distribution system is presented. The OM results are validated against field measurements at discreet locations within a single-zone closed-loop circuit to ensure the validity of time-varying temperature and flowrate. The study demonstrates that OM is a useful engineering tool to model single and multi-zone high-rise buildings that allows advanced analysis, including system-wide optimization, advanced on-demand controls, and energy and water-usage efficiencies.

Isolation of Legionella pneumophila from the Cold Water of Hospital Ice Machines: Implications for Origin and Transmission of the Organism

1985 ◽  
Vol 6 (4) ◽  
pp. 141-146 ◽  
Author(s):  
Janet E. Stout ◽  
Victor L. Yu ◽  
Paul Muraca
Keyword(s):  
Legionella Pneumophila ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Cold Water ◽  
Water System ◽  
Primary Source ◽  
Hot Water ◽  
Hospital Environment ◽  
Water Storage Tank

AbstractAlthough the mode of transmission of L. pneumophila is as yet unclear, the hot water distribution system has been shown to be the reservoir for Legionella within the hospital environment. In this report we identify a previously unrecognized reservoir for L. pneumophila within the hospital environment, ie, the cold water dispensers of hospital ice machines. The cold water dispensers of 14 ice machines were cultured monthly over a 1-year period. Positive cultures were obtained from 8 of 14 dispensers, yielding from 1 to 300 CFU/plate. We were able to link the positivity of these cold water sites to the incoming cold water supply by recovering L. pneumophila from the cold water storage tank, which is directly supplied by the incoming municipal water line. This was accomplished by a novel enrichment experiment designed to duplicate the conditions (temperature, sediment, stagnation, and continuous seeding) of the hot water system. Our data indicate that significant contamination of cold water outlets with L. pneumophila can occur. Although no epidemiologic link to disease was made, the fact that the primary source of a patient's drinking water is from the ice machines warrants further investigation of these water sources as possible reservoirs.

scholarly journals Saving cold drinking water in residential hot water distribution systems

2020 ◽  
Vol 24 ◽  
pp. e4
Author(s):  
Marcelo Dalmédico Ioris ◽  
Enedir Ghisi
Keyword(s):  
Drinking Water ◽  
Distribution Systems ◽  
Water Distribution ◽  
Cold Water ◽  
Solenoid Valve ◽  
Hot Water ◽  
Water Tank ◽  
Vertical Pipe ◽  
Plumbing Systems ◽  
Approximate Amount

In homes that have instantaneous gas heaters to heat water, cold water is wasted in the first seconds of using hot water fixtures. This waste is caused due to the large lengths of piping between the hot water fixtures and the heater that feeds them. The water in such pipes suffers thermal losses over time. When turning on the fixtures, this drinking water, because it is cold, is rejected by users, especially when using showers. This work deals with the conformation of a system that avoids wasting water in residential hot water services. To establish this conformation, a usual plumbing design was analysed to verify the changes proposed in order to optimise the operation of the system. The gas-heated hot water pipes are currently installed so that the pipes start at the heater and run through the entire house to the hot water fixtures furthest from the heater. It was found that the waste of water in a water fixture decreases if there is the consumption of hot water previously in one of the water fixtures of the house. To avoid this waste, according to the configuration of the current plumbing systems, it is necessary to install an additional set of electronic equipment that automatically redirects the cold water − that would be wasted − to a water tank for later use. The system proposed is composed of a solenoid valve located at the end of the hot water pipe. This valve has the function of letting flow to the water tank the approximate amount of cold water that would be wasted. Through a radio frequency signal sent when a button located near the hot water fixtures is pressed, the system recognises which water fixture was turned on and the approximate amount of cold water that must be released through the valve until the arrival of hot water from the heater. Then, there must be a pipe that collects the water that flows through the solenoid valve. Such pipe will be connected to a vertical pipe, responsible for collecting water from all flats and directing the water to the water tank. The installation of the system is based on the recommendations of the standards used in Brazil and the most frequent configuration found in homes. This work also serves as a guide for installing the system in homes other than the example shown herein.

Assessment of Lisbon drinking water distribution network biofilm colonization and associated hazards

2008 ◽  
Vol 8 (4) ◽  
pp. 421-426
Author(s):  
J. Menaia ◽  
M. Benoliel ◽  
A. Lopes ◽  
C. Neto ◽  
E. Ferreira ◽  
...  
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Water Distribution Network ◽  
Storage Tanks ◽  
Water Pipe ◽  
Cultural Methods ◽  
Drinking Water Distribution ◽  
And Storage

Concerns arise from the possible occurrence of pathogens in drinking water pipe biofilms and storage tank sediments. In these studies, biofilm samples from pipes and sediments from storage tanks of the Lisbon drinking water distribution system were analyzed. Protein determinations and heterotrophic counts on pipe biofilm samples were used to assess the Lisbon network sessile colonization intensity and distribution. Indicator and pathogenic microorganisms were analyzed in pipe biofilm samples, as well as in storage tanks biofilm and sediments, by using cultural methods and PCR, to assess risks. Results have shown that the Lisbon network sessile colonization is relatively weak in intensity. In addition, no meaningful hazards were apparent for both the network biofilm and the storage tanks biofilm and sediments.

Persistence and decontamination of surrogate radioisotopes in a model drinking water distribution system

2009 ◽  
Vol 43 (20) ◽  
pp. 5005-5014 ◽  
Author(s):  
Jeffrey G. Szabo ◽  
Christopher A. Impellitteri ◽  
Shekar Govindaswamy ◽  
John S. Hall
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Drinking Water Distribution System ◽  
Drinking Water Distribution

VULNERABILITY ASSESSMENT OF A DRINKING WATER DISTRIBUTION SYSTEM

2007 ◽  
Vol 2007 (1) ◽  
pp. 449-467
Author(s):  
Stacia L. Thompson ◽  
Elizabeth Casman ◽  
Paul Fischbeck ◽  
Mitchell J. Small ◽  
Jeanne M. VanBriesen
Keyword(s):  
Drinking Water ◽  
Vulnerability Assessment ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Drinking Water Distribution System ◽  
Drinking Water Distribution
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