Legislation in the Netherlands requires routine analysis of drinking water samples for cultivable Legionella species from high-priority installations. A field study was conducted to investigate the presence of Legionella species in thermostatic shower mixer taps. Water samples and the interior of ten thermostatic shower mixer taps were investigated for cultivable Legionella species. In seven cases, Legionella species was found in at least one of the samples. In four cases, Legionella species was detected in the biofilm on the thermostatic shower mixer taps interior, with the highest values on rubber parts, and in five cases in the cold supply water. These results show that thermostatic shower mixer taps can play a role in exceeding the threshold limit for cultivable Legionella species, but the cold supply water can also be responsible. Practical implications: This study showed that contamination of thermostatic shower mixer taps (TSMTs) with Legionella spp. was frequently observed in combination with contamination of the water system. Consequently, a combined focus is necessary to prevent the proliferation of cultivable Legionella spp. in TSMTs. In addition, the results also demonstrated that biofilms on rubbers inside the TSMT had high numbers of Legionella spp., probably because rubber contains relatively high concentrations of biodegradable substrates. Therefore, improvement of the rubber materials is necessary to reduce the proliferation of cultivable Legionella spp. in TSMTs.
DOCUMENT
Prioritaire instellingen dienen in het bezit te zijn van een beheersplan legionellapreventie. Desondanks worden in de praktijk geregeld te hoge aantallen legionellabacteriën aangetroffen in monsters genomen uit thermostatische douchemengkranen. Het is niet bekend of de thermostatische douchemengkraan zelf de oorzaak is van deze overschrijdingen. Daarom is onderzoek uitgevoerd aan douchemengkranen die afkomstig zijn uit de praktijk. De resultaten laten zien dat de douchemengkraan een rol kan spelen bij een overschrijding, maar dat ook andere onderdelen van de leidingwaterinstallatie de oorzaak kunnen zijn.
DOCUMENT
Ageing-in-place is the preferred way of living for older individuals in an ageing society. It can be facilitated through architectural and technological solutions in the home environment. Dementia poses additional challenges when designing, constructing, or retrofitting housing facilities that support ageing-in-place. Older adults with dementia and their partners ask for living environments that support independence, compensate for declining and vitality, and lower the burden of family care. This study reports the design process of a demonstration home for people with dementia through performing a literature review and focus group sessions. This design incorporates modifications in terms of architecture, interior design, the indoor environment, and technological solutions. Current design guidelines are frequently based on small-scale studies, and, therefore, more systematic field research should be performed to provide further evidence for the efficacy of solutions. The dwellings of people with dementia are used to investigate the many aspects of supportive living environments for older adults with dementia and as educational and training settings for professionals from the fields of nursing, construction, and building services engineering.
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Water quality is under pressure worldwide and requires urgent attention according to recent reports, calling for technological development and more cost-effective solutions. One such development is the use of nanobubbels (NBs). NBs have been gaining interest in both scientific and industrial fields over the past years due to their broad applicability and unique characteristics opposed to larger bubbles used in traditional applications, e.g. dissolved air flotation and aeration. NBs is promising in water technology applications, especially in aeration, as due to their small size they provide a large air-water interface and are stable (present in the bulk) for many days. Due to that, different companies have been introducing NBs based technology in the market. The start-up company BIMCO Holland is one of them. They have developed three types of Ultra Fine Bubble (UFB)-generators to integrate in various (household) applications: I) a tap connection for water taps, II) a pipe adaptor for household appliances and III) a shower coupling. In order to prove their concept, BIMCO Holland wants to test the UFB-generators together with NHL Stenden. During these tests, the intended formation of NBs in tap water will be determined, as well as possible effects on the water quality. Additionally, potential applications will be (theoretically) explored, such as reduced water- and surfactant usage and prolonged lifetime of materials and appliances. With NanoBGen, the consortium aims to understand better the functioning of the newly developed UFB-generators. The tests are required to prove the system is (or not) related to the presence of NBs. Also, to support the company finding other applications of the UFB-generators and contribute to bringing the technology to a higher TRL.