Assessing Activities of Daily Living by Measuring Residential Water Use with Low Cost Thermistors

The ongoing assessment of well-being can enable aging adults to remain independent and continue to age in place in their own home. This provides them with a better quality of life and reduces demand on the limited supply of supportive living spaces. The assessment of changes in activities of daily living (ADL) including hygiene and food preparation such as reduced frequency or absence is important to support aging in place and independence. The measurement of when water is used, the use duration and where it is used within the home are assessments of importance within many ADLs. It can provide an indication of the ongoing capability for the resident(s) for daily hygiene (washroom) and nutrition (kitchen). This paper presents the use of low-cost thermistors applied to the outside of the hot and cold water pipes at point of use. This is an example of sensor substitution to measure water use where this substitution is important as the installation of typical flow meters can be complex especially if they are added to the pipes at multiple points of use. When water flows through the pipe, the pipe's temperature deviates from a steady-state room temperature and the paper shows how this deviation is detected by the system to indicate water use, distinguish between hot and cold water use and lastly measure the duration of water use. The sensor and presented method allow for the independent detection of hot and cold water. This provides an additional assessment that can be used in supportive smart home well-being and ADL assessment systems.