Containers that enable blind people to determine the level of contained hot water.

To determine the water level in a container, people who are blind use electronic aids or the sound and weight of poured water. In this work, three non-powered containers were designed to assist blind people in detecting the level of hot water in a container. Their effectiveness was evaluated and compared with that of an unaugmented control container. The capacities of the designed containers and the control container were 800 mℓ. The results reveal that, when blind participants poured 400 mℓ of water into the containers, they could determine the volume of water in two of the designed containers with smaller average errors (13.03 mℓ and 26.88 mℓ) than in the control container (36.60 mℓ). One of the designs also attracted positive scores for all satisfaction-related variables and was improved in response to feedback on its prototypes.