The indication instrument is filled with glycerine (conform with FDA regulations) or with isolation oil in cases of the presence of limit switches to achieve a damping behavior during high vibrations as well as to avoid condensation during the use at different temperatures. Thus, it ideally meets the high requirements of hygienic design and processing. Several orientations of the thermometer are available to enable a proper readability of the instrument in different installation positions.
The skin of young children and babies is very delicate and can be easily
burnt. For this reason, it is important to make sure that your baby's
bath isn't too hot. Fill the bucket or baby bath tub and check the
temperature before starting your baby's bath. A floating thermometer can
help you judge whether your baby's bath is at the right temperature.
Some models change colour and can double-up as an extra bath toy for
your baby. If you cannot find a bath thermometer, check the water with
the inside of your wrist. It should be comfortably warm but not hot.
https://www.babycenter.in/a561363/top-7-bathroom-safety-products#ixzz511tHsGiB