Originally Posted by steve dunham
... confused with RV anti freeze (propylene glycol) which is non toxic. I worked at a vegetable oil refining plant and I believe we processed soybeans to make glycol for use in latex paints and RV anti freeze and toxicity was not a major issue
I maintain the scales at the edge of the marine mammal pools at Sea World San Diego that the Orcas and Dolphins are trained to leap out of the water and land on, thus weighing
themselves in the presence of the trainers and veterinarians much in the same way that humans do at their doctors' offices.
The pools that these animals live in are filled with 55 degree Fahrenheit salt water. The scales are electronic, yet must function in this environment. What one company has designed is an intermediate hydro-static pressure sensor system to place the electronic components remote from the cold salt water, while being connected through the digital-to-hydrostatic transfer module to the platform the animals weigh on.
The hydrostatic (or hydraulic) fluid must be:
- High viscosity to flow without loss of pressure transfer at low temperature
- non-toxic so leakage does not harm the animals
The closed-loop fluid chosen is 50% distilled water, 50% propylene glycol, and red food coloring... or in other words diluted RV anti-freeze