1.1 ,This test method covers the use of a portable refractometer for determining the approximate freezing protection provided by ethylene and propylene glycol-based coolant solutions as used in engine cooling systems and special applications.
Note 1: ,Some instruments have a supplementary freezing protection scale for methoxypropanol coolants. Others carry a supplemental scale calibrated in density or specific gravity readings of sulfuric acid solutions so that the refractometer can be used to determine the charged condition of lead acid storage batteries.