Nanograms per millilitre per hour (ng/mL/hr)

Some medical tests report results in nanograms per millilitre per hour.

A nanogram is one-billionth of a gram. A gram is about 1/30 of an ounce.
A millilitre measures fluid volume equal to 1/1000 litre. A litre is a little bigger than a quart.
An hour is the time period that the amount of nanograms per millilitre is measured for.