This reference standards are intended to use in the determination of trace elements in fresh water. The solution contains nitric acid at a volume fraction of approximately 2%, equivalent to an amount of substance concentration (molarity) of approximately 0,32 mol/l and also it simulates the elemental composition of fresh water.

One unit consists of approximately 250 ml of acidified water in a polyethylene bottle, which is sealed in an aluminised plastic bag to maintain stability.