Standard colors were determined from standard solutions. However, coexisting ions can modify

reaction color. The list below reports ion concentrations under which ones interferences are

insignificant:

≤ 1000 mg/L  : B3+, Ba2+, Ca2+, Cd2+, Cl-, F-, I-, K+, Mg2+, Mn2+, Na+, NH4+, NO3-, PO43-, Sn2+, SO42-

≤ 250 mg/L    : CN-, Cr3+, Ni2+, Pb2+, Zn2+

≤ 100 mg/L    : Co2+, Mo6+

≤ 50 mg/L      : Cu2+

≤ 25 mg/L      : Al3+

≤ 10 mg/L      : Fe2+

≤ 3 mg/L        : Fe3+

sub-ppm level:  Cr6+, V5+, Residual chlorine

The Nitrite PACK TEST is suitable for sea water samlpes.