What are Conventional, Hybrid, and OAT Additives?

Nick Dobrez

Nick Dobrez | February 4, 2018


Conventional, hybrid, and OAT additives have distinct properties that makes each one unique:

Conventional coolant additives are sometimes referred to as Inorganic Additive Technology (IAT). This includes corrosion inhibition with traditional chemistries. Such chemicals may include nitrite, nitrate, silicate, borate, phosphate, molybdate, and azoles.

Hybrid coolant additives use an organic acid as the primary corrosion inhibitor and also heavily depend on various inorganic supplements such as silicate, nitrate, phosphate, and molybdate. Heavy-duty versions may contain nitrite. Three substantial subcategories exist: American hybrids may not use benzoate, a common organic acid in European coolants, but a different organic acid and otherwise look similar to conventional fully-formulated approaches. European styles rarely use phosphate; Asian styles rarely use silicate and may use multiple carboxylates in combination.

OAT coolant additives stands for Organic Acid Technology. These additives rely primarily on carboxylic acids and azoles. They generally do not contain silicate or borate. Heavy-duty versions may also contain nitrite or molybdate, or both, but they still fall in the OAT family.