Calcium Formate is a calcium salt of formic acid. It carries a E number (E238) as it can be used as a preservative for Animal Feed.

In the construction industry, Calcium Formate is often used as a modifier for grout and cement. It can shorten the setting time and increase hardness. Better to resistance to corrision of metal substrates in cement and grout are also a result of calcium formate addition. 

In drywall (Gypsum Board) applications, Calcium Formate can act as a flame redartant.