Building Codes : I read through the first 3 chapters of the Uniform Building Code Vol. 1 and found this passage under Chapter 2 - Defintions, Section 204 - C. Corrosive - is a chemical that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact. A chemical is considered to be corrosive if, when tested on the intact skin of albino rabbits by the method described in the United States Department of Transporation in Appendix A to 49 C.F.R. 173, it destroys or changes irreversibly the structure of the tissue at the site of contact folowing an exposure period of four hours. This term shall not refer to action on inanimate surfaces.