SYNONYMS THPS; Pyroset TKO; Retardol S; Octakis(hydroxymethyl)diphosphonium sulfate; Tetrakis(hydroxymethyl)phosphonium sulfate (2:1); Bis(tetrakis(hydroxymethyl)phosphonium)sulfate CAS NO. 55566-30-8; 58591-11-0; 65257-04-7