Describes the requirements for chemical composition for the following families of soft solder alloys: - tin-lead, with and without antimony, bismuth, cadmium, copper, and silver; - tin-antimony; - tin-bismuth; - tin-copper, with and without silver; - tin-indium, with and without silver and bismuth; - tin-silver, with and without copper and bismuth; - tin-zinc, with and without bismuth.