The four main equipment communication standards are the SECS-I (which stands for SEMI Equipment Communication Standards) established in 1978 that deals with communication protocol and physical definitions, the SECS-II established in 1982 that deals with message format, the GEM established in 1992 that refines the SECS-II, and the HSMS that supersedes SECS-I established in 1994. The organization also provides safety and ergonomics guidelines, the first of which was the SEMI S2 developed in 1993, followed by the SEMI S8 in 1995.