The bundle provides three packages:

The mhchem package provides commands for typesetting chemical molecular formulae and equations.

The hpstatement package provides commands for the official hazard statements and precautionary statements (H and P statements) that are used to label chemicals.

The rsphrase package provides commands for the official Risk and Safety (R and S) Phrases that are used to label chemicals.

See also r-und-s.

The author is Martin Hensel. The package is Copyright © 2004-2013 Martin Hensel.