The six NFPA documents that make up this guide can be used to identify the hazardous properties of most of the chemicals in commercial use today, as well as many that are available only in laboratory sample quantities. The three chemical matrixes are new to this edition. Matrix one lists the major chemical entries and references the appropriate NFPA data document. Matrix 2 lists common synonyms and references official chemical names and the appropriate NFPA data document. Matrix 3 is a numerically ordered list of Chemical Abstracts Service (CAS) numbers and references the chemical name and the appropriate NFPA data document.