Everything contained in the 2018 TLVs® and BEIs® book – all of the TLVs® for Chemical Substances and Physical Agents and all of the BEIs® (including the Notice of Intended Changes and Appendices). Introductions to each section provide the philosophical and practical bases for the uses and limitations. The Chemical Substances and Physical Agents TLVs® and the BEIs® are available in searchable PDF format.