The overall objective of the Hanford Tank Farm Occupational Exposure and Risk Assessment Plan (hereafter referred to as the “Assessment Plan”) is to provide the Tank Operations Contractor (TOC), Washington River Protection Solutions (WRPS), and the U.S. Department of Energy (DOE) with a plan for developing a transparent, peer-reviewed process for assessing potential health risks associated with worker exposures to chemical emissions from the Hanford tank farms. Revision 1 (2018) incorporates changes to the original draft plan prepared in 2016 to reflect updated strategies based on initial implementation of the recommended actions.