This FC provides guidelines for evaluating, planning, programming, and designing PMEL Facilities. Alteration and renovation projects should update existing facilities to meet the guidance and criteria within budgetary constraints. This FC is not intended as a substitution for thorough review by individual Program Managers and Operations Staff in the appropriate agency. This FC is a guide for site selection and design of a new metrology laboratory or for modification of an existing facility. This FC outlines standards for design and construction of Type II and Type III PMELs.