Preventing Layoffs During a Public Health Emergency Act of 2020 This bill provides 100% of temporary federal financing of limited short-time compensation (STC) payments in certain states where a public health emergency has been declared. (STC, also known as work sharing, is a program within the federal-state unemployment system that provides pro-rated unemployment compensation to workers whose hours have been reduced in lieu of a layoff.) The term public health emergency means a public health emergency declared for an area by (1) the Secretary of Health and Human Services, or (2) a state public health official with the authority to declare such an emergency for the area. Certain states without a STC program may enter into an agreement with the Department of Labor under which Labor will temporarily finance 50% of the state's STC payments. If such a state subsequently enacts a state law implementing a STC program that meets federal requirements it shall be ineligible for such 50% financing; however, it shall be eligible for the 100% financing. Labor must develop and provide model legislative language for states to develop and enact STC programs, including periodically reviewing and revising such language; provide technical assistance and guidance in developing, enacting, and implementing STC programs; and establish certain STC reporting requirements.