Paycheck Protection Program Extension Act This bill extends the Paycheck Protection Program, established to support small businesses in response to COVID-19 (i.e., coronavirus disease 2019) and expands the allowable uses for paycheck protection loans. Specifically, the bill extends the deadline to apply for a paycheck protection loan to December 31, 2020, and it allows recipients up to 16 weeks to use any funds received. Within the extended 16-week period, a recipient may elect an 8-week safe harbor in which to maintain payroll and outside of which the amount of loan forgiveness shall not be reduced because of a reduction in workforce or salary and wages. The bill also expands loan forgiveness under the program to include amounts expended on worker protection, such as physical barriers or particulate filtering respirators that are needed to comply with requirements related to sanitation, social distancing, or worker or customer safety.