Promoting Access to Critical Countermeasures by Ensuring Specimen Samples to Diagnostics Act or the Promoting ACCESS to Diagnostics Act This bill directs the Department of Health and Human Services (HHS) to support the development of medical products and diagnostic tests for emerging infectious diseases. Specifically, HHS must develop policies and procedures governing access by public and private entities to samples of pathogens (or suitable surrogates). The samples may be used for preparedness and response activities, developing medical products for emerging infectious diseases, and similar purposes. Additionally, HHS may contract with public and private entities to increase the capacity to rapidly develop, validate, and disseminate diagnostic tests to health departments and other entities to respond to emerging infectious diseases with significant potential to cause a public health emergency.