Catalog · Physics of COVID-19 Transmission Lecture 37 of 49 Video 4-11: Safety Guideline for COVID-19—Reopening Schools or Businesses ← Previous Video 4-10: Safety Guideline for COVID-19—Risk Scenarios Next → Video 4-12: Safety Guideline for COVID-19—Vaccination and Immunity ✓ Mark complete Materials Transcript (PDF) ↗ transcript