Catalog · Physics of COVID-19 Transmission Lecture 28 of 49 Video 4-2: Safety Guideline for COVID-19—Transmission Rate ← Previous Video 4-1: Safety Guideline for COVID-19—Cumulative Exposure Time Next → Video 4-3: Safety Guideline for COVID-19—Transient Transmission Rate ✓ Mark complete Materials Transcript (PDF) ↗ transcript