33Understanding the particle size distribution in the air and patterns of environmental 34 contamination of SARS-CoV-2 is essential for infection prevention policies. We aimed to 35 detect SARS-CoV-2 surface and air contamination and study associated patient-level factors. 36 245 surface samples were collected from 30 airborne infection isolation rooms of COVID-19 37 patients, and air sampling was conducted in 3 rooms. 38Air sampling detected SARS-CoV-2 PCR-positive particles of sizes >4 µm and 1-4 µm in 39 two rooms, which warrants further study of the airborne transmission potential of SARS-40 CoV-2. 56.7% of rooms had at least one environmental surface contaminated. High touch 41 surface contamination was shown in ten (66.7%) out of 15 patients in the first week of illness, 42 and three (20%) beyond the first week of illness (p = 0.010). 43All rights reserved. No reuse allowed without permission.