Table 2.

NIOSH and BioSpot Aerosol Samples Collected From Double-Occupancy Airborne-Infection Isolation Rooms of COVID-19 Patients

Room	No. of Patients	Day of Illness	Clinical Ct Valuesa	SARS-CoV-2 RNA Copies per m–3 Air	Aerosol Particle Size	Sampler
1	2	3; 4	23; 32.5	ND ND	<1 μm, 1–4 μm, >4 μm, <4.34 µm	NIOSHb BioSpotc
2	2	5; 4	19.6; 15	40.48 908.02	<1 μm 1-4 μm	NIOSHb
				1,083.1 469.9	>4 μm <4.34 µm	BioSpotc

Note. ND, none detected; PCR, polymerase chain reaction; Ct, cycle threshold; NIOSH, National Institute for Occupational Safety and Health.

^a PCR cycle threshold values from patient respiratory samples collected within 72 h of room sampling.

^b Six 840-L samples pooled and analyzed together (5,040 L air total). Size fractionation retained.

^c One 3,840-L sample.