Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2021 Aug 25;18(17):8955. doi: 10.3390/ijerph18178955

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2021 by the authors.

Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

PMC Copyright notice

Number concentrations of sub-0.5-, 0.5-, 1-, and 2.5-μm particles measured in the corner of the office for (a–d) closed-door cases with (a) air purifier off, (b) low-speed air purifier turned on after particle generation, (c) high-speed air purifier turned on after particle generation, and (d) high-speed air purifier running from the beginning of particle generation; and (e,f) open-door cases with (e) air purifier off and (f) high-speed air purifier running from the beginning of particle generation.

Number concentrations of sub-0.5-, 0.5-, 1-, and 2.5-μm particles measured in the corner of the office for (a–d) closed-door cases with (a) air purifier off, (b) low-speed air purifier turned on after particle generation, (c) high-speed air purifier turned on after particle generation, and (d) high-speed air purifier running from the beginning of particle generation; and (e,f) open-door cases with (e) air purifier off and (f) high-speed air purifier running from the beginning of particle generation.