Water-blocking Asphyxia of N95 Medical Respirator During Hot Environment Work Tasks With Whole-body Enclosed Anti-bioaerosol Suit

Jintuo Zhu; Qijun Jiang; Yuxuan Ye; Xinjian He; Jiang Shao; Xinyu Li; Xijie Zhao; Huan Xu; Qi Hu

Safety and Health at Work (Dec 2023)

Water-blocking Asphyxia of N95 Medical Respirator During Hot Environment Work Tasks With Whole-body Enclosed Anti-bioaerosol Suit

Jintuo Zhu,
Qijun Jiang,
Yuxuan Ye,
Xinjian He,
Jiang Shao,
Xinyu Li,
Xijie Zhao,
Huan Xu,
Qi Hu

Affiliations

Jintuo Zhu: Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Ministry of Education, Xuzhou, Jiangsu, China; National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology, School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China
Qijun Jiang: Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Ministry of Education, Xuzhou, Jiangsu, China; National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology, School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China
Yuxuan Ye: Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Ministry of Education, Xuzhou, Jiangsu, China; National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology, School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China
Xinjian He: Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Ministry of Education, Xuzhou, Jiangsu, China; National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology, School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; Corresponding author. School of Safety Engineering, China University of Mining and Technology, 221116, Xuzhou, Jiangsu, China.
Jiang Shao: School of Architecture & Design, China University of Mining and Technology, Xuzhou, Jiangsu, China
Xinyu Li: Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Ministry of Education, Xuzhou, Jiangsu, China; National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology, School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China
Xijie Zhao: School of Architecture & Design, China University of Mining and Technology, Xuzhou, Jiangsu, China
Huan Xu: School of Materials Science and Physics, China University of Mining and Technology, Xuzhou, Jiangsu, China
Qi Hu: Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining and Technology), Ministry of Education, Xuzhou, Jiangsu, China; National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology, School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China

Journal volume & issue: Vol. 14, no. 4
pp. 457 – 466

Abstract

Read online

Background: During hot environment work tasks with whole-body enclosed anti-bioaerosol suit, the combined effect of heavy sweating and exhaled hot humid air may cause the N95 medical respirator to saturate with water/sweat (i.e., water-blocking). Methods: 32 young male subjects with different body mass indexes (BMI) in whole-body protection (N95 medical respirator + one-piece protective suit + head covering + protective face screen + gloves + shoe covers) were asked to simulate waste collecting from each isolated room in a seven-story building at 27-28°C, and the weight, inhalation resistance (Rf), and aerosol penetration of the respirator before worn and after water-blocking were analyzed. Results: All subjects reported water-blocking asphyxia of the N95 respirators within 36-67 min of the task. When water-blocking occurred, the Rf and 10-200 nm total aerosol penetration (Pt) of the respirators reached up to 1270-1810 Pa and 17.3-23.3%, respectively, which were 10 and 8 times of that before wearing. The most penetration particle size of the respirators increased from 49-65 nm before worn to 115-154 nm under water-blocking condition, and the corresponding maximum size-dependent aerosol penetration increased from 2.5-3.5% to 20-27%. With the increase of BMI, the water-blocking occurrence time firstly increased then reduced, while the Rf, Pt, and absorbed water all increased significantly. Conclusions: This study reveals respirator water-blocking and its serious negative impacts on respiratory protection. When performing moderate-to-high-load tasks with whole-body protection in a hot environment, it is recommended that respirator be replaced with a new one at least every hour to avoid water-blocking asphyxia.

Published in Safety and Health at Work

ISSN: 2093-7911 (Print); 2093-7997 (Online)
Publisher: Elsevier
Country of publisher: Netherlands
LCC subjects: Medicine: Public aspects of medicine
Website: http://www.journals.elsevier.com/safety-and-health-at-work/

About the journal

Abstract

Keywords