Work

The influence of N95 and surgical masks on carbon dioxide levels: A comprehensive systematic review and meta-analysis

Year: 2024

Type: review

Study designs: Systematic Review, Meta-Analysis

Abstract: Objectives This study aimed to assess the impact of wearing N95 and surgical masks on carbon dioxide (CO 2 ) concentrations during various activity levels, to understand the implications for mask use in different settings, especially in light of the COVID-19 pandemic. Study design Systematic Review and Meta-Analysis. Methods A systematic review was conducted, retrieving 6798 articles from PubMed, Web of Science, and Scopus databases. Twenty-nine articles met the inclusion criteria. Mask types were categorized into N95 and surgical masks, while activities were classified as low, medium, and high. Results The meta-analysis revealed CO 2 concentrations (mmHg) for different scenarios: No mask (37.91, 95 % CI: 36.46, 39.35), N95-low (36.83, 95 % CI: 33.57, 40.10), N95-moderate (37.85, 95 % CI: 36.51, 39.20), N95-high (39.51, 95 % CI: 38.00, 41.02), N95 with exhalation valve (35.82, 95 % CI: 32.89, 38.75), N95 without exhalation valve (38.45, 95 % CI: 37.10, 39.81), surgical mask-low (38.31, 95 % CI: 34.48, 42.14), surgical mask-moderate (35.05, 95 % CI: 31.12, 38.97), surgical mask-high (36.07, 95 % CI: 34.18, 37.96). Conclusions Our findings indicate that N95 masks lead to higher CO 2 accumulation during various activities compared to surgical masks. Moreover, surgical masks exhibit higher CO 2 concentrations during low activity compared to moderate and high activities. Notably, CO 2 concentrations are higher in N95 masks without an exhalation valve compared to those with a valve. No significant difference was observed between not wearing a mask and wearing either N95 or surgical masks in terms of CO 2 accumulation. These results provide important insights for mask selection and usage recommendations in different scenarios.

Source: Heliyon

DOI: 10.1016/j.heliyon.2024.e36626