We evaluated the effectiveness of respiratory protection, to reduce children’s personal exposure to particulate air pollution (PAP). Children and their carers were also asked about the usability of the inventions to establish their acceptability, both in the short term and as a longer, more sustainable solution. This project was made up of two elements:

1) Fit of KN95-style respirators (marketed for children). We tested facemask fit, on children, given the proliferation of facemasks to protect them from exposure to outdoor PAP and the great uncertainty as to whether children’s masks can be effective at reducing their exposure. The fit was measured using a TSI Portacount. The test included a series of standardized activities performed while wearing the respirator for ~3 min. Each mask was tested with and without a clip/strap to tighten the earloops around the head. The child’s face shape and size were alsoe determined using standardized methods. Efficacy was measured by the fit factor (PM2.5 concentrations outside divided by
inside the mask).

2) Filtration of respirators (marketed for children). We conducted filtration efficiency experiments on selected respirators to test whether they met the requirements of N95 standards. 

Results

An infographic for children gives the results of the fit tests for Nepal and Indonesia: http://face-up-consortium.webspace.durham.ac.uk/wp-content/uploads/2026/08/WP2-infographic-FINAL_English.pptx

The published findings of this project are available at:

Fit tests: www.sciencedirect.com/science/article/pii/S1438463925000434

Filtration tests: https://www.isrp.com/~documents/the-isrp-journal/journal-public-abstracts/do-child-size-respirators-sold-in-indonesia-and-nepal-meet-standard-adult-performance-requirements-for-filtration-and-air-resistance-and-requirements-as-modified-for-children-vol-42-no-1-202