The study “Testing the Efficacy of Homemade Masks: Would They Protect in an Influenza Pandemic?” by Davies A, Thompson KA, Giri K et al. Med Public Health Prep 2013; 7: 413–418 (published: https://www.cambridge.org/core/journals/disaster-medicine-and-public-health-preparedness/article/testing-the-efficacy-of-homemade-masks-would-they-protect-in-an-influenza-pandemic/0921A05A69A9419C862FA2F35F819D55#article) has been significantly consulted by the occupational health and safety stakeholders in Germany in the course of the Corona pandemic.
One point derived from this study for the wearing of protective masks is the measured pressure drop.
In Table 1 of the study, however, I cannot find a unit for the indicated pressure drop in the right columm.
- What is the relevant measured variable for the indicated pressure drop?
- Is this the measured pressure (mbar / pa) or is it a percentage to the comparison value?
The last year published FAQ (attached) did not help me either.
Since the DIN standard for the surgical masks tested (EN14683, class 1) requires a maximum pressure difference of 40 Pa, which is 0.4 mbar, a pressure drop of 5.23 mbar would not be clear.
I tried to contact the authors of the study but did not receive any answer yet.
Any help is appreciated, thank you very much!
- Badges
- Science topic