This paper from engineers at Cambridge University claims that a standard aroma diffuser and plastic bag is close to the performance of commercial equipment. That said, I’m not sure how much the total cost and prep time would compare to the nebulizer approach that jimrandomh suggests.
Qualitative fit testing is a popular method of ensuring the fit of sealing face masks such as N95 and FFP3 masks. Increased demand due to the coronavirus disease 2019 (COVID-19) pandemic has led to shortages in testing equipment and has forced many institutions to abandon fit testing. Three key materials are required for qualitative fit testing: the test solution, nebulizer, and testing hood. Accessible alternatives to the testing solution have been studied. This exploratory qualitative study evaluates alternatives to the nebulizer and hoods for performing qualitative fit testing.
Methods:
Four devices were trialed to replace the test kit nebulizer. Two enclosures were tested for their ability to replace the test hood. Three researchers evaluated promising replacements under multiple mask fit conditions to assess functionality and accuracy.
Results:
The aroma diffuser and smaller enclosures allowed participants to perform qualitative fit tests quickly and with high accuracy.
Conclusions:
Aroma diffusers show significant promise in their ability to allow individuals to quickly, easily, and inexpensively perform qualitative fit testing. Our findings indicate that aroma diffusers and homemade testing hoods may allow for qualitative fit testing when conventional apparatus is unavailable. Additional research is needed to evaluate the safety and reliability of these devices.
This didn’t work for me. I could taste the saccharin when wearing a surgical mask, but I couldn’t taste it (but should have) when wearing two surgical masks. I suspect that the diffuser isn’t creating the correct sizes of particles and/or is creating too many (the mask did become somewhat damp) and this may cause the smaller particles to combine into sizes that are too big or heavy to penetrate smaller gaps.
This paper from engineers at Cambridge University claims that a standard aroma diffuser and plastic bag is close to the performance of commercial equipment. That said, I’m not sure how much the total cost and prep time would compare to the nebulizer approach that jimrandomh suggests.
Paper Link
Abstract
This didn’t work for me. I could taste the saccharin when wearing a surgical mask, but I couldn’t taste it (but should have) when wearing two surgical masks. I suspect that the diffuser isn’t creating the correct sizes of particles and/or is creating too many (the mask did become somewhat damp) and this may cause the smaller particles to combine into sizes that are too big or heavy to penetrate smaller gaps.