Conclusion

The standard mask with the lowest requirements on filtration effectiveness is the single use face masks (not to be confused with surgical masks). Surgical masks have higher requirements, and respirators have the highest requirements. Respirators also usually fit tighter around they face (data shows they score higher on fit effectiveness) than surgical masks and single-use face masks.

DIY Masks should focus on being sealed around the face, as filtration specifications are completely dependent on there being no leak around the mask. The seal to the face is the most critical element in protecting the lungs aside from filters. Additionally, a single size of mask cannot not effectively seal to the faces of all users, masks should come in multiple sizes to fit children to large adults.