Independent Lab Testing
Filter Test Reports
Every Totobobo filter is independently tested so the numbers behind our masks can be checked, not just claimed. The reports below were produced by Nelson Labs in the United States — one of the world’s leading testing facilities for filtration media.
Each filter grade is measured for particulate, bacterial, and viral filtration efficiency, with the full PDF report linked for every test. The PRO99 filter was separately certified to N99 level in China.
How to read these reports
- MPS
- Mean Particle Size
- PFE
- Particulate Filtration Efficiency
- BFE
- Bacterial Filtration Efficiency
- VFE
- Viral Filtration Efficiency
Nelson Labs, USA Independent
Test results from Nelson Labs, USA.
F96 Filter
Highest-efficiency grade
| Test | Particle size | Conditions | Efficiency | Report |
|---|---|---|---|---|
| PFE | 0.1 μm | Latex particle challenge | 99.86% | PDF F96-PFE |
| BFE | 2.9 μm | ΔP 11.4 Pa/cm² · 8 L/min | 99.9%* | PDF F96-BFE |
| VFE | 2.9 μm | Viral challenge | 99.9%* | PDF F96-VFE |
F94 Filter
High-efficiency grade
| Test | Particle size | Conditions | Efficiency | Report |
|---|---|---|---|---|
| PFE | 0.1 μm | Latex particle challenge | 99.71% | PDF F94-PFE |
| BFE | 2.9 μm | ΔP 11.4 Pa/cm² · 8 L/min | 99.9%* | PDF F94-BFE |
| VFE | 2.9 μm | Viral challenge | 99.9%* | PDF F94-VFE |
F92 Filter
Everyday-efficiency grade
| Test | Particle size | Conditions | Efficiency | Report |
|---|---|---|---|---|
| PFE | 0.1 μm | Latex particle challenge | 99.6% | PDF F92-PFE |
PRO99 Filter N99 Rated
Certified by the National Labor Protect Utensils Quality Supervision and Inspection Center (Beijing).
PRO99 Filter
Rated N99 level
| N99 certification | National Labor Protect Utensils Quality Supervision & Inspection Center, Beijing | PDF F99 |
* Figures marked with an asterisk are reported by the laboratory as 99.9% or greater.
See all our peer-reviewed studies.