Surgical Mask Filtration Explained: BFE, PFE and ASTM F2100 Testing
Quick Summary: A surgical mask's job is filtration, and the numbers on the box are how you verify it does that job. This guide walks through the two test methods behind ASTM F2100 — BFE (bacterial filtration efficiency) and PFE (particulate filtration efficiency) — explains the Level 1/2/3 thresholds, and gives Canadian clinic and LTC buyers a practical checklist for reading technical data sheets. Read time: 8 minutes.
1. Why Filtration Numbers Matter to a Procurement Decision
A procurement manager at a Canadian clinic does not order masks because the packaging looks professional. They order because the mask meets a documented standard, and the standard exists because filtration is a measurable, repeatable property. ASTM F2100 is the specification most Canadian suppliers reference for medical face masks, and it is built on two laboratory tests that answer two different questions.
The first question is bacterial: if a droplet carrying bacteria lands on the mask, how much of it gets stopped? That is BFE. The second question is particulate: if aerosol particles of a defined size hit the material, what percentage is filtered? That is PFE. Neither test alone describes the whole product; together they give a buyer the two numbers that matter most when comparing masks from different vendors.
2. BFE — Bacterial Filtration Efficiency
BFE is measured using ASTM F2101, the standard test method for evaluating the bacterial filtration efficiency of medical face mask materials. The test aerosolizes a suspension of Staphylococcus aureus — a bacterium commonly associated with healthcare-acquired infections — at a controlled particle size of approximately 3.0 micrometres, and passes it through the mask material at a fixed flow rate.
The result is a percentage. A mask with BFE ≥ 98% blocks at least 98% of the bacterial aerosol under test conditions. ASTM F2100 requires:
| Mask Level (ASTM F2100) | BFE (ASTM F2101) | PFE (ASTM F2299, 0.1 µm) | Differential Pressure |
|---|---|---|---|
| Level 1 — Low barrier | ≥ 95% | ≥ 95% | < 4.0 mm H₂O/cm² |
| Level 2 — Moderate barrier | ≥ 98% | ≥ 98% | < 5.0 mm H₂O/cm² |
| Level 3 — High barrier | ≥ 98% | ≥ 98% | < 5.0 mm H₂O/cm² |
The difference between Level 1 and Levels 2–3 on BFE is small on paper but meaningful in practice. Level 2 and Level 3 both require ≥98% BFE; the levels diverge on fluid resistance, which is why a Level 3 mask is the more conservative choice for procedures with splash or spray risk. CliniEco Medical carries ASTM F2100 Level 3 face masks in 50-count boxes and Level 1 procedure masks so facilities can match the level to the procedure mix. Related: which ASTM face mask level your clinic needs.
3. PFE — Particulate Filtration Efficiency
PFE under ASTM F2100 is tested against ASTM F2299, which challenges the material with latex or polystyrene particles at 0.1 micrometres — smaller than most respiratory droplets. A 0.1 µm particle is a demanding target, and the ≥95% or ≥98% PFE thresholds under ASTM F2100 tell a buyer how the material performs against submicron aerosols.
There is a common confusion worth clearing up: PFE on a surgical mask box is not the same as N95 filtration. N95 respirators are tested under NIOSH standards (42 CFR Part 84) against sodium chloride aerosols at a 0.3 µm most-penetrating particle size, and must capture ≥95%. A surgical mask's PFE number comes from a different test method and a different test agent, so the two percentages cannot be compared directly. Surgical masks are not respirators, and a Level 3 mask with 98% PFE is not a substitute for a fit-tested N95 respirator where one is required.
4. How the Tests Are Actually Run
Both tests are performed by third-party laboratories on finished mask material or finished masks, depending on the claim. The lab conditions matter: aerosol flow rate, particle challenge concentration, and conditioning of the material before testing all influence results. A reputable supplier will share the full test report, not just the summary numbers, and the report will name the laboratory and the test method.
For a Canadian buyer, the practical habit is simple: when a data sheet says "BFE ≥ 98%", ask which standard was used. ASTM F2101 is the recognized method for BFE. If a supplier cannot name the method behind the number, treat the number as marketing, not evidence.
5. Beyond Filtration: What Else ASTM F2100 Covers
ASTM F2100 is a specification, which means it bundles several performance requirements into one standard. Besides BFE and PFE, the standard covers:
- Fluid resistance — the mask's ability to resist penetration by synthetic blood, tested under ASTM F1862 at a defined pressure (80 mm Hg for Level 1, 120 mm Hg for Level 2, 160 mm Hg for Level 3).
- Differential pressure (Delta P) — a breathability measurement; lower values mean easier breathing for the wearer.
- Flame spread — resistance to burning, relevant in surgical settings where ignition sources may be present.
That is why two masks with identical-looking "98%" numbers can perform very differently in a dental or surgical environment. Filtration is one axis; fluid resistance is the other. A Level 1 mask protects against droplets in low-risk settings, while a Level 3 mask adds splash protection for procedures where blood or body fluid exposure is likely.
6. Canadian Context: What Regulators Expect
In Canada, medical masks are medical devices. Health Canada regulates them under the Medical Devices Regulations (SOR/98-282), and Class I masks — which covers most non-sterile surgical and procedure masks — do not require a Medical Device Licence before sale; the manufacturer or importer must hold a Medical Device Establishment Licence and follow the regulatory requirements for Class I devices.
The Public Health Agency of Canada (PHAC) guidance on infection prevention and control references masks and respirators for routine practices and additional precautions. Provincial guidance, such as Ontario's infection prevention and control requirements for clinics and long-term care homes, expects facilities to have documented PPE policies. A documented standard like ASTM F2100 is the common language between the manufacturer's claim and the facility's audit trail.
7. Reading a Technical Data Sheet Like a Buyer
When comparing masks from distributors, use the data sheet as the tiebreaker. A practical checklist for Canadian clinic and LTC buyers:
| Check | What to look for | Why it matters |
|---|---|---|
| Standard cited | ASTM F2100, with the edition (e.g., F2100-19) | Confirms the mask is tested against the recognized specification |
| Test methods named | ASTM F2101 for BFE, ASTM F2299 for PFE, ASTM F1862 for fluid resistance | Numbers without methods cannot be verified |
| Level declared | Level 1, 2, or 3 | Maps directly to your procedure mix and risk profile |
| Test report available | Full lab report from a third-party lab | Evidence, not marketing language |
| Packaging claim matches | Level on the box matches the data sheet | Prevents inventory mix-ups at the receiving dock |
8. Which Level Does Your Facility Actually Need?
The level selection is a risk decision, not a price preference. A family clinic doing examinations, injections, and routine blood draws can run comfortably on Level 1 or Level 2 procedure masks for most encounters, keeping Level 3 for procedures with splash risk. A dental practice, where aerosol-generating procedures are routine, typically moves to Level 2 or Level 3 across the operatory.
LTC homes have a different pattern: most care is not aerosol-generating, but staff work close to residents with frequent coughing, so a Level 2 mask is a common baseline for outbreak precautions. The key is that the chosen level is written into the facility's PPE policy, so staff know which mask to reach for in which situation. Facilities that want a Canadian-made option can compare the Aurelia Level 2 ASTM F2100 mask made in Canada, while clinics that distribute masks to individual exam rooms often prefer individually wrapped 3-ply surgical masks.
9. FAQ
Q1: What is the difference between BFE and PFE on a surgical mask box?
BFE (bacterial filtration efficiency) measures how well the mask blocks a bacterial aerosol (Staphylococcus aureus, ~3.0 µm) using ASTM F2101. PFE (particulate filtration efficiency) measures how well it filters 0.1 µm latex or polystyrene particles using ASTM F2299. Both are reported as percentages, and both are required under ASTM F2100.
Q2: Is a mask with 98% PFE the same as an N95 respirator?
No. N95 respirators are tested under NIOSH standards (42 CFR Part 84) with a different aerosol and particle size, and they must also be fit-tested. A surgical mask is not a respirator. Use a fit-tested N95 or higher where respiratory protection is required, not a surgical mask.
Q3: What does ASTM F2100 Level 3 mean?
ASTM F2100 Level 3 is the high-barrier tier for medical face masks: ≥98% BFE, ≥98% PFE at 0.1 µm, fluid resistance to synthetic blood at 160 mm Hg, and a Delta P below 5.0 mm H₂O/cm². It is the conservative choice for procedures with splash or spray risk.
Q4: Do surgical masks need Health Canada approval?
Medical masks are medical devices in Canada. Most non-sterile Class I masks require the manufacturer or importer to hold a Medical Device Establishment Licence under SOR/98-282; they do not require a product licence. Buyers should confirm the supplier's establishment licensing and documented testing.
Q5: How often should a clinic replace its mask stock?
Disposable masks are single-use. In inventory terms, clinics typically keep a four-to-eight-week buffer and rotate stock by expiry date. Masks have a shelf life, and storing them in humid or hot conditions degrades filtration — keep them dry and at room temperature.
Q6: Can a Level 1 mask be used in a dental operatory?
For aerosol-generating dental procedures, most provincial IPAC guidance and dental regulators expect a higher barrier — typically Level 2 or Level 3. Level 1 is suited to low-risk, non-aerosol encounters. Match the level to the procedure risk, and document the policy.
Q7: What is a normal Delta P for a surgical mask?
Delta P (differential pressure) measures breathability. ASTM F2100 requires Level 1 masks to be below 4.0 mm H₂O/cm² and Level 2–3 masks below 5.0 mm H₂O/cm². Lower Delta P means easier breathing; very breathable masks tend to be more comfortable for staff wearing them all shift.
Q8: Where can Canadian facilities buy verified ASTM F2100 masks?
Buy from distributors that publish the standard, level, and test report for each product. CliniEco Medical supplies ASTM F2100 Level 1, Level 2, and Level 3 masks to Canadian clinics and LTC homes with documented specifications, in 50-count boxes and bulk case options for facility procurement.
10. Final Word for Procurement Managers
Filtration is not a marketing claim; it is a measured property with named test methods. When a mask box says BFE and PFE, check the standard behind them (ASTM F2101 and ASTM F2299), confirm the ASTM F2100 level matches your procedure mix, and ask for the lab report. Facilities that do this buy masks that perform, and they can show an auditor exactly why the product on the shelf is there.
CliniEco Medical supplies ASTM F2100 Level 1, 2, and 3 medical face masks to Canadian clinics, dental practices, and long-term care homes, with documented specifications and bulk case pricing. If your facility is reviewing mask inventory or wants a quote, contact our sales team — we support healthcare buyers across Canada with consistent supply and transparent product documentation.
Last updated: August 17, 2026. This article is for general information and does not constitute medical, legal, or regulatory advice. Follow your provincial IPAC requirements and applicable occupational health rules.
Related reading: explore our infection control resources for clinics.
decode HAI, SSI, CJD and MDRO acronyms in our infection control pillar article.
References
- ASTM International. ASTM F2100 — Standard Specification for Performance of Materials Used in Medical Face Masks. https://www.astm.org/f2100-19.html
- ASTM International. ASTM F2101 — Standard Test Method for Evaluating the Bacterial Filtration Efficiency (BFE) of Medical Face Mask Materials. https://www.astm.org/f2101-19.html
- ASTM International. ASTM F2299 — Standard Test Method for Determining the Initial Efficiency of Materials Used in Medical Face Masks to Penetration by Particulates Using Latex Spheres. https://www.astm.org/f2299-03.html
- Government of Canada. Medical Devices Regulations (SOR/98-282). https://laws-lois.justice.gc.ca/eng/regulations/SOR-98-282/
- Health Canada. Medical devices — how devices are approved and authorized in Canada. https://www.canada.ca/en/health-canada/services/drugs-health-products/medical-devices.html
- Public Health Agency of Canada. Infection prevention and control. https://www.canada.ca/en/public-health/services/infection-prevention-control.html
- World Health Organization. Advice on the use of masks in the context of COVID-19. https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public/when-and-how-to-use-masks
- Centers for Disease Control and Prevention. NIOSH N95 respirators. https://www.cdc.gov/niosh/npptl/topics/respirators/
- Antimicrobial Resistance & Infection Control (Springer, open access). https://link.springer.com/journal/13756
- Journal of Hospital Infection (Elsevier). https://www.sciencedirect.com/journal/journal-of-hospital-infection
- American Journal of Infection Control (Elsevier). https://www.sciencedirect.com/journal/american-journal-of-infection-control
- Infection Control & Hospital Epidemiology (Cambridge). https://www.cambridge.org/core/journals/infection-control-and-hospital-epidemiology
- Emerging Infectious Diseases (CDC). https://wwwnc.cdc.gov/eid/
- Canadian Centre for Occupational Health and Safety (CCOHS). https://www.ccohs.ca/
- CMAJ (Canadian Medical Association Journal). https://www.cmaj.ca/
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