🌫️ PM10 / PM2.5 particulate matter concentration in air
Gravimetric determination of PM10 and PM2.5 suspended particulate matter mass concentration in ambient air. Reference method for EU air quality monitoring.
Overview
Suspended particulate matter PM10 (particles with aerodynamic diameter ≤10 µm) and PM2.5 (≤2.5 µm) are among the most important air pollutants, directly affecting human health. PM2.5 penetrates into alveoli and bloodstream, causing respiratory diseases, cardiovascular diseases and lung cancer. Poland is among EU countries with the worst air quality — PM10 and PM2.5 exceedances affect dozens of zones during the heating season.
The gravimetric method described in PN-EN 12341 is the reference method required by Directive 2008/50/EC (CAFE) and Polish regulations on air quality assessment. It consists of collecting dust on a filter through a PM10 or PM2.5 separation head at constant air flow, followed by weighing the filter before and after exposure under controlled climatic conditions.
In Poland, gravimetric measurements are conducted by GIOŚ at approximately 180 PM10 stations and 70 PM2.5 stations. Sequential samplers automatically exchange filters every 24 hours, and weighing analysis is performed in accredited laboratories. The method is supplemented by automatic continuous analyzers (TEOM, beta-attenuation), which however require calibration against the reference method.
Standard PN-EN 12341:2023 defines requirements for reference samplers, including nominal flow rate 2.3 m³/h for low-flow systems and 30 m³/h for high-flow systems, sampling time 24 h, filter types and conditioning conditions.
Method principle
Ambient air is drawn through a separation head (impactor or cyclone) cutting off the fraction above PM10 or PM2.5 with specified cut-off curve accuracy (D50). Particles smaller than the threshold deposit on a quartz fiber or PTFE filter. The filter is conditioned before and after exposure in a room with controlled temperature (20±1°C) and humidity (50±5% RH) for min. 48 h, then weighed on an analytical microbalance (resolution 1 µg). The difference in filter mass after and before exposure, related to the volume of sampled air (at standard conditions), gives the mass concentration of dust in µg/m³.
Applications
- Ambient air quality monitoring (GIOŚ, WIOŚ)
- Compliance assessment with EU standards — PM10 (50 µg/m³ / 24h), PM2.5 (25 µg/m³ / year)
- Protection zones and air protection programs (POP)
- Environmental impact assessment (EIA) of investments
- Scientific research — dust chemical composition, emission sources
- Immission measurements in the vicinity of industrial plants
- Verification of automatic continuous analyzers (TEOM, beta)
Key parameters
| Parameter | Value |
|---|---|
| Measurement range | 1–1 000 µg/m³ |
| Weighing resolution | 1 µg (microbalance) |
| Nominal flow (LVS) | 2.3 m³/h ± 2% |
| Sampling time | 24 h ± 1 h |
| Conditioning conditions | 20±1°C, 50±5% RH, min. 48 h |
| Limit of quantification | ~1.5 µg/m³ (for 55.2 m³ air) |
Standard
- Standard number
- PN-EN 12341:2023
- Title (PL)
- Powietrze atmosferyczne — Standardowa grawimetryczna metoda pomiarowa do oznaczania stężenia masowego frakcji PM10 lub PM2,5 pyłu zawieszonego
- Title (EN)
- Ambient air — Standard gravimetric measurement method for the determination of the PM10 or PM2.5 mass concentration of suspended particulate matter
Step-by-step procedure
1. Conditioning of clean filters
Place clean quartz filters in climatic chamber (20±1°C, 50±5% RH) for min. 48 h. Handle filter with antistatic tweezers.
2. Weighing of clean filters
Weigh each filter on microbalance (resolution 1 µg) at least 2 times. Difference ≤10 µg. Record mass m₁.
3. Filter transport and loading
Transfer filters in transport cassettes to measurement station. Load into sequential sampler (14 filters for 2 weeks).
4. Sample collection (24h)
Sampler automatically feeds air through PM10/PM2.5 head at flow 2.3 m³/h for 24h. Daily filter exchange.
5. Collection of exposed filters
After 14 days collect cassettes with filters. Transport under conditions minimizing contamination and material loss.
6. Conditioning of exposed filters
Place exposed filters in climatic chamber (20±1°C, 50±5% RH) for min. 48 h.
7. Weighing of exposed filters
Weigh each filter at least 2 times. Difference ≤10 µg. Record mass m₂.
8. Quality control — blank filter
Per weighing series weigh field blank filter. Correct result for blank value.
9. Concentration calculation
C = (m₂ − m₁) / V, where V = flow × time [m³, standard conditions 293 K, 101.3 kPa]. Result in µg/m³.
10. Reporting
Report contains: daily PM10/PM2.5 concentration, air volume, meteorological conditions, measurement uncertainty. Data to JPOAT/GIOŚ database.
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| Reference sampler LVS (low-flow) | Leckel SEQ 47/50, Sven Leckel GmbH | 60 000–120 000 PLN |
| Reference sampler HVS (high-flow) | Digitel DHA-80, Andersen RAAS10 | 80 000–160 000 PLN |
| PM10/PM2.5 separation head | Leckel PM10/PM2.5 inlet, Sharp-cut cyclone | 5 000–15 000 PLN |
| Analytical microbalance | Mettler Toledo XPR2U (0.1 µg), Sartorius Cubis II | 40 000–120 000 PLN |
| Climatic chamber for filter conditioning | Weiss Technik, Memmert HPP260 | 30 000–80 000 PLN |
| Quartz fiber filters ∅47 mm | Whatman QM-A, Pall Tissuquartz | 8–15 PLN/pc. |
Reagents, media and consumables
| Reagent | CAS | Details |
|---|---|---|
| Quartz filters (Quartz Fiber) | — | Whatman QM-A or Pall Tissuquartz 2500QAT, ∅47 mm, heated at 500°C/3h, for gravimetric analysis |
| PTFE filters (Teflon) | — | Pall Zefluor, ∅47 mm, for chemical analysis (metals, ions), low hygroscopicity |
| Silica gel | 112926-00-8 | To maintain humidity in conditioning chamber |
| Mass standards (balance calibration) | — | OIML E2, set 1 mg – 200 g, certified GUM/PTB |
Health and safety (OHS)
- Exposed filters may contain heavy metals and PAHs — nitrile gloves mandatory
- Work at height when operating measurement stations — harnesses and OSH training
- Microbalance — antivibration workstation, no drafts, electrostatic control (ionizer)
- Climatic chamber — risk of electric shock, periodic inspections