⛽ CFPP — Cold Filter Plugging Point
In short
Determination of the lowest temperature at which diesel fuel flows through a standardized 45 µm wire mesh filter. The test is performed according to PN-EN 116:2015; Wire mesh filter: 45 µm (355 meshes), stainless steel. The procedure comprises 9 steps (about 43 min–1 h 23 min in total); it is used for: Diesel fuel quality certificate — summer/transitional/winter/arctic grade (PN-EN 590), Quality control of FAME and B7/B10/B20 blends (PN-EN 14214), Depressant (CFPP-lowering additive) effectiveness assessment.
At a glance
- Standard: PN-EN 116:2015
- Category: Petrochemistry
- Procedure steps: 9
- Total time of stages: 43 min–1 h 23 min
- Wire mesh filter: 45 µm (355 meshes), stainless steel
- Aspiration vacuum: 1.96 kPa (200 mm H₂O)
- Sample volume: 45 mL
Overview
Cold Filter Plugging Point (CFPP) is one of the most important low-temperature parameters of diesel fuel, determining its suitability for use in winter conditions. CFPP defines the lowest temperature to which fuel can be cooled while maintaining its ability to flow through engine fuel filter — below this temperature, paraffin (wax) crystals block filter screens and prevent engine operation.
In Poland, seasonal CFPP requirements apply according to PN-EN 590: summer grade (15.04–30.09) — max 0°C, transitional grade (1.03–15.04 and 1.10–15.11) — max −10°C, winter grade (16.11–28/29.02) — max −20°C, arctic grade — max −32°C or −44°C. Fuels with FAME (biodiesel) addition show worse low-temperature properties, requiring use of depressants (CFPP-lowering additives).
The method according to EN 116 involves stepwise cooling of fuel sample and cyclic aspiration of fuel through a standardized 45 µm wire mesh filter under 1.96 kPa vacuum. Testing is performed at 1°C intervals — CFPP is the lowest temperature at which 20 mL of fuel flows through the filter in less than 60 seconds. Modern automatic apparatus perform the entire test without operator intervention.
CFPP determination is mandatory in every diesel fuel quality certificate and is a critical parameter in the autumn-winter period when refineries switch to winter grade production.
Method principle
A diesel fuel sample (45 mL) is cooled stepwise in a thermostatic cooling bath. At 1°C intervals, the sample is aspirated under 1.96 kPa (200 mm H₂O) vacuum through a standardized 45 µm wire mesh filter (355 meshes). The flow time of 20 mL of fuel through the filter is measured. Testing continues until flow time exceeds 60 seconds or fuel does not flow at all (paraffin crystals block filter). CFPP result is the last temperature at which sample passed the test positively (time ≤60 s).
Applications
- Diesel fuel quality certificate — summer/transitional/winter/arctic grade (PN-EN 590)
- Quality control of FAME and B7/B10/B20 blends (PN-EN 14214)
- Depressant (CFPP-lowering additive) effectiveness assessment
- Seasonal control at fuel depots and fuel stations
- Testing of domestic heating oils (PN-EN 14078)
- R&D research — optimization of winter fuel formulations
- Customs control and commercial inspection of fuel quality
- Determination of low-temperature properties of paraffinic fuels (GTL, HVO)
Key parameters
| Parameter | Value |
|---|---|
| Wire mesh filter | 45 µm (355 meshes), stainless steel |
| Aspiration vacuum | 1.96 kPa (200 mm H₂O) |
| Sample volume | 45 mL |
| Blockage criterion | Flow time of 20 mL >60 s or no flow |
| Temperature step | 1°C |
| PN-EN 590 limit (winter PL) | max −20°C |
Standard
- Standard number
- PN-EN 116:2015
- Title (PL)
- Oleje napędowe i domowe oleje opałowe — Oznaczanie temperatury zablokowania zimnego filtra — Metoda schładzania stopniowego
- Title (EN)
- Diesel and domestic heating fuels — Determination of cold filter plugging point — Stepwise cooling bath method
Step-by-step procedure
-
Sample preparation
Measure 45 mL of diesel fuel sample into apparatus measuring vessel. Ensure sample is at room temperature and homogeneous.
-
Filter check
Install clean 45 µm wire mesh filter in measuring head. Check vacuum system tightness.
-
Placement in apparatus
Insert vessel with sample into automatic apparatus cooling chamber. Mount measuring head with filter and temperature sensor.
-
Automatic test start
Start measurement program. Apparatus will begin cooling sample at controlled rate.
-
Cooling and cyclic measurement
At 1°C intervals, apparatus automatically aspirates sample through filter under 1.96 kPa vacuum and measures flow time of 20 mL. Positive result = time ≤60 s.
-
Blockage detection
When flow time exceeds 60 s or sample does not flow — apparatus records temperature of last positive test as CFPP.
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Result reading
Read CFPP result from apparatus display. Result is reported to 1°C accuracy.
-
Apparatus cleaning
Remove vessel and filter. Rinse filter with toluene (dissolve paraffins), then acetone. Dry with compressed air.
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Quality control
Perform duplicate and check repeatability (±2°C). Every series — measure CRM. Compare CFPP result with seasonal PN-EN 590 requirement.
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| Automatic CFPP apparatus | PAC ISL OptiFPP, Normalab CPP Classic, Koehler K45950 | 60 000–120 000 PLN |
| Cooling cabinet (4 chambers) | Normalab CPP 5Gs (chambers: 0, −18, −33, −51°C), ISL | 80 000–150 000 PLN |
| 45 µm wire mesh filters | Stainless steel filters, replaceable, EN 116 compliant | 500–1 500 PLN / 10 pcs. |
| Measuring vessels and pipettes | Graduated cylinders 50 mL, glass pipettes | 100–300 PLN |
| Reference thermometer | Certified Pt100 thermometer, 0.1°C resolution | 1 000–3 000 PLN |
| CRM reference materials | Certified CFPP standards (PAC / Paragon Scientific) | 1 500–4 000 PLN / set |
Reagents, media and consumables
| Reagent | CAS | Details |
|---|---|---|
| Acetone | 67-64-1 | Analytical grade, for washing wire mesh filters and vessels between determinations |
| Toluene | 108-88-3 | Analytical grade, for dissolving paraffin deposits from filters |
| n-Heptane | 142-82-5 | For rinsing measuring vessels and calibration |
| Refrigerant | — | Refrigerant gas (CFC-free) in apparatus cooling cabinet |
Health and safety (OHS)
- Fuel — flammable, avoid ignition sources around apparatus
- Low temperature (-51°C in chamber) — frostbite risk, use protective gloves
- Toluene, acetone — flammable and irritating, work under fume hood
- Vacuum system — do not aspirate fuel by mouth, use mechanical pump
Frequently asked questions
Which standard describes this test?
The test is performed according to PN-EN 116:2015 — “Diesel and domestic heating fuels — Determination of cold filter plugging point — Stepwise cooling bath method”.
How does this method work?
A diesel fuel sample (45 mL) is cooled stepwise in a thermostatic cooling bath. At 1°C intervals, the sample is aspirated under 1.
What is the measuring range and accuracy?
Wire mesh filter: 45 µm (355 meshes), stainless steel; Aspiration vacuum: 1.96 kPa (200 mm H₂O); Sample volume: 45 mL; Blockage criterion: Flow time of 20 mL >60 s or no flow.
How long does the test take?
The times given for the individual stages add up to approximately 43 min–1 h 23 min. The procedure comprises 9 steps.
What equipment is required?
Automatic CFPP apparatus, Cooling cabinet (4 chambers), 45 µm wire mesh filters, Measuring vessels and pipettes, Reference thermometer, CRM reference materials. Indicative cost of the core instrument (Automatic CFPP apparatus): 60 000–120 000 PLN.
Where is this test used?
Diesel fuel quality certificate — summer/transitional/winter/arctic grade (PN-EN 590); Quality control of FAME and B7/B10/B20 blends (PN-EN 14214); Depressant (CFPP-lowering additive) effectiveness assessment; Seasonal control at fuel depots and fuel stations; Testing of domestic heating oils (PN-EN 14078); R&D research — optimization of winter fuel formulations; Customs control and commercial inspection of fuel quality; Determination of low-temperature properties of paraffinic fuels (GTL, HVO).
What safety precautions apply?
Fuel — flammable, avoid ignition sources around apparatus; Low temperature (-51°C in chamber) — frostbite risk, use protective gloves; Toluene, acetone — flammable and irritating, work under fume hood; Vacuum system — do not aspirate fuel by mouth, use mechanical pump.
Which laboratory can perform this test?
The test is performed by laboratories accredited to ISO/IEC 17025. On LabCoda you can find them by the standard number PN-EN 116.