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LabCoda / Knowledge Base / Technical Cleanliness of Components (VDA 19.1)

🚗 Technical Cleanliness of Components (VDA 19.1)

Automotive VDA 19.1

In short

Technical cleanliness testing of automotive components via extraction of particulate contaminants with gravimetric and microscopic analysis. The test is performed according to VDA 19.1:2015 (2. wydanie); Particle size classes: 5–15, 15–25, 25–50, 50–100, 100–150, 150–200, 200–400, 400–600, 600–1000, >1000 µm. The procedure comprises 11 steps (about 2 h 45 min–4 h 45 min in total); it is used for: Technical cleanliness control of injection system parts (common rail, injectors), Verification of brake system component cleanliness (ABS, ESP), Testing of steering system component cleanliness (EPS).

At a glance

  • Standard: VDA 19.1:2015 (2. wydanie)
  • Category: Automotive
  • Procedure steps: 11
  • Total time of stages: 2 h 45 min–4 h 45 min
  • Particle size classes: 5–15, 15–25, 25–50, 50–100, 100–150, 150–200, 200–400, 400–600, 600–1000, >1000 µm
  • Gravimetric detection limit: 0.1 mg (analytical balance)
  • Membrane filter porosity: 5 µm (standard), 0.8–8 µm available

Overview

Technical Cleanliness (TC) is a critical quality parameter in the automotive industry. The VDA 19.1 standard, developed by the German Association of the Automotive Industry (Verband der Automobilindustrie), defines uniform methods for testing particulate contamination on functionally relevant vehicle parts. The first edition was published in 2004, the second — revised — in 2015.

Particulate contamination (metallic, non-metallic, fibers) can cause failures in hydraulic, injection, braking, steering, and air conditioning systems. A single metallic particle >200 µm in a common rail system can block an injector and lead to engine damage. Therefore, OEMs (BMW, VW, Daimler, Stellantis) require suppliers to provide documented technical cleanliness in accordance with VDA 19.1.

The test process consists of three stages: extraction of particles from the component surface (rinsing, ultrasound, shaking), filtration of the suspension on a membrane filter, and analysis of particles by gravimetric method (total mass) and/or microscopic method (size distribution, classification as metallic/non-metallic/fibers). Results are compared with limit values established by the customer (so-called CCC — Component Cleanliness Code).

VDA 19.1 is the reference standard in Europe; its international equivalent is ISO 16232. Both standards are technically convergent, although they differ in procedural details. A technical cleanliness laboratory requires a cleanroom of ISO class 7–8 or a dedicated laminar flow cabinet.

Method principle

The test principle is based on controlled extraction of contaminant particles from the surface of the tested component using an extraction liquid (most commonly isopropanol, test naphtha, or aqueous solution with surfactant). Extraction is performed using one or a combination of methods: pressure rinsing (spray rinsing), ultrasonic bath, or agitation. The resulting suspension is then filtered under vacuum through a membrane filter (typically 47 mm, 5 µm porosity). The filter is subjected to gravimetric analysis (weighing on an analytical balance with 0.1 mg accuracy) and microscopic analysis (optical microscope with automatic particle counting or SEM-EDX for chemical composition identification). Results are expressed as CCC — component cleanliness code, indicating the number and size of particles in defined size classes (from 5 µm to >1000 µm).

Applications

Key parameters

ParameterValue
Particle size classes5–15, 15–25, 25–50, 50–100, 100–150, 150–200, 200–400, 400–600, 600–1000, >1000 µm
Gravimetric detection limit0.1 mg (analytical balance)
Membrane filter porosity5 µm (standard), 0.8–8 µm available
Filter diameter47 mm (standard), 25 or 90 mm optionally
Extraction liquid volumeDependent on part surface area, typically 0.5–5 L
Room cleanliness classISO 7–8 according to ISO 14644-1 or laminar cabinet

Standard

Standard number
VDA 19.1:2015 (2. wydanie)
Title (PL)
Kontrola czystości technicznej — Zanieczyszczenie cząstkami stałymi części funkcyjnych w motoryzacji
Title (EN)
Inspection of Technical Cleanliness — Particulate Contamination of Functionally Relevant Automotive Parts

Step-by-step procedure

  1. Workstation preparation

    Check cleanliness of extraction chamber — perform blank test (extraction without component). Particle mass on blank must be <10% of CCC limit value.

    ⏱ Time: 20 min

  2. Extraction liquid preparation

    Prepare appropriate volume of clean extraction liquid (isopropanol, naphtha, or aqueous solution with surfactant) according to test instructions.

    ⏱ Time: 5 min

  3. Particle extraction — rinsing

    Place component in extraction chamber. Rinse all functional surfaces with liquid under controlled pressure (1–4 bar), collecting rinse into container.

    ⏱ Time: 5–15 min

  4. Particle extraction — ultrasound (optional)

    Immerse component in ultrasonic bath with extraction liquid. Parameters: frequency 25–40 kHz, time 5–15 min, temperature 20–40°C.

    ⏱ Time: 5–15 min • 🌡 Temperature: 20–40°C

  5. Decay test

    Repeat extraction 3 times to confirm that procedure removes ≥90% of particles. Mass from subsequent extractions should decrease and third result should constitute <10% of total.

    ⏱ Time: 30–60 min

  6. Suspension filtration

    Filter all collected extraction liquid through 47 mm / 5 µm membrane filter under vacuum. Rinse funnel and container 3× with clean liquid.

    ⏱ Time: 10–20 min

  7. Filter drying

    Dry filter in dryer at temperature 60–80°C for minimum 30 min or to constant mass. Cool in desiccator min. 15 min.

    ⏱ Time: 45–60 min • 🌡 Temperature: 60–80°C

  8. Gravimetric analysis

    Weigh filter on analytical balance (0.1 mg). Calculate particle mass: m = m_after_filtration − m_empty_filter. Subtract blank value.

    ⏱ Time: 5 min

  9. Microscopic analysis

    Place filter under microscope with automatic scanning. System counts particles in size classes, classifies them as metallic (shiny), non-metallic (matte), and fibers.

    ⏱ Time: 15–45 min

  10. Result classification (CCC)

    Convert results to component cleanliness code (CCC) according to VDA 19.1. Compare with limit values established by customer (OEM).

    ⏱ Time: 10 min

  11. Documentation and report

    Prepare test report containing: sample identification, extraction parameters, gravimetric and microscopic results, CCC code, photos of largest particles, compliance assessment.

    ⏱ Time: 15–30 min

Required equipment and apparatus

EquipmentExampleIndicative price
Extraction chamber (spray cabinet)CleanControlling CC-SC, Hydac CTU, JOMESA extraction cabinet80 000–250 000 PLN
Ultrasonic bathBandelin Sonorex DT 1028, Elma S300H5 000–25 000 PLN
Optical microscope with particle analysisJOMESA CleanMaster, Zeiss Axio Imager, Olympus BX53M120 000–400 000 PLN
Analytical balance (0.1 mg)Mettler Toledo MS205DU, Sartorius Quintix 2248 000–25 000 PLN
Vacuum filtration setMerck Millipore, Sartorius, Pall3 000–8 000 PLN
Laminar cabinet / cleanroomWeiss Technik, Spetec, HEPA H1415 000–80 000 PLN
SEM-EDX (optional)Thermo Fisher Phenom XL, Zeiss EVO, JEOL JSM-IT500400 000–1 500 000 PLN

Reagents, media and consumables

ReagentCASDetails
Isopropanol analytical grade67-63-0Extraction solvent, purity ≥99.5%, 2.5–10 L
Test naphtha (Exxsol D40/D60)64742-48-9Hydrocarbon extraction solvent for oiled parts, 5–20 L
Membrane filters 47 mm / 5 µm—Cellulose or nylon, white or with grid, for gravimetric and microscopic analysis, pack of 100
Deionized water with surfactant—Water with conductivity <1 µS/cm with addition of 0.1–0.5% nonionic detergent (e.g., Deconex)
Acetone analytical grade67-64-1For cleaning laboratory equipment, purity ≥99.5%

Health and safety (OHS)

Frequently asked questions

Which standard describes this test?

The test is performed according to VDA 19.1:2015 (2. wydanie) — “Inspection of Technical Cleanliness — Particulate Contamination of Functionally Relevant Automotive Parts”.

How does this method work?

The test principle is based on controlled extraction of contaminant particles from the surface of the tested component using an extraction liquid (most commonly isopropanol, test naphtha, or aqueous solution with surfactant). Extraction is performed using one or a combination of methods: pressure rinsing (spray rinsing), ultrasonic bath, or agitation.

What is the measuring range and accuracy?

Particle size classes: 5–15, 15–25, 25–50, 50–100, 100–150, 150–200, 200–400, 400–600, 600–1000, >1000 µm; Gravimetric detection limit: 0.1 mg (analytical balance); Membrane filter porosity: 5 µm (standard), 0.8–8 µm available; Filter diameter: 47 mm (standard), 25 or 90 mm optionally.

How long does the test take?

The times given for the individual stages add up to approximately 2 h 45 min–4 h 45 min. The procedure comprises 11 steps.

What equipment is required?

Extraction chamber (spray cabinet), Ultrasonic bath, Optical microscope with particle analysis, Analytical balance (0.1 mg), Vacuum filtration set, Laminar cabinet / cleanroom, SEM-EDX (optional). Indicative cost of the core instrument (Extraction chamber (spray cabinet)): 80 000–250 000 PLN.

Where is this test used?

Technical cleanliness control of injection system parts (common rail, injectors); Verification of brake system component cleanliness (ABS, ESP); Testing of steering system component cleanliness (EPS); Control of turbocharger and engine component cleanliness; Validation of industrial washing processes; Supplier audits in the automotive supply chain (Tier 1, Tier 2); Testing of packaging and assembly tool cleanliness; Technical cleanliness control in electromobility (e-drive, batteries).

What safety precautions apply?

Isopropanol and test naphtha — flammable, work away from ignition sources, fume hood; Safety glasses, nitrile gloves, and laboratory coat mandatory; Ultrasound — do not immerse hands in bath during operation, hearing protection during prolonged exposure; Cleanroom — follow entry procedures (protective clothing, airlock); Extraction liquid waste — collect and dispose of according to hazardous waste regulations.

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 VDA 19.1.

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