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QUALITY

Quality you can trust

DEF works only when it is pure. A tiny amount of contamination can damage an SCR catalyst, so we check quality at every stage, from the raw material we buy to the pack we seal.

  • ISO 22241 is the standard we make and test to.

  • Every batch is tested in our in-house lab before filling.

  • Batch records are kept so any pack can be traced.

OUR PROCESS

Quality at every stage

Raw material testing

Urea and water are checked before they enter production.

In-process checks

Concentration is monitored while the solution is blended.

Finished product testing

Each batch is tested in our lab before it is filled.

Clean filling

Packs are filled and sealed to keep contamination out.

Batch records

Results are recorded so every batch can be traced.

WHAT WE TEST

The ISO 22241 limits

These are the limits ISO 22241 sets for DEF. Each one protects a different part of the SCR system.

Urea contentISO 22241 limit31.8 – 33.2 %Why it mattersThe right strength for the catalyst to work and for the sensor to accept it.
Density at 20 °CISO 22241 limit1087 – 1093 kg/m³Why it mattersA quick check that the concentration is correct.
Refractive index at 20 °CISO 22241 limit1.3814 – 1.3843Why it mattersA second, precise check on concentration.
Alkalinity as NH₃ISO 22241 limit≤ 0.2 %Why it mattersShows the urea has not broken down in storage.
BiuretISO 22241 limit≤ 0.3 %Why it mattersToo much leaves deposits that block the injector.
AldehydesISO 22241 limit≤ 5 mg/kgWhy it mattersImpurities from low-grade urea.
Insoluble matterISO 22241 limit≤ 20 mg/kgWhy it mattersParticles that can clog filters and nozzles.
Phosphate (PO₄)ISO 22241 limit≤ 0.5 mg/kgWhy it mattersCoats and weakens the catalyst.
Ca, Fe, Na, K, Mg, AlISO 22241 limit≤ 0.5 mg/kg eachWhy it mattersMetals that permanently poison the catalyst.
Cu, Zn, Cr, NiISO 22241 limit≤ 0.2 mg/kg eachWhy it mattersTrace metals, held to an even tighter limit.

Limits as set by ISO 22241-1.

AFTER IT LEAVES US

Keeping it pure until it's used

Quality doesn't stop at our gate. A few simple habits keep DEF in spec until it reaches the tank.

  • Sealed packs

    Check the seal is intact when you receive a pack.

  • Out of the sun

    Store below 30 °C, away from direct sunlight.

  • Dedicated equipment

    Use funnels and cans only for DEF, never for fuel or oil.

  • Note the batch number

    Quote it if you ever have a question about a pack.

Have a quality question?

Ask our team about testing, batches or specifications.

Contact us