BIS approved, made to ISO 22241
The standards our DEF is made and tested to, and the limits every batch has to meet before it ships.
BIS approved
Our Diesel Exhaust Fluid is made to standards approved by the Bureau of Indian Standards, India's national standards body — so you can specify it for your fleet or equipment with confidence.
ISO 22241 compliant
ISO 22241 is the international standard for DEF: its quality, how it's tested, and how it should be handled and stored. Engine makers design their SCR systems around it.
01Specification
The limits in ISO 22241
Our laboratory tests each batch for urea concentration, density, refractive index, alkalinity, biuret and insoluble matter against these limits. A batch that misses one doesn't leave the plant.
Why compliance matters
- The same quality from one delivery to the next.
- SCR systems work as designed, without deposits or fault codes.
- NOx emissions come down as far as they should.
- Expensive SCR parts are protected from contamination.
- A fluid made and checked to recognised standards.
ISO 22241 · Limits
Every batch
- Urea content
- 31.8 – 33.2%
- Density at 20 °C
- 1.087 – 1.093 g/cm³
- Refractive index at 20 °C
- 1.3814 – 1.3843
- Alkalinity (as NH3)
- ≤ 0.2%
- Biuret
- ≤ 0.3%
- Aldehydes (as HCHO)
- ≤ 5.0 mg/kg
- Insoluble matter
- ≤ 20 mg/kg
- Phosphate (PO4)
- ≤ 0.5 mg/kg
Allowed by ISO 22241 32.5% nominal Past the maximum
02Documents
The certificates
The BIS licence for our AUS 32, the ISO 9001:2015 certificate for the quality management system, and the ISO 18611-1 certificate for our marine AUS 40. These are the copies for your records or a tender.
BIS licence
CM/L-8400358713 for AUS 32. Valid to 3 July 2031.
ISO 9001:2015
Certificate 150490326. Valid to 17 March 2029.
ISO 18611-1 · AUS 40
DGCS/Q/0286/1026 for marine AUS 40. Valid to 9 October 2029.
A question about any of them? Email helpdesk@modulx.in
03Lab tests
Independently tested
Two independent laboratories have tested MODULX Genuine D.E.F. against ISO 22241-1. The Central Institute of Road Transport, Pune, graded it "A"; UltraLabs found it normal on every parameter.
CIRT, Pune
Approved, Grade "A". ISO 22241-1:2019, 15 September 2026.
UltraLabs
Normal on every parameter. ISO 22241-1, 29 September 2026.
| Parameter | Limit | CIRT, Pune | UltraLabs |
|---|---|---|---|
| Urea content | 31.8 – 33.2% | 32.1% | 32.1% |
| Density at 20 °C | 1.087 – 1.093 g/cm³ | 1.088 | 1.0893 |
| Refractive index at 20 °C | 1.3814 – 1.3843 | 1.3825 | 1.3826 |
| Alkalinity (as NH3) | ≤ 0.2% | 0.01% | < 0.01% |
| Biuret | ≤ 0.3% | 0.29% | 0.29% |
| Aldehydes | ≤ 5.0 mg/kg | < 0.5 mg/kg | 0.1 mg/kg |
| Insoluble matter | ≤ 20 mg/kg | 4.0 mg/kg | 3.0 mg/kg |
| Phosphate (PO4) | ≤ 0.5 mg/kg | < 0.1 mg/kg | 0.06 mg/kg |
| Metals (Al, Ca, Cr, Cu, Fe, K, Mg, Na, Ni, Zn) | ≤ 0.2 – 0.5 mg/kg each | All within; Ca 0.3 | All within; Ca 0.48 |
As printed in each report. CIRT: sample 2699915100, sent by ASRTU, New Delhi; report ED/26-27/2699915100/AB0972, 15 September 2026; density recorded as 1088 kg/m³. UltraLabs (Ultra Plus Lubes Pvt. Ltd., accredited lab TC-5865): sample MODULX-03; report ULR-TC586526000051808F, 29 September 2026.