20.20 May 23, 2025
ISO
ISO/TC 22/SC 34
International Standard
This document specifies the quality characteristics of the NOx reduction agent AUS 32 (aqueous urea solution) which is needed to operate selective catalytic reduction (SCR) converter systems in motor vehicles with diesel engines. SCR converter systems are particularly suitable for selectively reducing the nitrogen oxide (NOx) emissions of diesel engines.
IN_DEVELOPMENT
ISO/WD 22241-1
20.20
Working draft (WD) study initiated
May 23, 2025