Why DEF Refractometer Verification Matters: A Simple Step That Can Prevent Costly Problems

Diesel Exhaust Fluid (DEF) is a critical component of modern Selective Catalytic Reduction (SCR) emissions systems. When DEF quality and concentration are correct, the SCR system can perform as designed. When DEF concentration is outside specification—or when the fluid has been contaminated or degraded—problems can develop that may lead to reduced performance, warning lights, diagnostic faults, downtime and expensive repairs.

One of the simplest ways to monitor DEF concentration is with a refractometer.

But there is an important question that is often overlooked:

How do you know your refractometer is giving you an accurate reading?

That is where a DEF refractometer verification fluid becomes an important part of a good maintenance and quality-control procedure.