The U.S. Environmental Protection Agency has issued new guidance addressing diesel exhaust fluid (DEF) systems. For NATA members, this is a positive step toward improving reliability for diesel-powered ground support equipment (GSE), including refuelers and deicing vehicles.
The guidance allows manufacturers to remove or replace DEF quality sensors that have been a common source of false fault conditions and engine derates. In practice, this should reduce unnecessary downtime and improve equipment availability on the ramp.
What has not changed:
- DEF is still required.
- Selective Catalytic Reduction (SCR) systems remain in place.
- Emissions compliance requirements are unchanged.
Because DEF will continue to be present across airport operations, the associated risks—particularly contamination—remain unchanged.
NATA encourages members to continue following established best practices for DEF handling and contamination prevention, as outlined in OBP-36: Preventing Contamination of FSII with DEF or any Other Product.