EPA did not require unique dispenser nozzles for 15 ppm diesel fuel. This is something we considered on several occasions, but concluded, after discussions with the relevant stakeholders that misfueling would not likely be significant enough to justify the cost and burden of the vehicle and fuel pump changes.

The nonroad diesel rule includes labeling requirements for fuel dispensers and vehicles to help prevent misfueling. The fuel dispenser labeling requirements finalized in the highway diesel rule were superceded by those in the nonroad diesel rule (see 40 CFR 80.570, 80.571, 80.572, 80.573, & 80.574).

Question and Answer was originally posted at Questions and Answers on the Clean Diesel Fuel Rules (PDF)(135 pp, 888 K, EPA420-B-06-010, July 2006, About PDF)