This bill introduces a new section to RSA 265, specifically section 75-a, which prohibits the operation of diesel-powered motor vehicles with a manufacturer's gross vehicle weight rating under 18,000 pounds if they emit visible smoke on public ways or parking areas due to alterations in the exhaust or emission control systems, commonly referred to as "rolling coal." Violators of this provision will be subject to penalties classified as a violation. The bill is set to take effect on January 1, 2026.

In terms of fiscal impact, the bill is expected to have indeterminable effects on state and local expenditures due to potential changes in the judicial and correctional systems, which may arise from the enforcement of the new penalties. However, there are no anticipated changes in revenue for the state or counties as a result of this legislation. The bill aims to address environmental concerns related to diesel emissions while also establishing a legal framework for enforcement against non-compliance.