Delaware Code
Subchapter XI. Miscellaneous Rules
§ 4191B. Coal rolling is prohibited.

(a) Except as provided in subsection (b) of this section, no person shall retrofit any diesel-powered vehicle with any device, smoke stack, or other equipment that enhances the vehicle's capacity to emit soot, smoke, or other particulate emissions, or shall not purposely release clearly visible quantities of soot, smoke, or other particulate emissions into the air and onto roadways and other vehicles while operating the vehicle, colloquially referred to as “coal rolling.”
(b) This section does not apply to a person operating:

(1) A diesel-powered vehicle that discharges visible exhaust as the result of normal acceleration or towing;
(2) A construction vehicle operating at a construction site.
(c) Any person who violates the prohibition in subsection (a) of this section shall be subject to a penalty of not more than $500 per violation.

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