The infraction or offense of speeding in a construction or work zone is committed when the driver of a motor vehicle in a marked construction/work zone exceeds the posted speed limit or exceeds the speed limit that is reasonable and prudent under the circumstances or conditions—conditions such as the road (straight, curved, wet, dry, icy, flat, hilly); the weather (clear, foggy, raining, snowing); and the visibility (smoke from a grass fire or a tractor trailer obstructing the view).

Laws vary from state to state and in many states the construction or work zone speed limit only applies when workers are present and the zone is clearly marked with signs. But drivers should be aware that the construction or work zone often extends past where barrels or other barriers have been placed on the road and the reduced speed limit continues to apply until there is a sign indicating an increased speed limit.

Laws regarding speeding in a construction or work zone (and their enforcement) vary from state to state and among cities and towns (local ordinances) and are usually located in a state’s statutes. The penalty for speeding in a construction or work zone is usually a fine and demerit points added to the driver’s license or driving record. But the fines and penalties for speeding in a construction zone are usually much greater than for a typical speeding ticket or citation—for example, fines may be doubled.

In Colorado, speeding in a construction or work zone is considered a serious offense. The state enforces what is known as 'double fine zones' in construction or work zones to deter speeding and enhance the safety of workers and other motorists. This means that if a driver is caught speeding in a marked construction or work zone, the fines are typically doubled compared to those for regular speeding violations. The exact amount of the fine and the number of demerit points added to the driver's license can vary, but the increased penalties are intended to promote caution in areas where road workers are present. It's important for drivers to pay attention to signage indicating the start and end of these zones, as the reduced speed limit applies throughout the entire marked area, regardless of whether workers are visibly present at the time. Additionally, Colorado law requires drivers to obey the posted speed limits and drive according to the conditions of the road and weather, ensuring that their speed is reasonable and prudent for the situation.