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 Missouri, speeding in a construction or work zone, also known as a 'Travel Safe Zone,' is a serious offense. The state enforces strict penalties to ensure the safety of workers and drivers in these areas. Missouri law stipulates that drivers must adhere to posted speed limits in construction zones regardless of whether workers are present. The fines for speeding in these zones are significantly higher than for non-construction areas. For the first offense, the fine can be up to $250, and for subsequent offenses, up to $300. Additionally, the Missouri Department of Revenue may assess points against the driver's license, which can lead to increased insurance rates and potential license suspension with the accumulation of points. It's important for drivers to pay close attention to signage indicating the start and end of construction zones to comply with the law and maintain safety.