What is the speed limit when part of a highway traffic lane is closed for construction, maintenance, or surveying, unless otherwise posted?

The speed limit when a part of a highway traffic lane is closed for construction, maintenance, or surveying is typically set at 45 mph, unless otherwise posted. This speed limit is established to ensure safety in work zones where construction workers, equipment, and altered road conditions may pose additional hazards. By maintaining a moderate speed, drivers can better react to sudden changes, such as detours or workers entering the roadway, helping to reduce the risk of accidents in those areas. It is essential for drivers to remain vigilant and aware of any posted signs indicating changes to speed limits in these environments, which may lower the limit further based on specific circumstances or conditions at the work zone.