A study by the Minnesota Department of Transportation shows that an effective zipper merge can reduce the duration of a ...

Why are so many drivers slow to pick up and use the zipper merge? I have reported for years about the lack of general merging etiquette in the Pacific Northwest and how it contributes to our terrible ...

Nearly 70% of motorists fail to merge in turn correctly at lane closures, new research has revealed. Merging in turn is a traffic management technique enabling multiple lanes to combine, with road ...

I'm unaware of such a law. To my knowledge the sign is informational (especially if it's black-on-yellow) and is there to let you know that lanes will be ending.