<Li> The slow lane is the lane nearest to the shoulder of a multi-lane carriageway / roadway . </Li> <Dd> These usages lead to the phrases life in the slow lane and life in the fast lane, used to describe relaxed or busy lifestyles, respectively and used as the titles of various books and songs . </Dd> <P> While in general, wider lanes are associated with a reduction in crashes, in urban settings both narrow (less than 2.8 m) and wide (over 3.1 ~ 3.2 m) lanes increase crash risks . Wider lanes (over 3.3 ~ 3.4 m) are associated with 33% higher impact speeds, as well as higher crash rates . Carrying capacity is also maximal at a width of 3 to 3.1 metres (9.8 to 10.2 ft), both for motor traffic and for bicycles . Pedestrian volume declines as lanes widen, and intersections with narrower lanes provide the highest capacity for bicycles . As lane width decreases, traffic speed diminishes . </P> <P> Advocates for pedestrian and cyclist safety, and many new urbanists disagree with traditional thinking in traffic engineering, saying that safety and capacity are not adversely impacted by reducing lanes widths to as little as 10 feet (3.0 m). Moreover, wider travel lanes also increase exposure and crossing distance for pedestrians at intersections and midblock crossings . </P>

What is the standard width of a two lane road