Shoulder (road)

Many wider freeways, or expressways elsewhere have shoulders on both sides of each directional carriageway—in the median, as well as at the outer edges of the road, for additional safety.

In some cases, particularly on older rural roadways, shoulders that initially existed were hardened with gravel rather than being paved with asphalt, tarmac or concrete.

However, it is extremely unsafe, and in most jurisdictions illegal, to abuse the shoulder by 'undertaking' passing vehicles that are nearer the centre of the road.

As a result, some motorists are unable to fully exit the mainline when they need to pull over, so they end up in a position that is halfway in the rightmost lane and only partly on the shoulder.

[6] The Route 9 BBS in Central New Jersey which runs along two stretches of shoulders are dedicated for exclusive bus use during peak hours.

Active traffic management with special signage, new laybys and a controlled variable speed limit have been put in place to improve safety.

[22] The shoulder-use plan was implemented in place of labour- and resource-intensive contraflow lane reversal, in which both sides of an interstate highway are used for one direction of traffic.

Data collated by the OECD indicates that rural locations account for 35% or more of cycling fatalities in Denmark, Finland, France, Great Britain, Japan, the Netherlands, and Spain.

[32] In some countries, the use of shoulders is optional for cyclists, who may choose not to use it for reasons such as: it being too narrow, inviting dangerously close passes at high speed by motorists; it having a road surface unsuitable for cycling or putting the path of the cyclist in direct conflict with the paths of other road users, such as those turning across the shoulder.

However, no mandatory regulations exist to wear a high-visibility jacket when dismounting from the vehicle stopped in an emergency lane.

A recent study conducted by the National Coroners Information System (NCIS) in Australia[34] has revealed 29 closed case fatalities (and at least a dozen case fatalities still under coronial investigation) that had been reported to Australian coroners where a person was "struck in an emergency lane after their vehicle had stopped" between July 2000 and November 2010.

At some points (tunnel, bridge, narrow road with no shoulder, tight curve) the edge line becomes solid.

On motorways, and at critical points on other routes (e.g. between junctions or interchanges, or beneath overpasses) a solid yellow line is used, denoting additional restrictions on usage of the hard shoulder.

At junctions and on-ramps and off-ramps, the yellow line peels away into the turn, with a dashed white line (with green cats' eyes) denoting a lane division following the main route (i.e. in most cases the road remains the same width, and a turn lane takes the place of the hard shoulder).

However, dedicated bus lanes are now present on sections of some routes, such as the N7 Naas Road, and such use of actual hard shoulder is not universal.

According to the regulation in force, it is mandatory to wear a high visibility jacket when dismounting from a vehicle stopped in an emergency lane.

Hard shoulders are always marked with a reflecting solid white line which is 20 centimetres (7.9 in) wide and is provided with a rumble strip.