Editing Traffic warning sign (section)

== Modern traffic warning sign shapes and colors ==
{{Commons|Warning road sign}}
[[File:Road Warning signs around the World.svg|thumb|right|upright=2|alt=Colour-coded political world map (refer to caption)|
{{center|Shape and colors of road warning sign used:}}
{{legend|#FFBE28| Uses [[File:Diamond warning sign.svg|20px|alt=Yellow diamond sign with thin black border]]}}
{{legend|#FF6600| Uses [[File:Diamond warning sign.svg|20px|alt=Yellow diamond sign with thin black border]], previously used [[File:UK traffic sign 500.svg|20px|alt=White triangular (point up) sign with thick red border]]}}
{{legend|#C8141E| Uses [[File:UK traffic sign 500.svg|20px|alt=White triangular (point up) sign with thick red border]]}}
{{legend|#003C8C| Uses [[File:UK traffic sign 500.svg|20px|alt=White triangular (point up) sign with thick red border]], previously used [[File:Triangle warning sign (red and blue).svg|20px|alt=Blue triangular (point up) sign with thick red border]]}}
{{legend|#820082| Uses a combination of [[File:Diamond warning sign.svg|20px|alt=Yellow diamond sign with thin black border]] [[File:UK traffic sign 500.svg|20px|alt=White triangular (point up) sign with thick red border]]}}
{{legend|#2882FF| Uses [[File:Triangle warning sign (red and yellow).svg|20px|alt=Yellow triangular (point up) sign with thick red border]]}}
{{legend|#009664| Uses [[File:Triangle warning sign (black and yellow).svg|20px|alt=Yellow triangular (point up) sign with thick black border]]}}
{{legend|#aaa| No information}}]]
Warning signs can indicate any potential hazard, obstacle or condition requiring special attention. Some of the most common warning signs are the following.

=== General caution ===
[[File:Vienna Convention road sign Ab-32-V1.svg|Yellow diamond with black symbol|thumb|120px|right]][[File:Vienna Convention road sign Aa-32-V1.svg|thumb|100px|left|White background red triangle with black symbol]]
[[File:Vienna Convention road sign Aa-32-V3.svg|thumb|100px|left|Amber background red triangle with black symbol]]

General warning signs are used in instances in which the particular hazard, obstacle or condition is not covered by a standard sign. In Europe, they usually comprise an [[exclamation mark]] on the standard triangular sign ([[Unicode]] {{unichar|26A0|WARNING SIGN}}) with an auxiliary sign below in the local language identifying the hazard, obstacle or condition. In [[Sweden]], the general warning sign has only a vertical line instead of exclamation mark; this model was used also in many other European countries until the 1990s. In the [[United States]] and other countries using diamond-shaped signs, the explanatory language is often written directly on the diamond-shaped sign, although it may contain only a general warning such as "Caution", and pictograms may also be used.

=== Obstacles ===
Warning signs can be placed in advance of, next to or on a specific obstacle. Obstacles such as railway level crossings may have several warning signs beforehand, while bridge ramparts typically have reflective signs placed directly on them on either side. These signs can be specific to the shape requirements of the obstacle, for example, bridge rampart signs are often tall and skinny so as not to intrude into the lane.

=== Curves and corners ===
[[File:Vienna Convention road sign Ab-1b-V1.svg|thumb|120px|left|Vienna Convention dangerous bends sign (diamond-shaped)]]
[[File:New Zealand road sign W12-2.1-L.svg|thumb|120px|left|New Zealand double sharp curve to the left sign]]

These signs indicate that dangerous or unexpected bends in the road are ahead. Signs typically indicate whether the curves are to the right or to the left, the angle of the curve and whether it is one curve or a series of curves.

==== Chevrons and arrows ====
[[File:Philippines road sign HM 1B R.svg|thumb|120px|right|Philippines curve chevron]]

[[Chevron (insignia)|Chevron]]-shaped symbols or arrows on rectangular signs may be placed at the actual location of the bend or curve to further mark the location of the curve and to assist in the negotiation of the curve. They may also be used to indicate "merge" with other traffic, as for an on-ramp of a limited-access [[highway]].
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An unusual occurrence of the rectangular arrow sign appears on the eastbound approach to [[Dead Man's Curve#Ohio|Dead Man's Curve]] in [[Cleveland, Ohio]], US, a curve so sharp that in places an arrow's stem is printed on one sign and the arrow's point is printed on another larger sign further down the road; from the driver's perspective at a distance, the two signs visually blend together to form one large arrow image.

=== Steep hills ===
[[File:Vienna Convention road sign Aa-2a-V1-1.svg|10% down grade sign (white triangle)|thumb|120px|left]]

Truck drivers will need to pay attention to "Steep grade" warnings (or "Down grade, use lower gear"), sometimes posted with the percent grade (e.g., 12%<!-- leave this percent sign - that's what the signs show, not "12 percent" -->). Steep hills may also feature "Runaway truck escape" or "Emergency stop" areas with corresponding signs. The [[United Kingdom|UK]] has a sign warning of "Adverse [[superelevated turn|camber]]" on a curve.

=== Lane starts and ends ===
[[File:Vienna Convention road sign Ab-4b-V1-1.svg|thumb|120px|right|Vienna Convention carriageway narrows sign (yellow diamond)]]

These signs indicate when a multilane highway is being narrowed, when a passing lane is ending, or where the road is widening or a passing lane starting. Another type of sign is used to indicate central "two-way" left turning lane in center of roadway. Warning signs may also warn of "Highway ends", where the road changes class or type.

=== Merge to stay with through traffic ===
[[File:Vienna Convention road sign Ab-19c-V2-1.svg|thumb|120px|left|Vienna Convention merging traffic sign (yellow diamond)]]

In the [[United States]] and [[Canada]], there is special signage for lanes that are about to exit, so that drivers who wish to remain on the main road have adequate time to merge. Such lanes are sometimes indicated by special striping ("alligator stripes") and the sign, "Through Traffic Merge Left" (or right). On freeways, the green directions sign for the exit ramp may have the additional notation, "Exit Only", and should have black letters on a yellow background for emphasis.

=== Bridges ===
[[File:Vienna Convention road sign Aa-5-V1.svg|thumb|120px|right|Vienna Convention [[drawbridge]] ahead sign (white triangle)]]
[[File:New Zealand road sign W13-2.svg|thumb|120px|left|New Zealand narrow bridge ahead sign]]

These signs are used where traffic may be constricted to a narrow bridge, or where the bridge may have a movable span closed to vehicles while boats pass (e.g., [[drawbridge]]). They may also be used for underpass to indicate low overhead clearance.

=== Tunnels ===
[[File:MUTCD-CA SW37.svg|thumb|120px|left|United States (California)]]

These signs are used to indicate [[tunnel]]s, where lights are usually required, and a general change in the light level. May also indicate low [[ceiling]] [[Engineering tolerance|clearance]]. Truck drivers should also watch for prohibited cargo signs (e.g., [[propane]]) upon approach to tunnels.

=== Road conditions ===
[[File:Vienna Convention road sign Aa-34-V1-EA.svg|thumb|upright=0.54|left|Vienna Convention slippery road because ice or snow (white triangle)]]

Warns road users of severe road conditions ("Icy road", "Bump", etc). Also "Loose gravel", "Soft shoulder", "[[Speed hump]]", and "Watch for ice".

=== Falling rocks ===
[[File:Vienna Convention road sign Aa-11a-V1.svg|thumb|120px|right|Vienna Convention falling rocks sign (white triangle)]]

These signs may be used to indicate the hazards of fallen or falling rocks on the road ahead. They are usually pictographs, but may also include wording, such as "falling rocks". In [[Italy]] the words may be "{{lang|it|caduta [[wikt:sassi#Italian|sassi]]}}" or "{{lang|it|caduta massi}}"; in [[France]] "{{lang|fr|chute de pierres}}"; in [[Mexico]] "{{linktext|derrumbe|lang=es}}s".

=== Pedestrian crossings ===
[[File:Vienna Convention road sign Aa-12c-V1.svg|thumb|120px|right|Vienna Convention pedestrian crossing sign (white triangle)]]

These signs are used to warn drivers of people walking in the street. They may also be used to warn of children playing, playgrounds, bicycle area, deaf child, blind pedestrians, and thickly settled zones where pedestrians may enter the road.

In [[California]], [[United States]] near the [[Mexican border (US)|Mexican border]], there were [[Immigration sign|warning signs showing a running family]]. This was to warn motorists to look out for [[Illegal immigration|illegal immigrants]] who try to escape [[United States Border Patrol|authorities]] by running through freeway traffic. The symbol was created by [[California Department of Transportation]] employee John Hood in the late 1980s.<ref>{{Cite news |last=Berestein |first=Leslie |date=April 10, 2005 |title=Highway Safety Sign Becomes Running Story on Immigration |work=SignOnSanDiego.com |url=http://www.signonsandiego.com/uniontrib/20050410/news_1n10signs.html |url-status=dead |access-date=2006-07-14 |archive-url=https://web.archive.org/web/20060628040209/http://www.signonsandiego.com/uniontrib/20050410/news_1n10signs.html |archive-date=2006-06-28}}</ref>

=== Schools ===
[[File:Vienna Convention road sign Ab-13-V1-LHT.svg|thumb|120px|left|Vienna Convention school crossing ahead (yellow diamond, LHT version)]]

These signs mark school zones (in which lower speed limits may be in place), student crossings, crossing guards or signals ahead. In the U.S. and Canada, pentagon-shaped signs are used in place of the usual diamond-shaped signs. The shape of the U.S. school zone resembles a [[one-room schoolhouse]] and is the only U.S. sign shaped this way. Some Canadian provinces use an identical sign.

=== Bicycles ===
[[File:Vienna Convention road sign Aa-14-V1.svg|thumb|120px|right|Vienna Convention bicycle crossing ahead (white triangle)]]

Bicycle crossing signs warn that bicycles will cross at their location.

=== Animals crossing the roadway ===
[[File:Vienna Convention road sign Ab-15b-V1-LHT.svg|thumb|120px|right|Vienna Convention wild animal crossing (yellow diamond, LHT version)]]
[[File:New Zealand road sign W18-3.1.svg|thumb|120px|left|New Zealand cows ahead sign]]
[[File:New Zealand road sign W18-3.2.svg|thumb|120px|left|New Zealand sheep ahead sign]]
[[File:MUTCD W11-17.svg|thumb|120px|right|U.S. sheep area sign]]

These signs warn of animals that may stray onto the road. They can be either wild (as with deer or moose) or farm animals (as with cows or ducks). In the United States, a "share the road" plaque is sometimes placed below these warning signs when used in this manner.

=== Unusual vehicles in roadway ===
[[File:UK traffic sign 582.svg|thumb|left|120px|United Kingdom: military vehicles crossing.]]
[[File:New Zealand road sign W18-5.svg|thumb|left|120px|New Zealand: fire trucks.]]

These signs are found where road users can encounter slow, large or non-typical vehicles such as forklifts, handcarts and military vehicles. They are more common around quarries, airports, industrial zones, military installations and rural areas.

=== Road work or construction ===
[[File:New Zealand road sign W1-1A.svg|thumb|120px|right|New Zealand road work sign]]

These signs are often temporary in nature and used to indicate road work (construction), poor roads, or temporary conditions ahead on the road including flagmen, uneven pavement, etc. (Note that some "high water" signs are posted to alert drivers of a flood-prone area and do not actually mean that there is a flooded section of road ahead.) In France, Italy, Spain, Norway etc., warning (and speed limit) signs connected with road work have a yellow background in place of the usual white background on signs. In North America and Ireland, signs connected with road work have an orange background.

=== Traffic signals ===
[[File:Vienna Convention road sign Aa-17a-V1.svg|thumb|120px|left|Vienna Convention traffic signal ahead (white triangle)]]

These warning signs indicate that [[Traffic signal|traffic lights]] are ahead, and are often used when it is difficult to see that a traffic light may already be showing red, to warn a driver to prepare to slow down. They may be supplemented with flashing light or lighted sign when light is red or turning red. Some countries also have signs warning of signals for [[ramp meter]]s, fire stations, and airfields.

=== Intersections ===
[[File:Vienna Convention road sign Ab-18b-V1.svg|thumb|120px|left|Vienna Convention intersection sign (diamond-shaped)]]
[[File:NZ road sign W11-2.svg|thumb|120px|left|New Zealand intersection with priority sign]]

These signs warn of road crossings at crossroads, T-intersections, roundabouts, or Y-intersections. They may also indicate "hidden driveway" intersecting the road ahead. (Compare with bridges, [[overpass]]es, [[viaduct]]s).

=== Warning signs for regulatory signs ===
[[File:Vienna Convention road sign Aa-21a-V1.svg|thumb|120px|right|Vienna Convention stop ahead sign (white triangle)]]
[[File:NZ road sign W10-1.svg|thumb|120px|left|New Zealand stop ahead sign]]
[[File:NZ road sign W10-2.svg|thumb|120px|left|New Zealand give way ahead sign]]

Like for traffic signals, some [[stop sign|"stop"]] or [[yield sign|"yield" sign]]s may require additional warning or reminder, especially in dense areas or where the sign has been added recently.

=== Oncoming traffic ===
[[File:Vienna Convention road sign Aa-23-V1.svg|thumb|120px|right|Vienna Convention two-way traffic sign (white triangle)]]

These signs may be used to warn people of oncoming traffic; shown when a [[motorway]] becomes a [[dual carriageway]] or a normal road without a [[central reservation]] or median.

=== Level crossing (railway crossing) ===
[[File:Vienna Convention road sign Ab-25-V1.svg|thumb|120px|left|Vienna Convention protected level crossing sign (yellow diamond)]]

These signs are used to warn of [[level crossing]]s ahead. In most countries, a red triangle warning sign is used, with various pictograms for unguarded crossings, crossings with manual gates, and automatic level crossings. In most of Europe, an old-style gate is used for a crossing with gates, and a [[steam locomotive]] for a crossing without gates. Germany uses an electric train. Similar pictograms are also used in Ireland, albeit on an amber diamond sign. In the [[United States]] the warning of all types of railway crossings is made using a circular yellow sign. The actual crossing is also marked with crossed "railroad crossing" [[crossbuck]] signs (stop, look, listen) and possibly lights, bells, and [[boom barrier|barrier]]s.

=== Low flying aircraft ===
[[File:Vienna Convention road sign Aa-30-V1-1.svg|thumb|120px|left|Vienna Convention low flying aircraft (White triangle)]]

A warning sign with the image of an aircraft in the middle of it indicates an airport or airfield, where drivers should be prepared for low-flying aircraft.

=== Crosswinds or side winds ===
[[File:Vienna Convention road sign Aa-31-V1-3.svg|thumb|120px|right|Vienna Convention side winds sign (amber triangle)]]

Flying socks, as indicated in Poland by a [[windsock]] on red triangle or yellow diamond signs, indicate locations where a strong side wind may cause the trajectory of the moving vehicle to change drastically, perhaps even "flying" across lanes, causing an accident.

=== Roads with one entry point ===
[[File:British Columbia G-075.svg|thumb|120px|right|Canada: pictorial no exit sign]]

Roadways that only have one entry/exit point - "[[cul-de-sac|dead end]]", "not a through street" or "no outlet".

=== End of roadway ===
[[File:NYCDOT W14-5.SVG|thumb|120px|left|U.S. (New York City): roadway ends.]]
Signs indicating the end point of a [[roadway]].

=== Fire stations ===
[[File:MUTCD-TX W11-12T.svg|thumb|120px|left|Texas emergency vehicles sign]]

These signs warn of approach to where [[firefighter]]s may be entering the road with [[fire apparatus|fire engines]] or other emergency apparatus, where other drivers will have to stop and wait until they pass.