Warning sign - wikipedia Warning sign `` Warning Sign '' redirects here. For other uses, see Warning Sign ( disambiguation ). For a sign on a vehicle or building relating to it or its contents, see placard. This article has multiple issues. Please help improve it or discuss these issues on the talk page. ( Learn how and when to remove these template messages ) This article may be in need of reorganization to comply with Wikipedia 's layout guidelines. Please help by editing the article to make improvements to the overall structure. ( December 2017 ) This article may have too many section headers dividing up its content. Please help improve the article by merging similar sections and removing unneeded subheaders. ( December 2017 ) This article possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. ( December 2017 ) This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. ( December 2017 ) Some of this article 's listed sources may not be reliable. Please help this article by looking for better, more reliable sources. Unreliable citations may be challenged or deleted. ( December 2017 ) This article may be too long to read and navigate comfortably. The readable prose size is 14 kilobytes. Please consider splitting content into sub-articles, condensing it, or adding or removing subheadings. ( December 2008 ) Exhibit mostly of warning signs ( with some regulatory signs like Do Not Enter ), Turin Automobile Museum A warning sign is a type of traffic sign that indicates a hazard ahead on the road that may not be readily apparent to a driver. While designs vary, they usually take the shape of an equilateral triangle with a white background and thick red border. In the People 's Republic of China ( except for Macau and Hong Kong ), they appear with a black border and a yellow background. In Sweden, Serbia, Bosnia and Herzegovina, Greece, Finland, Iceland, the Republic of Macedonia and Poland, they have a red border with an amber background. The polar bear warning sign in Svalbard recently changed from displaying a black bear on white background to a white bear on black background ( both signs are triangular with a red border ). Some countries ( like France, Norway and Spain ) that normally use a white background have adopted an orange or amber background for road work or construction signs. Warning signs in some countries have a diamond shape in place of the standard triangular shape. In the United States, Canada, Mexico, Thailand, Australia, Japan, Indonesia, Malaysia, New Zealand, most of South America, and also Ireland ( diverging from the standards of the rest of Europe ) use warning signs are black on a yellow background and usually diamond - shaped, while temporary signs ( which are typically construction signs ) are black on an orange background. Some other countries also use these standards for some signage. The warning signs usually contain a symbol. In Europe they are based on the UNECE Vienna Convention on Road Signs and Signals. In the United States they are based on the MUTCD standard and often contain text only. Contents 1 History 2 Modern warning sign shapes and colors 2.1 General caution 2.2 Obstacles 2.3 Animals crossing the roadway 2.4 Unusual vehicles in roadway 2.5 Road work or construction 2.6 Curves and corners 2.6. 1 Chevrons and arrows 2.7 Tunnels 2.8 Bridges 2.9 Traffic signals 2.10 Warning signs for regulatory signs 2.11 Intersections 2.12 Lane starts and ends 2.13 Merge to stay with through traffic 2.14 Roads with one entry point 2.15 End of roadway 2.16 Pedestrian crossings 2.17 Schools 2.18 Bicycle 2.19 Other signs with unprotected people 2.20 Fire stations 2.21 Oncoming traffic 2.22 Level crossing ( railway crossing ) 2.23 Falling rocks 2.24 Other warnings ( aircraft - related ) 2.25 Crosswinds or Side winds 2.26 Road conditions 2.27 Miscellaneous 3 Warning signs with lights 4 Non-traffic warning signs 5 See also 6 Note History 17th - century sign along Salvador Street in Alfama, Lisbon says `` Year of 1686. His Majesty commands all coaches, seges and litters coming from Salvador 's entrance to back up to the same part '' British specimen, c. 1860s. Early Czech warning signs, c. mid-1930s. The blue signs were later supplanted with red - white - black signs. Pre-standardization British School Zone with metal - cutout generic Warning symbol embellished with red glass reflector - spheres. Some of the first roadside signs -- ancient milestones -- merely gave distance measures. Hazard warnings were rare though occasional specimens appeared, such as the specific warning about horse - drawn vehicles backing up which was carved in stone in Lisbon 's Alfama neighborhood in 1686. The early signs did not have high - contrast lettering and their messages might have been easily overlooked. Signs were written in the local language ( example ) ; symbolic signs, though long used on certain tradesmen 's signs ( like the pawnbrokers ' tri-ball symbol ) were to be used for traffic only much later in history. Complex signage systems emerged with the appearance of motorcars. In 1908 the automobile association in West London erected some warning signs. In 1909, nine European governments agreed on the use of four pictorial symbols, indicating bump, curve, intersection, and railroad crossing. The intensive work on international road signs that took place between 1926 and 1949 eventually led to the development of the European road sign system. As the 20th century progressed, and traffic volume and vehicle speeds increased, so did the importance of road sign visibility. Earlier flat - painted signs gave way to signs with embossed letters, which in turn gave way to button copy signs -- round retroreflective `` buttons '' helped to achieve greater night visibility. Flat metal signs reappeared in the 1980s with the widespread use of surfaces covered with retroflective sheeting materials like Scotchlite. In Europe, the 1968 Vienna Convention on Road Signs and Signals ( which became effective in 1978 ) tried, among other things, to standardize important signs. After the fall of the Iron Curtain and greater ease of country - to - country driving in the Eurozone, European countries moved toward lessening the regional differences in warning signs. In modern regulations, U.S. warning signs are classified as Series W signs, such as : W1 Series ( curves and turns ), W2 Series ( intersections ), W22 Series ( blasting ), et cetera, ending with the W25 Series ( concerning extended green traffic lights ). Some U.S. warning signs are without category while others like the warning stripes at tunnel portals or plain red End of Roadway signs are classified as Object Markers ( OM Series ). In the U.S., Stop and speed limit signs fall under the R Series ( Regulatory ). Modern U.S. signs are widely standardized ; unless they are antique holdovers from an earlier era, oddities like a yellow Stop sign or a red Slippery When Wet sign would typically appear only on private property -- perhaps at a hospital campus or in a shopping mall parking lot. Street sign theft by pranksters, souvenir hunters, and scrappers has become problematic : removal of warning signs costs municipalities money to replace lost signs, and can contribute to traffic collisions. Some authorities affix theft - deterrence stickers to the back sides of signs. Some jurisdictions have criminalized unauthorized possession of road signs or have outlawed their resale to scrap metal dealers. In some cases, thieves whose sign - removal lead to road fatalities have been charged with manslaughter. Artistically inclined vandals sometimes paint additional details onto warning signs : a beer bottle, a handgun, or a boom box added to the outstretched hand of the Pedestrian Crossing person, for example. Modern warning sign shapes and colors Warning signs can indicate any potential hazard, obstacle or condition requiring special attention. Some of the most common warning signs are the following. Most common designs Diamond - shaped with yellow background and black border Triangular with red border and white background Triangular with red border and yellow background Triangular with black border and yellow background Less common designs Diamond - shaped with orange background and black border Diamond - shaped with fluorescent green background and black border Diamond - shaped with fluorescent pink background and black border Diamond - shaped with black background and yellow border Triangular with red border and blue background Red upward - pointing triangle Pentagon with yellow background and black border Pentagon with fluorescent green background and black border Pentagon with blue background and white border Circular with yellow background ( Railroad Crossing ) Rectangular shape with yellow background ( Exit, reduce speed ) World map of typical designs in use Color indicates prevalent type of warning signs in use ( click for large image and detailed info key ). General caution 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 # 9888 : ⚠ ) with an auxiliary sign below in the local language identifying the hazard, obstacle or condition. In 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. Belgium Chile China Finland France Germany Ireland Italy Jamaica Japan New Zealand Norway Panama, Peru, Venezuela Poland Russia South Korea Sweden Thailand United Kingdom Ukraine Obstacles Diamond - shaped with reflectors are placed at point of curbs, dividers, or other lane obstacles. Rectangular signs with diagonal stripes indicate solid objects such as barricades, bridge abutments, utility poles or natural obstacles near the roadway. Left side obstacles are marked with stripes running high to low, left to right ; right side obstacle signs use stripes running high to low, right to left ; in a sense akin to International symbol of arrow pointing down toward side toward roadway. New Zealand and U.S. road diverges / splits Philippines dual carriageway ahead sign U.S. and Canada divided road ahead sign Alternate U.S. divided highway ahead sign U.S. divided road ahead sign New York State pass left or right of obstacle sign United Kingdom, Nepal, Hong Kong, Singapore `` end of dual carriageway '' sign Australian Divided road ahead sign Australia end divided road sign Animals crossing the roadway These signs warn of wild animals ( moose, bear, elk, deer, reindeer, polar bears, camels, wallabies, kangaroos, alligators, etc. ) or farm animals ( cows, horses, ducks, sheep ) that may stray onto the road. In the United States, a `` share the road '' plaque is sometimes placed below these warning signs when used in this manner. Kangaroo crossing sign in Australia Philippines cattle crossing sign Brazil wild animals sign Japan animals crossing Italy, Germany, Latvia and Sudan wild animal crossing sign UK wild fowl warning sign Russia cattle crossing sign Russia wild animal crossing sign Camel warning sign in the UAE A sheep warning sign in the UK Norway moose crossing sign Norway reindeer crossing sign Norway polarbear warning ( Only on Svalbard ) Wild elephant zone - Surin, Thailand UK horse riders warning sign Moose sign from Sweden Swedish sheep crossing Reindeer crossing sign from Sweden Swedish horse crossing Swedish horse riders warning sign China : farm animals crossing Germany : ducklings New Zealand : kiwi crossing New Zealand : kiwi zone at night U.S. and Canada deer crossing sign U.S. cattle crossing sign Caltrans migrating bears sign Pennsylvania duck crossing sign New Zealand : Equestrians Sheep ( New Zealand ) U.S. bear zone U.S. bighorn sheep crossing U.S. moose area U.S. sheep crossing Germany : amphibious animals area Australia : cassowary crossing Unusual vehicles in roadway Also equipment ( tractors, forklifts, snowmobiles, Amish buggies etc. ) crossing or traveling along the road. Taiwan : handcarts crossing. U.K. horse - drawn vehicle ahead warning sign. U.K. military vehicles crossing warning sign. Pennsylvania tank crossing warning sign. Sweden horse - drawn vehicle ahead warning sign. Sweden snowmobile crossing sign. U.S. tractor / farm vehicle crossing warning sign. New York State motorcycle crossing warning sign. New York State ATV crossing warning sign. Ohio golf cart crossing warning sign. Ohio horse - drawn vehicle ahead warning sign. Horse - drawn vehicle ahead, Ohio. Canada logging truck crossing warning sign. Canada ATV crossing warning sign. Canada snowmobile crossing sign. Road work or construction 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, survey crew, single - lane, detour, bridge out, utility crew ahead, blasting area, bump, dip, frost heaves, flooding ( with signs labeled `` High water '' ), soft shoulder, uneven pavement, freshly oiled road, loose gravel, smoke on road, trucks entering, 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 yellow background, these countries normally have white background on signs. In America and Ireland, signs connected with road work have orange background. New Zealand road work sign Brazil road work sign. Ireland road work sign. Jamaica road work sign Austria and Turkey road works sign. Italy construction sign. Norway road work sign. Swedish road work sign. France construction sign. Poland construction sign. Thailand construction sign. Ukraine road work sign. UK road work sign. UK loose chippings warning sign. Netherlands and Turkey loose chippings warning sign. Norway loose chippings sign. Poland loose chippings sign. New Zealand loose chippings sign. Singapore works access ahead sign Singapore heavy vehicles turning ahead sign Canada construction ahead sign. U.S. road work ahead sign. U.S. road work ahead sign, metric version. U.S. and Canada Workers on the road sign. New York State bridge closed ahead sign. Caltrans traffic fines doubled in work zones sign. New York State increased enforcement area work zone sign. Temporary road closure signs in Los Angeles. Curves and corners These signs indicate that ahead are dangerous or unexpected bends in the road, some being continuous, others being sharp - ended. Signs may indicate whether the curves are to the right or to the left and whether the degree to which the curves or bends are sharp. They may also indicate a series of curves or bends ahead. Brazil sharp turn sign Brazil curve sign Chile curve sign Chile sharp turn sign Colombia sharp turn sign Colombia curve sign Indonesia and Thailand left curve sign Malaysia left curve sign Mexico sharp curve ahead sign Mexico sharp turn ahead sign Mexico sharp reverse curves ahead sign Mexico sharp reverse turns ahead sign Mexico winding road ahead sign Panama and Peru sharp turn sign Panama and Peru curve sign Philippines sharp turn ahead sign Philippines sharp reserve turns ahead sign Philippines sharp curve ahead sign Philippines sharp reserve curves ahead sign Philippines winding road ahead sign Saudi Arabia right bend Uruguay sharp turn sign Uruguay curve sign U.S. and Canada sharp turn ahead sign U.S. turn to the right sign, with advisory speed limit U.S. and Canada sharp curve ahead sign U.S. curve to the right sign, with advisory speed limit U.S. and Canada sharp reverse turns ahead sign U.S. and Canada sharp reverse curves ahead sign U.S. and Canada winding road ahead sign U.S. side road junction on a curve sign U.S. crossroad on a curve sign U.S. side road junction on a curve sign U.S. side road junction on a curve sign U.S. side road junction on a double curve sign U.S. crossroad on a double curve sign U.S. and Canada hairpin curve ahead sign California reverse turns ahead sign, with advisory speed limit Quebec hairpin curve ahead sign UK left bend ahead France right curve sign Netherlands bend to right Norway right bend New Zealand fish hook curve to the left sign New Zealand 90 and 120 degrees curve to the left sign Australia sharp turn ahead sign Australia sharp curve ahead sign Australia sharp reverse curves ahead sign Australia winding road ahead sign Ireland sharp corner ( Advisory speed < 50 km / h ) Ireland curve sign ( Advisory speed > 45 km / h ) Malaysian two dangerous curve on the left sign India curve to right sign India curve to left sign Austria and Turkey left curve sign Sweden and Greece curve to the left sign Poland curve to left sign Ireland double bend China double bend Poland double bend UK double bend Norway double bend Italy, Latvia, Sudan double bend Ireland series of curves ( winding road ) Chevrons and arrows 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 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. An unusual occurrence of the rectangular arrow sign appears on the eastbound approach to Dead Man 's Curve in Cleveland, Ohio, USA, 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. Philippines curve chevron U.S. and Canada curve chevron Quebec curve chevron Norway curve chevrons Sweden curve chevrons Russia curve chevrons Singapore chevron signs France curve chevrons Australia curve chevron New Zealand curve chevrons with advisory speed limit France curve chevrons France ring of chevrons in traffic circle hub Switzerland curve chevrons U.S. curve arrow Canada curve arrow Quebec curve arrow U.S. curve arrow ( vandalized with gunfire ) Tunnels The signs are used to indicate tunnels, where lights are usually required, and a general change in the light level. May also indicate low ceiling clearance. Truck drivers should also watch for prohibited cargo signs ( e.g., hazmat, propane, explosives ) upon approach to tunnels. United States ( California ) Czech Republic Jamaica Norway Russia Singapore South Korea Sweden Taiwan United Kingdom New Zealand Bridges 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 or floating bridge ). They may also be used for underpass to indicate low overhead clearance. Philippines narrow bridge warning sign U.S. narrow bridge warning sign U.S. narrow bridge warning sign ( alternative ) U.S. one lane bridge warning sign India narrow bridge warning sign Jamaica narrow bridge warning sign New Zealand narrow bridge warning sign ( one way bridges also have priority signs ) Italy drawbridge ahead sign Russia and Latvia drawbridge ahead sign UK drawbridge ahead sign Czech Republic drawbridge ahead sign Norway drawbridge ahead sign Ontario and Quebec bridge warning sign Canada and Australia narrow bridge warning sign Quebec deer - proof bridge warning sign Singapore height prohibition ahead sign 4.5 m ( 15 ft ) U.S. sign. 3.8 m ( 12 ft 6 in ) Ireland bridge height sign 4.65 m ( 15.3 ft ) New Zealand underpass height sign 3.82 m ( 12.5 ft ) New York State restricted - weight bridge ahead sign 5 short tons ( 4.5 t ) Traffic signals These warning signs indicate that 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 meters, fire stations, and airfields. Australia Belgium Botswana, Lesotho, Namibia, South Africa, Swaziland, Tanzania Brazil Chile, Venezuela China Colombia, Panama, Peru France Germany, Saudi Arabia Indonesia Ireland Italy : vertical traffic signal ahead Italy : horizontal traffic signal ahead Japan Malaysia Mexico Netherlands New Zealand Norway Philippines Poland South Korea Spain Thailand United Kingdom, Hong Kong, Singapore, Dominica, Saint Kitts and Nevis United States, Canada, Dominican Republic, Jamaica United States : alternative United States : ramp meter ahead Uruguay Warning signs for Regulatory signs As for traffic signals, above, some `` stop '' or `` yield '' signs may require additional warning or reminder, especially in dense areas or where the sign has been added recently. Australia stop sign ahead Australia give way sign ahead Jamaica stop ahead sign Jamaica give way ahead sign New Zealand stop ahead sign New Zealand give way ahead sign New Zealand speed limit ahead sign Philippines stop sign ahead Philippines give way sign ahead U.S. and Canada stop sign ahead U.S. stop sign ahead ( alternative ) U.S. and Canada yield ahead sign U.S. yield sign ahead ( alternative ) U.S. speed zone ahead U.S. speed zone ahead ( alternative ) U.S. school speed zone ahead Canada speed zone ahead Germany stop sign ahead China stop sign ahead Intersections These signs warn of road crossings at ( crossroads, T - intersection, forks ( Y - intersection ), rotary / roundabout ). They may also indicate `` hidden driveway '' intersecting the road ahead. ( Compare with bridges, overpasses, viaducts ). Australia, New Zealand and Ontario crossroads ahead sign Australia and New Zealand crossroads from the left sign Australia, New Zealand and Ontario side road intersection on left sign Australia and New Zealand junction at corner with a minor road sign Australia T - intersection ahead sign Australia and New Zealand junction at corner with a minor road sign Brazil crossroads sign Brazil side road sign Brazil oblique side road sign Chile crossroads sign Chile side road sign Colombia crossroads sign Colombia side road sign Colombia oblique side road sign Jamaica crossroad sign Jamaica side road sign Jamaica T - intersection sign Jamaica priority crossroad sign Panama crossroads sign Panama side road sign Panama oblique side road sign Peru crossroads sign Peru crossroads with minor road ahead sign Peru major road ahead sign Peru side road sign Peru side road with minor road sign Peru oblique side road sign Philippines crossroads ahead sign Philippines priority crossroads ahead sign Philippines side road ahead sign Philippines priority side road ahead sign Philippines oblique side road ahead sign Philippines T - intersection ahead sign Philippines Y - intersection ahead sign Saudi Arabia crossroads sign Uruguay crossroads sign Uruguay side road sign UK crossroads ahead sign Norway crossroads ahead sign Japan crossroads sign Italy, Latvia and Sudan crossroads with right - of - way from the right sign Italy, Latvia and Sudan junction with a minor side - road sign Italy, Latvia and Sudan junction with a minor cross road sign Swedish intersection with minor side - road sign Swedish intersection with minor cross road sign Norway intersection with minor cross road sign Ireland crossroads with a major road sign Ireland junction with a minor side - road sign Ireland junction at corner with a minor road sign Ireland junction at a bend with a minor road sign Ireland junction with dual - carriageway sign U.S. and Canada intersection ahead sign U.S. and Canada intersection ahead sign U.S. and Canada intersection ahead sign U.S. and Canada intersection ahead sign U.S. and Canada intersection ahead sign Hidden intersection, Delaware Roundabouts / rotaries Australian and New Zealand roundabout ahead sign Brazil roundabout sign Chile roundabout sign Colombia roundabout sign Jamaica roundabout sign Panama roundabout sign Peru roundabout sign Philippines roundabout ahead sign Uruguay roundabout sign Ireland roundabout ahead sign Finland roundabout sign Norway roundabout sign Roundabout ahead sign in Poland UK large roundabout ahead sign Italy, Latvia and Sudan roundabout ahead sign U.S. and Canada roundabout / traffic circle ahead sign U.S. traffic circle ahead sign Lane starts and ends 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. Philippines road narrow sign U.S. and Canada right lane ends sign Brazil road narrows on both sides sign Japan lane decrease sign Taiwan : right lane ends ahead Italy, Latvia and Sudan road narrows from the right Norway road narrows on both sides UK road narrows on both sides ahead sign Australia road narrow sign Canada and New York State one lane road ahead sign New York State one lane road ahead sign Massachusetts lane drop ahead Merge to stay with through traffic 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. Australia and New Zealand merging traffic sign Brazil merging traffic sign Chile merging traffic sign Colombia merging traffic sign Panama, U.S. and Canada merging traffic sign Peru merging traffic sign Philippines merging traffic sign Uruguay merging traffic sign U.S. and Canada Added Lane traffic sign Caltrans W74 all traffic merge left sign Japan join sign Germany merge with through traffic sign Italy merge from right sign Roads with one entry point Roadways that only have one entry / exit point - `` dead end '', `` not a through street '' or `` no outlet ''. New Zealand : No exit Australia and Philippines : No through road U.S. dead end sign U.S. `` no outlet '' sign Pennsylvania No Through Street sign Pennsylvania loop street sign New York City : dead end Canada : cul - de-sac sign Canada : `` no exit '' sign Jamaica no through road sign End of roadway Canada U.S. ( New York City ) : roadway ends. U.S. roadway ends here ( aka the `` red splat '' ). Pedestrian crossings The 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, there are warning signs showing a running family. This is to warn motorists to look out for illegal immigrants who try to escape authorities by running through freeway traffic. The symbol was created by California Department of Transportation employee John Hood in the late 1980s. Australia pedestrian sign Philippines pedestrian sign Philippines slow down pedestrian crossing ahead sign Botswana, Lesotho, Namibia, South Africa, Swaziland and Tanzania pedestrian crossing sign Botswana, Lesotho, Namibia, South Africa, Swaziland and Tanzania pedestrian sign Indonesian pedestrian crossing sign Ireland pedestrian sign Malaysia pedestrian sign UK zebra crossing ahead sign France pedestrian crossing sign Netherlands pedestrian crossing sign Norway pedestrian crossing sign Thailand pedestrian crossing sign Brazil pedestrian sign UK pedestrians on road ahead sign Poland pedestrian crossing ahead sign Sweden pedestrian crossing sign ( Used to warn ahead ) Russia pedestrian crossing sign Australia : crosswalk ahead U.S. and Canada pedestrian crossing sign Children crossing, Ireland Blind pedestrian crossing sign, Pennsylvania Special needs child crossing, New York City Blind child, Delaware Hearing impaired child sign Pennsylvania Deaf child area sign, New York State Deaf child, Delaware Deaf children near sign, California Caution ( running family ), California Autistic child warning, USA Schools The 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. Ontario uses a white on blue version of this sign. U.S. / Canada school zone Australia children sign Australia : School ahead New Zealand children sign Philippines children sign Botswana, Lesotho, Namibia, South Africa, Swaziland and Tanzania children sign Indonesia children sign Ireland children crossing sign Japan children crossing sign Malaysia children crossing sign UK children sign Netherlands children sign Brazil school zone sign Brazil children sign Norway children sign France children sign Thailand School crossing ahead Thailand School children crossing Russia children crossing sign Poland children crossing sign Poland : kindergarten U.S. school bus stop ahead sign Bicycle Australia bicycles sign Poland bicycle crossing warning sign Norway bicycle crossing warning sign Russia bicycle crossing warning sign U.K. bicycles crossing ahead sign U.S. bicycles ahead sign New York City share the road sign Pennsylvania share the road sign Maryland share the road sign San Francisco bike lane sign U.S. bikeway narrows sign Other signs with unprotected people Norway skiers crossing sign. Sweden skiers crossing sign. U.S. playground ahead sign. Canada playground ahead sign. Fire stations These signs warn of approach to where firefighters may be entering the road with fire engines or other emergency apparatus, where other drivers will have to stop and wait until they pass. U.S. fire station sign. Canadian fire station sign. Delaware emergency vehicles sign. Wisconsin fire trucks entering when signal flashes sign. Texas emergency vehicles sign. New York State firehouse sign. Maryland `` firehouse signal '' sign. Oncoming traffic The 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. Australia and New Zealand two - way traffic sign Brazil two - way traffic sign Ireland two - way traffic sign Italy, Latvia, and Sudan two - way traffic sign Jamaica two - way traffic sign Sweden two - way traffic sign Germany two - way traffic ahead sign Norway two - way traffic sign Poland two - way traffic sign U.S. two - way traffic sign Level crossing ( railway crossing ) These signs are used to warn of level crossings 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 barriers. Crossing with gate Brazil controlled railroad crossing sign UK level crossing with gate or barrier sign Ireland level crossing with gates sign Italy rail crossing with gates sign Sweden crossing with gate sign German level crossing sign used for guarded and unguarded crossings Norway crossing with gate sign Russia crossing with gate sign Unguarded crossing Australia railway level crossing without gate or barrier ahead sign Philippines uncontrolled railroad crossing sign Brazil uncontrolled railroad crossing sign UK railway level crossing without gate or barrier ahead Taiwan : crossing, no gate, first warning Italy rail crossing without safety arm Sweden unguarded crossing sign Norway unguarded crossing sign Russia unguarded crossing sign Other crossings Philippines railroad crossing with signals ahead sign Ireland automatic level crossing sign Finland tram crossing sign Greece tram crossing sign UK tramcars crossing ahead sign Russia tram crossing sign Norway tram crossing sign U.S. railroad crossing sign ( general ) Canada railroad crossing sign ( general ) Caltrans light rail crossing ahead sign U.S. humped - crossing low vehicle scrape risk U.S. skewed crossing ( hazard to cyclists ) Australia and New Zealand railroad crossing with signals ahead New Zealand cyclists watch for track - ruts Warning at crossing ( crossbucks ) Philippines railroad crossing sign U.S. railroad crossing sign Thai RR crossing sign Norway signal track level crossing sign Netherlands track level crossing sign Austrian railway crossing sign Russia single - track railway sign Taiwan : electric tram crossing, multiple tracks UK railway or tramway crossing without gate or barrier ( the crossbuck ) Falling rocks 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 `` fallen rock '', `` falling rock '', or `` rock slide ''. In Italy the words may be `` caduta sassi '' or `` caduta massi '' ; in France `` chûte de pierres '' ; in Mexico `` derrumbe s ''. Australia and New Zealand falling rocks sign Philippines road narrow sign United Kingdom and Hong Kong `` falling rocks '' warning sign Norway falling rocks sign Ukraine falling rocks sign Japanese `` falling rocks '' sign New York State fallen rock sign Pennsylvania falling rocks sign North Carolina falling rock sign Idaho watch for rock sign Caltrans rock slide area sign New York State rock / mud slides warning sign Caltrans `` falling rocks '' sign Canada `` falling rocks '' sign Other warnings ( aircraft - related ) For example, 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. Philippines low flying aircraft warning sign Norway low flying aircraft sign Russia low flying aircraft sign UK low flying aircraft sign Ireland low flying aircraft sign New York State low flying planes sign Delaware low flying aircraft Pennsylvania balloon launch area Low flying airplanes cross here sign, Wisconsin Crosswinds or side winds Flying socks, as indicated 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. Japan cross winds sign UK side winds likely ahead warning sign Sweden side winds warning sign Norway cross winds sign Poland side winds sign Ukraine powerful crosswinds area sign New York State crosswinds sign Pennsylvania high cross winds sign Idaho frequent high winds sign Road conditions `` Slippery when wet '', `` grooved pavement '' ( warning to motorcyclists and bicyclists ), `` Open joints on bridge '', `` Icy Road '', `` Bridge freezes before roadway '' and variants thereof, and `` bump '' or `` dip '' ahead ( not related to construction ). 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., 5 percent ). Steep hills may also feature `` Runaway truck escape '' or `` Emergency stop '' areas with corresponding signs. The UK has a sign warning of `` Adverse camber '' on a curve. Also `` Loose gravel '', `` Soft shoulder '', `` Speed hump '', and `` Watch for Ice. '' Slippery pavement Australia and New Zealand slippery when wet Philippines slippery when wet United States slippery when wet U.S. and Canada bridge ices before road Brazil slippery road sign Japan slippery when wet Swedish slippery pavement sign Norway slippery pavement sign UK slippery road ahead sign Poland slippery pavement sign Poland icy or snow - covered roads Czech black ice prone area Nebraska, may be icy ahead Michigan, bridge may be icy Steep grade Australia and New Zealand steep descent sign Philippines steep descent sign U.S. and Canada steep grade / hill sign U.S. steep hill sign U.S. and Canada steep grade / hill percentage sign California watch downhill speed Brazil steep descent sign Austria steep grade sign UK 10 % down grade sign Netherlands 10 % grade sign France 10 % down grade sign Norway steep grade sign Poland steep grade sign Korea steep descent sign Japan steep descent sign Delaware hill sign ( alternate ) Idaho steep grade percentage sign Bumpy road Australia and New Zealand hump sign Philippines hump sign U.S. bump sign New Jersey bumps sign U.S. rough road sign Brazil bump sign Brazil rough road sign Ireland bumpy road sign Japan bumpy road sign Korea bumpy road sign Norway bumpy road sign Germany bumpy road sign Ukraine bump sign Canada bump sign Canada bumps sign Miscellaneous Other U.S. and Australia : Dip New York State rumble strips ahead sign Idaho occasional blinding dust storms sign Road floods during high tide, Hawaii Frost heaves, Idaho Severe storm area, Idaho Ferry crossing, Missouri Fog area, Ohio Czech fog area Netherlands rain or snow area Italy risk of fire United Kingdom try your brakes Unusual warning signs UK : toad zone. UK, Tank Crossing. Lithuania : blind spot. Netherlands ( Texel ) : caution quicksand. New Zealand, Penguin Crossing. Colombia, opossum area. U.S. : remote controlled railway locomotives. Germany : watch out, the railway crossing is privately owned. No unpermitted crossing. Australia, Assorted Wildlife Crossing. Svalbard, Polar Bear Area ( new white bear variant ). U.S. ( vintage ), Avoid Bears. On Laos / Thailand border : ahead we drive on opposite side of road. Poland : danger, car ferry ahead. New Zealand : exceptional curves / intersections / R.R. x-ing situation. U.S. : trolley testing underway. U.S. ( Alaska ) : Warning : No Warnings Ahead. Taiwan, owl crossing. Danger High Voltage, Saudi Arabia. UK, Slow Children & Ducks Crossing sign. U.S. ( California ), Hang - Glider Xing ( crossing ). Germany : look out wide snowcat vehicles. Poland : buildings may collapse, steer clear. South Korea, Beware of White Squirrels. Thailand : go upland during tremors, tsunami zone. U.S. ( Alaska ) Bison may ram cars ( hand - painted ). South Africa : baboons. Austria : caution, marmots ! Namibia : leopard zone. Australia : fruit bats, virus risk. South Africa : lions, stay in car. UK : badger crossing. Germany : danger of drowning in channel. WWII urban front line : sightseers stay back. Germany : unexploded ordnance. Falkland Islands : slow, landmines. Germany : flash flood area. Italy : flash flood area ( hydroelectric activity ). Australia : frill - necked lizard zone. Finland : mosquito swarms. South Africa : beware of hippos. Greenland : musk ox area. Germany : mind the otters. Namibia : warthog zone. Germany : falling ice. Italy : beware of toxic gases from fumaroles. Greenland : dogsled crossing. Germany : danger of collapse due to mine subsidence. Germany : unstable underground. U.S. : underground fire -- road might collapse. Germany : pet and wildlife conflicts, disease - bearing ticks. On barb wire at Auschwitz 1 : high voltage. Germany : overhanging vegetation. Ireland : quayside dropoff. Australia, Tasmanian devil area. Japan : Iriomote cat zone. Australia : golf ball zone. Réunion Island : risk of falling palm fronds. Trolle Ljungby, Sweden : pheasant family crossing. Israel : camel zone sign, multilingual. Norway : military exercise underway. Bulgaria : children ( `` children do n't have brakes '' ). Scotland : passing zone ( plus hand - painted caution lambs sign on old tire ). Bosnia : ( 1992 - 95 wartime ) hand - painted Alert Snipers ! U.S. ( Alaska ) : deadly cold, proceed only at your own risk. U.S. ( California ) : message to undocumented immigrants that crossing the desert can be fatal. Danger of death, a safari park of Italy. U.S. ( Oregon ) : Deadly wave warning. Czech, Alert : traffic accidents with serious consequences. Vandal - modified joke signs Germany : generic caution with added Santa sleigh. Sweden : generic caution symbol with added skvader jackalope. In Finland. a generic caution with vandal - added hedgehog picture. Vandal added skis to an Austrian Cattle Crossing sign. Germany : stork area with added droppings. In France, a vandal added animals. Generic Warning symbol to which a Czech vandal added : `` beware of low - flying witches ''. Australian Cassowary Crossing and Speed Bump signs modified by vandal to be a combined before and after roadkill scene. Pedestrian Crossing with added wings and Red Bull can. In Scotland, Cattle Crossing sign vandal - modified to warn against elephants. Germany : waiter added to caution sign. Germany : Kitesurfer added to bumpy road sign. Warning signs with lights Some warning signs have flashing lights to alert drivers of conditions ahead or remind drivers to slow down. In Britain, they are called warning light. Flashing lights can be dangerous for people with certain forms of epilepsy and / or sensory processing disorder. Attached lights School zone traffic warning sign in Denmark. France red traffic signal ahead. Crosswalk alert with solar - powered lit outline. Denmark portable multipurpose traffic warning array. School Zone sign with warning light in U.S. U.S. flood zone sign. Non-traffic warning signs Sign in Niagara Falls, Ontario, warning people not to climb over guard rail overlooking the Niagara River. Warning entrance sign to an exhibitions at Palazzo Pitti museum compound, Florence, Italy. Warning signs are also found on other potential dangerous sites. At the base of electricity pylons or fences of substations or radiotechnical equipment with open parts leading high voltage, there are signs warning of high voltage. Warning signs can be found at the top of inclines. `` Beware of Dog '' is a typical warning of the presence of a dog, but there is no standard sign design. Others include wet floor signs. See also Hazard symbol Note Wikimedia Commons has media related to Warning signs. ^ Federal Highway Administration. `` Section 1A. 13 Definitions of Words and Phrases in This Manual ''. Manual on Uniform Traffic Control Devices ( 2003 ed. ). Washington, DC. p. 1A - 14. Retrieved 2009 - 03 - 01. Warning Sign -- a sign that gives notice to road users of a situation that might not be readily apparent. ^ `` CNN - Defendants get 15 - year prison sentences for stop - sign killings - June 20, 1997 ''. cnn.com. ^ `` Florida Defendants Get Retrial on Manslaughter Convictions Resulting from Deaths at Intersection Where Stop Sign Downed ; Dissenting Judge Argues for Acquittal ''. usroads.com. ^ `` Tampabay : Suddenly, stop sign case is over ''. sptimes.com. ^ `` Highway safety sign becomes running story on immigration - The San Diego Union - Tribune ''. signonsandiego.com. ^ Driver 's Handbook Traffic signs Signs Warning sign Regulatory sign Prohibitory traffic sign Mandatory sign Special regulation sign Stop sign Yield sign Crossbuck Dead End sign One - way traffic Speed limit ( by country ) Advisory speed limit Information sign Direction, position, or indication sign Variable - message sign Bilingual sign Driver location signs Logo sign Priority to the right By comparison Comparison of European road signs Comparison of MUTCD - influenced traffic signs Comparison of traffic signs in English - speaking countries By country Africa Botswana Mauritius South Africa Zimbabwe Asia Azerbaijan Bangladesh Brunei Cambodia China Hong Kong India Indonesia Iran Israel Japan Laos Malaysia Nepal Pakistan Singapore South Korea Sri Lanka Thailand Turkey United Arab Emirates Vietnam Europe Austria Bosnia and Herzegovina Czech Republic Denmark Estonia Finland France Germany Greece Iceland Ireland Italy Liechtenstein Netherlands Norway Poland Sweden Switzerland Ukraine United Kingdom Scotland Wales North America Canada Mexico United States Oceania Australia New Zealand South America Argentina Brazil Chile Colombia Lights Traffic light Traffic - light signalling and operation Traffic light control and coordination Typefaces Alfabeto Normale ( IT ) Austria ( AT ) Caractères ( FR ) Clarendon ( US ) Clearview ( US / CA / ID / PH / LK ) DIN 1451 ( DE / SADC ) Drogowskaz ( PL ) Enigmatic ( JP / KR ) Highway Gothic ( Global ) Bitstream Vera Sans ( TW ) Frutiger ( Europe ) GOST 10807 - 78 ( USSR ) GOST R 52290 - 2004 ( RU ) Hangil ( KR ) LLM Lettering ( MY ) Motorway ( Europe ) NPS Rawlinson Roadway ( US ) Panno ( KR ) SNV ( CH ) Tern ( Europe ) Trafikkalfabetet ( NO ) Transport ( UK ) Tratex ( SE ) Vialog ( JP ) Conventions Geneva Convention on Road Traffic Vienna Convention on Road Traffic Vienna Convention on Road Signs and Signals Manual on Uniform Traffic Control Devices ( US ) SADC Road Traffic Signs Manual ( SADC ) Traffic Signs Regulations and General Directions ( UK ) Retrieved from `` https://en.wikipedia.org/w/index.php?title=Warning_sign&oldid=816480553 '' Categories : Traffic signs Safety Hazards Warning systems Hidden categories : Wikipedia articles needing reorganization from December 2017 Articles needing cleanup from December 2017 All pages needing cleanup Articles that may contain original research from December 2017 All articles that may contain original research Articles needing additional references from December 2017 All articles needing additional references Articles lacking reliable references from December 2017 All articles lacking reliable references Articles with multiple maintenance issues Articles that may be too long from December 2008 Articles containing Italian - language text Articles containing French - language text Talk Contents About Wikipedia Башҡортса Deutsch Español فارسی Français 한국어 Հայերեն Italiano Қазақша Lëtzebuergesch Lietuvių Norsk Norsk nynorsk Polski Română Русский Svenska தமிழ் 中文 Edit links This page was last edited on 21 December 2017, at 16 : 43. 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Question: the sign marked in this triangle in red colour
Answer: to warn of level crossings ahead