Speed Limit Signs & Low Bridges

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Slide 0: Safety on the Move : A Guide to UK Height and Speed Signs Preventing " Bridge Bashing " Hundreds of incidents occur annually ; all bridges under 16 ' 6 " ( Sm ) are normally signed to prevent accidents . Regulatory Sign ( Mandatory Height Limit ) Warning Sign ( Maximum Safe Headroom ) Speed Limit Regulations Default Urban Limits : 30 mph ( England / Scotland ) , 20 mph ( Wales ) in street - lit areas unless signed . Enforcement & Specialized Signage Camera Enforcement Zones The National Speed Limit : Applies for the road type and vehicle class . Average Speed Zones : Speed measured between two points . HIGH - VEHICLE AHEAD FURN OAER High - Vehicle Detection Systems : Infra - red beams activate flashing amber lights for overheight drivers . Arch Bridge Navigation : White chord markings show variable headroom , high vehicles use center . Enhanced Visibility Features : Black and yellow bands prevent collisions . Mandatory Speeds ( Legal Maximum ) Advisory Speeds ( Recommended at hazards ) Minimum Speed Limits : Must be followed unless unsate / impracticable . Repeater Signs : Reminders , used on unilt 30 mph roads . Variable Speed Limits : Temporary changes , often camera - enforced , and with National Speed Limit sign . Advance Warning & Diversions : Signage frequently includes arrows or maps to direct drivers . Slide 1: 50 Mastering UK Traffic Signs A visual guide to speed limits and clearance heights 70 VARIABLE SPEED LIMIT Slide 2: The Shape of Compliance Regulatory & Mandatory You must comply . Red rings dictate absolute limits and unlawful actions . Warning Hazards ahead . Red triangles provide critical awareness of physical constraints . Positive Instruction Mandatory actions or permissions , such as minimum permitted speeds . Slide 3: Baseline Speed Fundamentals In areas of street lighting ( excluding motorways ) , a 30 mph speed limit applies by default unless signed otherwise . Did You Know ? In Wales , this default limit is strictly 20 mph . Applies the maximum legal speed based on the specific type of road and the class of traffic you are driving . Slide 4: Entering and Exiting Speed Zones Town Boundaries Traffic Calming Zones Motorway Regulations Anytown Larger signs indicate the immediate start of a limit upon entering a settlement . ZONE Entrance to a 20 mph zone indicates you will likely encounter physical traffic - calming measures . A specific sign marks the end of this zone and the return to a 30 mph limit . Start of motorway regulations automatically invokes the national speed limit unless a different limit is explicitly signed . Slide 5: The Logic of Repeater Signs Repeater signs for 30 mph limits are used ONLY on roads with no street lighting . Repeater signs for the national speed limit are used ONLY on roads with street lighting ( excluding motorways ) . Road markings are frequently used in conjunction with these upright signs to reinforce the active limit . Slide 6: Dynamic and Temporary Speeds Variable Speed Limits Deployed on lengths of road where enforcement cameras are active . An End sign signals the return to the national speed limit . Road Works Marks the conclusion of temporary speed limits through work zones , supplementing the permanent limit beyond . Extended 30 mph Zones Placed on lit roads to alert drivers that a previous , higher limit has been replaced by removing the old speed signs . Slide 7: Spotting Enforcement Zones Average speed check Standard Camera Sign : Indicates an area where speed cameras are in use . Often supplemented by the current speed limit roundel as a reminder . Average Speed Sign : Measures vehicle speed continuously between two distinct camera points over a length of road . Environment Context Lit Road : A camera warning on a lit road implies a 30 mph limit is in effect ( no repeaters will be present ) . Unlit Road : A camera warning on an unlit road implies the national speed limit is in effect ( no repeaters will be present ) . Slide 8: Advisories and Minimums Max speed 30 Advisory Speeds Recommends the maximum safe speed for a specific hazard . It is an advisory , not a statutory limit . Minimum Speeds Dictates the minimum permitted speed . You must travel at or above this speed unless it is impracticable or unsafe to comply . A distinct sign with a red diagonal line marks the end of this requirement . Slide 9: The Dangers of Bridge Bashing - Hundreds of incidents occur annually where vehicles strike overhead bridges . - These strikes are catastrophic , resulting in fatalities for both road and rail users . 16 feet 6 inches ( approx . 5 metres ) All bridges with a clearance lower than this height are normally signed . Ensure you know your vehicle's exact height . Slide 10: Mandatory Height Restrictions Non - Arch Bridges : Mandatory signs are used exclusively here . They are placed both directly on the bridge and at the roadside approaching it . Dual Units : Signs show both metric and metric and imperial measurements . Older imperial - only signs are actively being phased out . Unlawful to Pass : It is a strict legal offense for an over - height vehicle to pass this sign . Advance Routing : Look for advance warning versions featuring arrows or alternative route diagrams to divert before getting stuck . Slide 11: Advance Warnings and Obstructions Advance Warning : Red triangle indicates maximum safe headroom , sited well before the obstruction . Distance Plates : Indicates the distance to the bridge , allowing time to safely stop or divert . Directional Arrows : Indicates the low bridge is located on a specific side road at a junction ahead . Structure Structural Variations : Indicates the reduced headroom is caused by an overhanging building or structure rather than a traditional bridge . Slide 12: Navigating Arch Bridges Chord Markings Scenario Action Plan - The Goal : Road markings intentionally guide high vehicles through the absolute highest part of the arch . -Yielding Rule : Drivers of ALL vehicles must give way to oncoming high vehicles in the middle of the road when there is insufficient room to pass . - Low Vehicle Exception : Cars and low vehicles may keep to the left - hand side , safely crossing the road markings , to allow oncoming high vehicles to pass . Slide 13: Infrastructure and Active Warnings OVERHEIGHT VEHICLE DIVERT Physical Conspicuity Black and yellow bands are frequently painted directly onto the arches , beams , and abutments to make the structure hyper - conspicuous against the environment . Active Infrared Warnings High - risk bridges utilize infra - red beams . If a high vehicle breaks the beam , it triggers the sign . Four amber lights will flash - the top pair alternating with the bottom pair - commanding the driver to stop immediately . Slide 14: The Environment Checklist Speed Compliance Default Assumption : 30 mph in lit areas ( 20 mph in Wales ) unless signed . Clearance Awareness The Threshold : Watch for signs if your vehicle is over 16ft 6in ( 5m ) . Repeater Check : Lit road = National limit repeaters . Unlit road = 30 mph repeaters . Shape Check : Blue circles mean minimum speed ; red rings mean maximum speed . Sign Check : Red rings mean unlawful to pass ; red triangles mean caution / advance warning . Arch Protocol : Always yield to high vehicles occupying the center of an arch bridge .
Speed Limit Signs & Low Bridges lesson slide 1
Slide 1: Safety on the Move : A Guide to UK Height and Speed Signs Preventing " Bridge Bashing " Hundreds of incidents occur annually ; all bridges under 16 ' 6 " ( Sm ) are normally signed to prevent accidents . Regulatory Sign ( Mandatory Height Limit ) Warning Sign ( Maximum Safe Headroom ) Speed Limit Regulations Default Urban Limits : 30 mph ( England / Scotland ) , 20 mph ( Wales ) in street - lit areas unless signed . Enforcement & Specialized Signage Camera Enforcement Zones The National Speed Limit : Applies for the road type and vehicle class . Average Speed Zones : Speed measured between two points . HIGH - VEHICLE AHEAD FURN OAER High - Vehicle Detection Systems : Infra - red beams activate flashing amber lights for overheight drivers . Arch Bridge Navigation : White chord markings show variable headroom , high vehicles use center . Enhanced Visibility Features : Black and yellow bands prevent collisions . Mandatory Speeds ( Legal Maximum ) Advisory Speeds ( Recommended at hazards ) Minimum Speed Limits : Must be followed unless unsate / impracticable . Repeater Signs : Reminders , used on unilt 30 mph roads . Variable Speed Limits : Temporary changes , often camera - enforced , and with National Speed Limit sign . Advance Warning & Diversions : Signage frequently includes arrows or maps to direct drivers .
Speed Limit Signs & Low Bridges lesson slide 2
Slide 2: 50 Mastering UK Traffic Signs A visual guide to speed limits and clearance heights 70 VARIABLE SPEED LIMIT
Speed Limit Signs & Low Bridges lesson slide 3
Slide 3: The Shape of Compliance Regulatory & Mandatory You must comply . Red rings dictate absolute limits and unlawful actions . Warning Hazards ahead . Red triangles provide critical awareness of physical constraints . Positive Instruction Mandatory actions or permissions , such as minimum permitted speeds .
Speed Limit Signs & Low Bridges lesson slide 4
Slide 4: Baseline Speed Fundamentals In areas of street lighting ( excluding motorways ) , a 30 mph speed limit applies by default unless signed otherwise . Did You Know ? In Wales , this default limit is strictly 20 mph . Applies the maximum legal speed based on the specific type of road and the class of traffic you are driving .
Speed Limit Signs & Low Bridges lesson slide 5
Slide 5: Entering and Exiting Speed Zones Town Boundaries Traffic Calming Zones Motorway Regulations Anytown Larger signs indicate the immediate start of a limit upon entering a settlement . ZONE Entrance to a 20 mph zone indicates you will likely encounter physical traffic - calming measures . A specific sign marks the end of this zone and the return to a 30 mph limit . Start of motorway regulations automatically invokes the national speed limit unless a different limit is explicitly signed .
Speed Limit Signs & Low Bridges lesson slide 6
Slide 6: The Logic of Repeater Signs Repeater signs for 30 mph limits are used ONLY on roads with no street lighting . Repeater signs for the national speed limit are used ONLY on roads with street lighting ( excluding motorways ) . Road markings are frequently used in conjunction with these upright signs to reinforce the active limit .
Speed Limit Signs & Low Bridges lesson slide 7
Slide 7: Dynamic and Temporary Speeds Variable Speed Limits Deployed on lengths of road where enforcement cameras are active . An End sign signals the return to the national speed limit . Road Works Marks the conclusion of temporary speed limits through work zones , supplementing the permanent limit beyond . Extended 30 mph Zones Placed on lit roads to alert drivers that a previous , higher limit has been replaced by removing the old speed signs .
Speed Limit Signs & Low Bridges lesson slide 8
Slide 8: Spotting Enforcement Zones Average speed check Standard Camera Sign : Indicates an area where speed cameras are in use . Often supplemented by the current speed limit roundel as a reminder . Average Speed Sign : Measures vehicle speed continuously between two distinct camera points over a length of road . Environment Context Lit Road : A camera warning on a lit road implies a 30 mph limit is in effect ( no repeaters will be present ) . Unlit Road : A camera warning on an unlit road implies the national speed limit is in effect ( no repeaters will be present ) .
Speed Limit Signs & Low Bridges lesson slide 9
Slide 9: Advisories and Minimums Max speed 30 Advisory Speeds Recommends the maximum safe speed for a specific hazard . It is an advisory , not a statutory limit . Minimum Speeds Dictates the minimum permitted speed . You must travel at or above this speed unless it is impracticable or unsafe to comply . A distinct sign with a red diagonal line marks the end of this requirement .
Speed Limit Signs & Low Bridges lesson slide 10
Slide 10: The Dangers of Bridge Bashing - Hundreds of incidents occur annually where vehicles strike overhead bridges . - These strikes are catastrophic , resulting in fatalities for both road and rail users . 16 feet 6 inches ( approx . 5 metres ) All bridges with a clearance lower than this height are normally signed . Ensure you know your vehicle's exact height .
Speed Limit Signs & Low Bridges lesson slide 11
Slide 11: Mandatory Height Restrictions Non - Arch Bridges : Mandatory signs are used exclusively here . They are placed both directly on the bridge and at the roadside approaching it . Dual Units : Signs show both metric and metric and imperial measurements . Older imperial - only signs are actively being phased out . Unlawful to Pass : It is a strict legal offense for an over - height vehicle to pass this sign . Advance Routing : Look for advance warning versions featuring arrows or alternative route diagrams to divert before getting stuck .
Speed Limit Signs & Low Bridges lesson slide 12
Slide 12: Advance Warnings and Obstructions Advance Warning : Red triangle indicates maximum safe headroom , sited well before the obstruction . Distance Plates : Indicates the distance to the bridge , allowing time to safely stop or divert . Directional Arrows : Indicates the low bridge is located on a specific side road at a junction ahead . Structure Structural Variations : Indicates the reduced headroom is caused by an overhanging building or structure rather than a traditional bridge .
Speed Limit Signs & Low Bridges lesson slide 13
Slide 13: Navigating Arch Bridges Chord Markings Scenario Action Plan - The Goal : Road markings intentionally guide high vehicles through the absolute highest part of the arch . -Yielding Rule : Drivers of ALL vehicles must give way to oncoming high vehicles in the middle of the road when there is insufficient room to pass . - Low Vehicle Exception : Cars and low vehicles may keep to the left - hand side , safely crossing the road markings , to allow oncoming high vehicles to pass .
Speed Limit Signs & Low Bridges lesson slide 14
Slide 14: Infrastructure and Active Warnings OVERHEIGHT VEHICLE DIVERT Physical Conspicuity Black and yellow bands are frequently painted directly onto the arches , beams , and abutments to make the structure hyper - conspicuous against the environment . Active Infrared Warnings High - risk bridges utilize infra - red beams . If a high vehicle breaks the beam , it triggers the sign . Four amber lights will flash - the top pair alternating with the bottom pair - commanding the driver to stop immediately .
Speed Limit Signs & Low Bridges lesson slide 15
Slide 15: The Environment Checklist Speed Compliance Default Assumption : 30 mph in lit areas ( 20 mph in Wales ) unless signed . Clearance Awareness The Threshold : Watch for signs if your vehicle is over 16ft 6in ( 5m ) . Repeater Check : Lit road = National limit repeaters . Unlit road = 30 mph repeaters . Shape Check : Blue circles mean minimum speed ; red rings mean maximum speed . Sign Check : Red rings mean unlawful to pass ; red triangles mean caution / advance warning . Arch Protocol : Always yield to high vehicles occupying the center of an arch bridge .
📖 DVSA Revision Lesson ⏱️ 10 Min Read ❓ 10 Practice Questions 🌐 68 Languages Support

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📜 Official Lesson Transcript & Audio SRT Dialogue 112 Timestamps
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00:00 Okay, so whether you're brand new behind the wheel or you've been driving for years, let's
00:04 be honest, UK road signs can sometimes feel like a whole other language.
00:09 So in this explainer, we're going to decode the essentials so you can drive with way
00:12 more confidence knowing exactly what the road is trying to tell you.
00:16 Make sure that you are not a bridge basher.
00:18 I mean, wow, that's a direct quote from the UK government.
00:21 It's pretty blunt, right?
00:22 It just immediately sets the tone and reminds us that this isn't just about theory.
00:26 Having these signs wrong can have some really serious, real world consequences.
00:31 So here's what we've got lined up.
00:33 We'll kick things off with that bridge basher idea.
00:36 Then we'll get into the language of speed and tackle the tricky subject of low bridges.
00:40 After that, I've got a fantastic little code breaker for you that makes everything else
00:44 make sense.
00:45 And we'll wrap it all up with a final check to make sure it all sticks.
00:49 Alright, part one.
00:51 Don't be a bridge basher.
00:52 It sounds almost like a slogan, but the reality behind that phrase is no joke.
00:57 Let's dig into what actually happens when drivers miss these crucial signs.
01:01 You know, the scale of this is pretty shocking.
01:03 We're talking hundreds of times a year, and these aren't just little scrapes.
01:06 A bridge strike can be catastrophic, even fatal, not just for the driver, but for people on
01:11 trains if it's a railway bridge, and here's the kicker.
01:14 It all comes down to vehicles being too high, and it's almost always preventable.
01:19 It's all about reading the signs.
01:21 Okay, let's switch gears and talk about speed.
01:24 We all see speed limit signs every day, but there's actually a bit more to it than just a number
01:29 in a circle.
01:30 It's a whole language in itself.
01:32 So, for most of the UK, if you're in a built-up area and you see streetlights, the default
01:37 speed limit is 30 miles per hour.
01:39 That's your baseline.
01:41 But, and this is a big butt.
01:43 You've got to remember that in Wales, that default is now 20 miles per hour, so always be
01:47 aware of where you are.
01:48 Ah, this one.
01:50 This is the sign that trips so many people up, the white circle with the black stripe.
01:55 It does not mean there's no speed limit.
01:58 All it means is that the national speed limit applies, and that speed is different depending
02:02 on your vehicle and the type of road.
02:05 For a car, it's usually 60 on a single carriageway and 70 on a dual carriageway or motorway.
02:10 And hey, it's easy to forget the speed limit, especially on a long-boring road.
02:15 That's why you'll see these smaller, repeater signs.
02:17 They're just little nudges, you know?
02:19 A friendly reminder of the limit for that stretch of road, so it stays fresh in your mind.
02:23 Okay, let's bring our attention back up from the speedometer to the top of our vehicles.
02:28 We're talking about the challenge of low bridges.
02:31 This takes us right back to that whole bridge-bashier thing we started with, and the signs that
02:34 are absolutely critical to avoiding disaster.
02:37 So, here is the magic number you need to know, 16 feet, 6 inches.
02:42 That's about 5 meters.
02:44 Any bridge with less clearance than this is supposed to have a sign.
02:47 That's the official point where they have to warn you about the low headroom.
02:51 But what happens when a bridge isn't just a flat slab, you know, like those old arched
02:56 bridges?
02:57 The height is different depending on where you are in the lane.
03:00 It's highest in the middle and gets lower at the edges.
03:03 So how do you navigate that?
03:06 The solution is actually pretty clever.
03:08 They use something called cord markings.
03:10 You can see them here.
03:11 These lines on the road that literally map out the different height zones under the arch.
03:15 It's like a visual guide telling you exactly where the tall vehicles can safely fit.
03:20 And this system creates a very clear set of rules for everyone.
03:24 If you're in a high vehicle, you've got to stick to the center.
03:27 And this is so important.
03:28 Oncoming traffic is supposed to see you doing this and give way.
03:32 If you're in a smaller car, you can stick to the left.
03:34 But only if it's safe and there's enough room for everybody.
03:37 It's all about cooperation.
03:39 Okay, this is my favorite part.
03:42 We've talked about specific signs for speed and height, but what if I told you there was
03:46 a simple secret, a code breaker that unlocks the meaning of pretty much every road sign?
03:51 Well there is.
03:52 And it's incredibly simple.
03:54 And here it is.
03:55 That's it.
03:56 It's all about the shape.
03:57 A circle gives an order.
03:59 A triangle gives a warning.
04:01 Seriously, if you just burn this one single fact into your brain, you'll instantly know what
04:06 the road is telling you, an order versus a warning.
04:09 So let's break that down.
04:11 When you see a circle or a roundell as it's officially called, you're being given a command.
04:15 It is not a helpful tip.
04:17 It is an order and it's illegal to disobey it.
04:20 Think about it.
04:21 The speed limit sign is a circle.
04:22 The height restriction sign is a circle.
04:24 They are both giving you direct orders.
04:26 Now, on the other hand, you have the triangle.
04:30 A triangle is your friend giving you a heads up.
04:32 It's a warning.
04:33 It's telling you, hey, pay attention.
04:35 There's a potential hazard coming up.
04:37 Maybe it's a low bridge, a sharp turn, or a slippery road.
04:41 It's not an order, but it's crucial information that you need to heed to stay safe.
04:45 Okay, let's wrap this all up with our final check.
04:49 Because once you have this knowledge, you're not just someone following rules anymore.
04:52 You become an interpreter of the road.
04:55 You can see what's coming and react with so much more confidence.
04:59 So if you take away just one single thing today, please let it be this.
05:03 A circle is an order you absolutely must obey.
05:06 A triangle is a warning you absolutely must pay attention to.
05:10 That simple difference is the very foundation of safe driving in the UK.
05:14 So I've got a little challenge for you.
05:15 Next time you're out driving, or even just as a passenger, start playing this game.
05:19 Look at the signs and just identify the shape.
05:22 Is it an order?
05:23 Or is it a warning?
05:24 You'll be amazed at how quickly you start decoding the road and how much it's really telling
05:27 you.

📖 Speed Limit Signs & Low Bridges

📌 1. Speed Limit Signs

In areas of street lighting (other than on motorways), a speed limit of 30 mph applies unless signs show otherwise. In Wales, this limit is 20 mph.

  • •
    Maximum speed: The maximum speed, in miles per hour, at which traffic may travel, if it is safe to do so.
  • •
    National speed limit: A white circular sign with a black diagonal stripe means the national speed limit for the type of road and class of traffic applies.
  • •
    Repeater signs: A larger sign indicates the start of a speed limit. Smaller repeater signs act as reminders. Repeater signs for a 30 mph limit are used only on roads with no street lighting. Repeater signs for the national speed limit are used only on roads with street lighting (other than motorways).
  • •
    Road markings: Road markings can be used in conjunction with upright signs to indicate the speed limit.
  • •
    20 mph zones: Signs indicate the entrance to a 20 mph zone in which traffic-calming measures may be encountered. Another sign indicates the end of a 20 mph zone and start of a 30 mph speed limit.
  • •
    Town/Village boundaries: Start of a speed limit at the boundary of a town or village.
  • •
    Motorways: A special symbol indicates the start of motorway regulations, including the national speed limit (unless a different speed limit is signed).
  • •
    Temporary extensions: A temporary sign may point out a road with street lighting where an existing 30 mph limit originally ended but has subsequently been extended. This sign alerts drivers that a previous higher limit has been replaced by a 30 mph limit by the removal of speed limit signs.
  • •
    Road works: Signs indicate the end of road works and any temporary speed limit through those works (may be supplemented by a sign indicating the permanent speed limit beyond the road works).
The maximum speed, in miles per hour, at which traffic may travel, if it is safe to do so.
🖼️ The maximum speed, in miles per hour, at which traffic may travel, if it is safe to do so.
The national speed limit for the type of road and class of traffic applies.
🖼️ The national speed limit for the type of road and class of traffic applies.
Road marking used in conjunction with upright signs to indicate the speed limit.
🖼️ Road marking used in conjunction with upright signs to indicate the speed limit.
Entrance to a 20 mph zone in which traffic-calming measures may be encountered.
🖼️ Entrance to a 20 mph zone in which traffic-calming measures may be encountered.
End of 20 mph zone and start of 30 mph speed limit.
🖼️ End of 20 mph zone and start of 30 mph speed limit.
Start of a speed limit at the boundary of a town or village.
🖼️ Start of a speed limit at the boundary of a town or village.
Start of motorway regulations, including the national speed limit (unless a different speed limit is signed).
🖼️ Start of motorway regulations, including the national speed limit (unless a different speed limit is signed).
Point on a road with street lighting where an existing 30 mph limit originally ended but has subsequently been extended (temporary sign). This sign alerts drivers that a previous higher limit has been replaced by a 30 mph limit by the removal of speed limit signs.
🖼️ Point on a road with street lighting where an existing 30 mph limit originally ended but has subsequently been extended (temporary sign). This sign alerts drivers that a previous higher limit has been replaced by a 30 mph limit by the removal of speed limit signs.
End of road works and any temporary speed limit through those works (may be supplemented by a sign indicating the permanent speed limit beyond the road works).
🖼️ End of road works and any temporary speed limit through those works (may be supplemented by a sign indicating the permanent speed limit beyond the road works).

📌 2. Enforcement Cameras and Advisory Speeds

  • •
    Speed cameras: Signs warn of an area where speed cameras are in use. Other signs indicate a length of road where two cameras are used to measure the average speed of a vehicle between two points. Reminders that enforcement cameras are in use may be supplemented by a speed limit sign.
  • •
    Cameras on specific roads: Specific signs indicate a speed camera nearby on a lit road with a 30 mph speed limit (i.e. where there are no speed limit repeater signs) or on an unlit road subject to the national speed limit.
  • •
    Variable limits: Signs indicate the start of a variable speed limit on a length of road where enforcement cameras are in use. Another sign indicates the end of a variable speed limit, meaning the national speed limit for the type of road and class of traffic now applies.
  • •
    Advisory speed: A rectangular plate may show the maximum speed advised, in miles per hour, at a bend (the plate may be used with other warning signs).
  • •
    Minimum speed: A blue circular sign indicates a minimum speed permitted, in miles per hour, unless it is impracticable or unsafe to comply. A similar sign with a red diagonal line marks the end of the minimum speed requirement.
Area where speed cameras are in use.
🖼️ Area where speed cameras are in use.
Length of road where 2 cameras are used to measure the average speed of a vehicle between 2 points.
🖼️ Length of road where 2 cameras are used to measure the average speed of a vehicle between 2 points.
Reminder that enforcement cameras are in use (may be supplemented by a speed limit sign).
🖼️ Reminder that enforcement cameras are in use (may be supplemented by a speed limit sign).
Speed camera nearby on a lit road with a 30 mph speed limit (i.e. where there are no speed limit repeater signs).
🖼️ Speed camera nearby on a lit road with a 30 mph speed limit (i.e. where there are no speed limit repeater signs.
Speed camera nearby on an unlit road subject to the national speed limit (i.e. where there are no speed limit repeater signs).
🖼️ Speed camera nearby on an unlit road subject to the national speed limit (i.e. where there are no speed limit repeater signs.
Start of variable speed limit on a length of road where enforcement cameras are in use.
🖼️ Start of variable speed limit on a length of road where enforcement cameras are in use.
End of variable speed limit. The national speed limit for the type of road and class of traffic now applies.
🖼️ End of variable speed limit. The national speed limit for the type of road and class of traffic now applies.
Maximum speed advised, in miles per hour, at a bend (the plate may be used with other warning signs).
🖼️ Maximum speed advised, in miles per hour, at a bend (the plate may be used with other warning signs.
Minimum speed permitted, in miles per hour, unless it is impracticable or unsafe to comply.
🖼️ Minimum speed permitted, in miles per hour, unless it is impracticable or unsafe to comply.
End of minimum speed requirement.
🖼️ End of minimum speed requirement.

📌 3. Low Bridge Signs: Overview

Each year there are hundreds of incidents in which bridges are struck by vehicles too high to pass under them. Both rail and road users have been killed in these incidents. Look out for signs in this section and make sure that you are not a bridge basher.

  • •
    All bridges with a clearance of less than 16 feet 6 inches (about 5 metres) are normally signed. Both regulatory roundels and warning triangles can be used, depending on the type of bridge.
  • •
    Bridges particularly at risk from strikes may have a variable message sign that is activated by high vehicles passing through an infra-red beam. When the sign is activated, four amber lights flash, the top pair alternating with the bottom pair.
bridge-strike
🖼️ bridge-strike
overheight-vehicle-divert
🖼️ overheight-vehicle-divert

📌 4. Low Bridge: Regulatory and Warning Signs

  • •
    Regulatory signs (Mandatory): At non-arch bridges mandatory signs may be used; it is unlawful for an overheight vehicle to pass one of these. They are placed on the bridge and at the side of the road in front of the bridge. No vehicles over the height shown may pass the sign (height shown in metric and imperial units). Some height restrictions may still show imperial units of measurement only; these signs will be replaced when they reach the end of their life.
  • •
    Advance warning of a mandatory height restriction ahead may include an arrow, if the restriction is on a side road. Signs can also show the location of a mandatory height restriction ahead, with indication of an alternative route.
  • •
    Warning signs (Triangles): A warning sign indicates the maximum headroom under a bridge or other overhead obstruction, in metric and imperial units. This sign may be sited well in advance of a bridge, with the distance (in either yards or miles) shown on a plate; this may have an arrow to indicate that the bridge is on a side road at a junction ahead. Older signs not displaying metric and imperial units in one panel will be replaced when they reach the end of their life.
No vehicles over the height shown may pass the sign (height shown in metric and imperial units).
🖼️ No vehicles over the height shown may pass the sign (height shown in metric and imperial units).
Advance warning of a mandatory height restriction ahead; the sign may include an arrow, if the restriction is on a side road.
🖼️ Advance warning of a mandatory height restriction ahead; the sign may include an arrow, if the restriction is on a side road.
Location of mandatory height restriction ahead, with indication of an alternative route.
🖼️ Location of mandatory height restriction ahead, with indication of an alternative route.
Older signs not displaying metric and imperial units in one panel will be replaced when they reach the end of their life.
🖼️ Older signs not displaying metric and imperial units in one panel will be replaced when they reach the end of their life.
Location of a low bridge ahead, with indication of an alternative route.
🖼️ Location of a low bridge ahead, with indication of an alternative route.
overhanging-building
🖼️ overhanging-building
Roundels or warning triangles will sometimes be incorporated into directional signs that may also indicate an alternative route to take to avoid the low bridge.
🖼️ Roundels or warning triangles will sometimes be incorporated into directional signs that may also indicate an alternative route to take to avoid the low bridge.
  • •
    Directional signs with roundels:
height-restriction
🖼️ height-restriction
height-restriction-roundel
🖼️ height-restriction-roundel
height-restriction-roundel-arrow
🖼️ height-restriction-roundel-arrow

📌 5. Arch Bridges and Temporary Restrictions

  • •
    Chord markings: Chord markings used indicate the points between which different headrooms over different parts of an arch bridge are available.
  • •
    Navigating arch bridges: The maximum safe headroom at an arch bridge is shown on the triangular warning signs. Road markings guide high vehicles through the highest part of the arch. Drivers of all vehicles should give way to oncoming high vehicles in the middle of the road when there is insufficient room to pass. Drivers of cars and other low vehicles may keep to the left-hand side of the road, crossing the road markings, where this would enable them to pass oncoming vehicles in safety.
  • •
    Temporary restrictions: Roundels may also be incorporated into road works signs to indicate temporary height restrictions. Other temporary signs indicate a temporary or permanent reduction in bridge headroom ahead.
The maximum safe headroom at an arch bridge is shown on the triangular warning signs. Road markings guide high vehicles through the highest part of the arch. Drivers of all vehicles should give way to oncoming high vehicles in the middle of the road when there is insufficient room to pass. Drivers of cars and other low vehicles may keep to the left-hand side of the road, crossing the road markings, where this would enable them to pass oncoming vehicles in safety.
🖼️ The maximum safe headroom at an arch bridge is shown on the triangular warning signs. Road markings guide high vehicles through the highest part of the arch. Drivers of all vehicles should give way to oncoming high vehicles in the middle of the road when there is insufficient room to pass. Drivers of cars and other low vehicles may keep to the left-hand side of the road, crossing the road markings, where this would enable them to pass oncoming vehicles in safety.
To make a bridge more conspicuous, black and yellow bands may be added to the arches or beams and to the abutments.
🖼️ To make a bridge more conspicuous, black and yellow bands may be added to the arches or beams and to the abutments.
Where reduced headroom over a road is due to an overhanging building or structure, a plate may be added below the warning triangle to indicate this (‘building’ may be varied to ‘buildings’ or ‘structure’)
🖼️ Where reduced headroom over a road is due to an overhanging building or structure, a plate may be added below the warning triangle to indicate this (‘building’ may be varied to ‘buildings’ or ‘structure’).
Roundels may also be incorporated into road works signs to indicate temporary height restrictions.
🖼️ Roundels may also be incorporated into road works signs to indicate temporary height restrictions.
Temporary or permanent reduction in bridge headroom ahead (temporary sign).
🖼️ Temporary or permanent reduction in bridge headroom ahead (temporary sign).

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✍️ Test 1 10 Qs ✍️ Test 2 10 Qs ✍️ Test 3 10 Qs ✍️ Test 4 10 Qs ✍️ Test 5 10 Qs ✍️ Test 6 10 Qs
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