Mandatory signsUnited States
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Mandatory signs
Information signsMandatory signs
A mandatory sign is a traffic sign that tells drivers what they must do. Instead of prohibiting actions, these signs impose obligations such as following a specific direction, using a particular lane, or keeping a minimum speed. Their purpose is to guide traffic safely and efficiently by ensuring that all road users follow the same required behaviour in places where it is necessary for order and safety.
How are compulsory instructions shown in the United States?
Regulatory signs also prescribe actions, such as lane-use directions and keeping right. Blue circles are not the general US convention.
What does a mandatory-direction or ONLY lane sign mean in the United States?
US regulatory signs such as the mandatory movement lane-control signs direct drivers in the indicated lane to make the movement shown. These can be rectangular signs with an arrow and the word ONLY; they are not necessarily European blue circles.
Does a mandatory-direction sign give me priority over pedestrians in the United States?
No. It tells you which way to move, not who goes first. Check traffic lights, other priority signs, pedestrians and cyclists, and give way when required before completing the manoeuvre.
1. Turning left mandatory
This traffic sign indicates that turning left is mandatory at the junction ahead. Traffic must turn left and may not continue straight ahead or turn right.
English • R3-5L • Left turn only. Traffic in the indicated lane must turn left.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: MUTCD, 11th Edition with Revision1, PDF page131
SVG source: Author not stated on source page • Public domain • Original revision 2023-07-22. Wikimedia original unmodified.
2. Turning right mandatory
This traffic sign indicates that turning right is mandatory at the junction ahead. Traffic must turn right and may not continue straight ahead or turn left.
English • R3-5R • Right turn only. Traffic in the indicated lane must turn right.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: MUTCD, 11th Edition with Revision1, PDF page131
SVG source: Author not stated on source page • Public domain • Original revision 2023-07-22. Wikimedia original unmodified.
3. Pass obstacle on the left
This traffic sign indicates that traffic must pass an obstacle on the left. Keep to the left of the obstacle and follow any accompanying signs or road markings.
English • R4-8b • Keep left. Pass to the left of the island or obstruction indicated by the sign.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: MUTCD, 11th Edition with Revision1, PDF page144
SVG source: Federal Highway Administration – United States Department of Transportation • Public domain • Original revision 2023-08-22. Wikimedia original unmodified.
4. Pass obstacle on the right
This traffic sign indicates that traffic must pass an obstacle on the right. Keep to the right of the obstacle and follow any accompanying signs or road markings.
English • R4-7b • Keep right. Pass to the right of the island or obstruction indicated by the sign.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: MUTCD, 11th Edition with Revision1, PDF page144
SVG source: Federal Highway Administration – United States Department of Transportation • Public domain • Original revision 2023-08-22. Wikimedia original unmodified.
Artwork verified against Mutcd.fhwa.dot.gov • official published diagram R4-7b.
5. Driving straight ahead mandatory
This traffic sign indicates that driving straight ahead is mandatory. Traffic must continue straight ahead and may not turn left or right at the location to which the sign applies.
English • R3-5a • Straight ahead only. Traffic in the indicated lane must continue straight ahead.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: MUTCD, 11th Edition with Revision1, PDF page131
SVG source: Author not stated on source page • Public domain • Original revision 2023-07-22. Wikimedia original unmodified.
6. Mandatory lane for trucks
This traffic sign indicates a mandatory lane for trucks. Trucks must use the designated lane where the sign applies. Other road users may use the lane only where the applicable signs or local rules permit them to do so.
English • R4-6 (legacy design) • Truck lane ahead. Indicates a truck lane beginning 500 feet ahead, as shown in the illustration. Follow the lane-use signs and markings at the lane. This is the legacy R4-6 design. It is documented in the earlier FHWA sign drawings and is not shown in the current MUTCD sign figures.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: earlier metric sign drawings, printed page1-66
SVG source: DelDot - State of Delaware • Public domain • Original revision 2012-09-20. Wikimedia original unmodified.
7. Start of a minimum speed
This traffic sign indicates the start of a minimum speed. Road users covered by the sign must travel at or above the indicated speed when conditions allow. Driving more slowly may still be necessary because of traffic, weather, road conditions or another safety-related reason.
English • R2-4a • Minimum speed. Sets a minimum speed of 40 mph, as shown in the illustration, subject to safety requirements and applicable law.
Sources
🔗 Commons.wikimedia.org
🔗 Mutcd.fhwa.dot.gov • FHWA: MUTCD, 11th Edition with Revision1, PDF page127
Image via Commons.wikimedia.org
Federal Highway Administration - MUTCD • Public domain • Source revision 2013-01-13. Wikimedia original unmodified.
