View source for 616.8 Temporary Traffic Control Zone Warning Signs (MUTCD Chapter 6H)

[[Category:616 Temporary Traffic Control (MUTCD Part 6)|616.08]]
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=={{SpanID|616.8.1}}616.8.1 Warning Sign Function, Design, and Application (MUTCD Section 6H.01) ==

'''Support. '''TTC zone warning signs notify road users of specific situations or conditions on or adjacent to a roadway that might not otherwise be apparent.

'''Standard. '''TTC warning signs shall comply with the Standards for warning signs presented in [[:Category:903 Highway Signing (MUTCD Part 2)|EPG 903]] and in the FHWA’s “Standard Highway Signs” publication (see [[:Category:911 General (MUTCD Part 1)#Relation_to_Other_Publications_(MUTCD_Section_1A.05)|EPG 911 (MUTCD Section 1A.05)]]). 

'''Support. '''The letter “O” is added to the TTC sign designation of WO and GO to represent the color orange, which provides a separate nomenclature from the permanent warning signs.

'''Standard. '''The sizes for TTC guide signs shall be as shown in [https://www.modot.org/media/16892 Standard Plan 616.10].

Except as provided in the first option paragraph below, TTC warning signs shall be diamond-shaped with a black legend and border on a fluorescent orange background, except for the Grade Crossing Advance Warning (WO10-1) sign, which shall have a black legend and border on a fluorescent yellow background. 

'''Option. '''Warning signs that are required or recommended in [[:Category:903 Highway Signing (MUTCD Part 2)|EPG 903]] or [[:Category:908 Traffic Controls for School Areas (MUTCD Part 7)|EPG 908]] to have a fluorescent yellow-green background may have that color background in TTC zones. 

Existing warning signs with a yellow background that are still applicable may remain in place. 

Warning signs used for TTC incident management situations may have a black legend and border on a fluorescent pink background.

Mounting or space considerations may justify a change from the standard diamond shape to a rectangular shape. 

In emergencies with coordination from district work zone coordinators, available warning signs having yellow backgrounds may be used if signs with orange or fluorescent pink backgrounds are not at hand.

'''Guidance. '''Where any part of the roadway is obstructed or closed by work activities or incidents, advance warning signs should be installed to alert road users well in advance of these obstructions or restrictions.

Where road users include pedestrians, the provision of supplemental audible information or detectable barriers or barricades should be provided for people with vision disabilities.

'''Support. '''Detectable barriers or barricades communicate very clearly to pedestrians who have vision disabilities that they can no longer proceed in the direction that they are traveling.

'''Option. '''Advance warning signs may be used singly or in combination.

Where distances are not displayed on warning signs as part of the message, a supplemental plaque with the distance legend may be mounted immediately below the sign on the same support.

=={{SpanID|616.8.2}}616.8.2 Position of Advance Warning Signs (MUTCD Section 6H.02) ==

'''Guidance. '''Where highway conditions permit, warning signs should be placed in advance of the transition and activity areas at varying distances depending on roadway type, condition, and posted speed. [[616.2 Temporary Traffic Control Elements (MUTCD Chapter 6B)#tab616.2.4|Table 616.2.4]] contains information regarding the spacing of advance warning signs. 

Where multiple advance warning signs are needed on the approach to a transition and activity area, the ROAD WORK AHEAD (WO20-1) sign should be the first advance warning sign encountered by road users.

'''Support. '''Various conditions, such as limited sight distance or obstructions that might require a driver to reduce speed or stop, might require additional advance warning signs.

'''Option. '''As an alternative to a specific distance on advance warning signs, the word AHEAD may be used.

Utility work, maintenance, or minor construction can occur within the TTC zone limits of a major construction project, and additional warning signs may be needed.

'''Guidance. '''Utility, maintenance, and minor construction signing and TTC should be coordinated with appropriate authorities so that road users are not confused or misled by the additional TTC devices.

=={{SpanID|616.8.3}}616.8.3 ROAD (BRIDGE) (RAMP) WORK Sign (WO20-1) (MUTCD Section 6H.03) ==
[[File:WO20-1.png|thumb|center|300px|alt=|<center>'''WO20-1'''</center>]]

'''Guidance. '''The ROAD (BRIDGE) (RAMP) WORK (WO20-1) sign, which serves as a general warning of obstructions or restrictions, should be located in advance of the work space or any detour, on the road where the work is taking place.

Where traffic can enter a TTC zone from a crossroad or a major (high-volume) driveway, an advance warning sign should be used on the crossroad or major driveway.

'''Option. '''The legend BRIDGE or RAMP may be substituted for ROAD and the distance legend may be either XX FEET, XX MILES, or AHEAD.

=={{SpanID|616.8.4}}616.8.4 DETOUR Sign (WO20-2) (MUTCD Section 6H.04)==
[[File:WO20-2.png|thumb|center|100px|alt=|<center>'''WO20-2'''</center>]]

'''Guidance. '''The DETOUR (WO20-2) sign should be used in advance of a road user detour over a different roadway or route.

The DETOUR sign should only be installed on the route being detoured. The DETOUR sign should not be used with temporary bypasses or connections unless part of or the entire route is over other existing roadways.

'''Option. '''The distance legend may be either XX FEET, XX MILES, or AHEAD. 

'''Support. '''See [[616.2 Temporary Traffic Control Elements (MUTCD Chapter 6B)#616.2.9|EPG 616.2.9]] for additional information regarding detour routes.

See [[616.9_Temporary_Traffic_Control_Zone_Guide_Signs_(MUTCD_Chapter_6I)#616.9.2_Detour_Signs_and_Plaques_(MO4-8P,_MO4-8a,_MO4-9,_MO4-9a,_MO4-9b,_MO4-9c,_and_MO4-10)_(MUTCD_Section_6I.02)|EPG 616.9.2]] for additional information regarding detour route signing.

=={{SpanID|616.8.5}}616.8.5 ROAD CLOSED Sign (WO20-3) (MUTCD Section 6H.05) ==
[[File:WO20-3.png|thumb|center|100px|alt=|<center>'''WO20-3'''</center>]]

'''Guidance. '''The ROAD CLOSED (WO20-3) sign should be used in advance of the point where a highway is closed to all road users, or to all but local road users. 

'''Option. '''The distance legend may be either XX FEET, XX MILES, or AHEAD.

=={{SpanID|616.8.6}}616.8.6 ONE LANE ROAD Sign (WO20-4) (MUTCD Section 6H.06)==
[[File:WO20-4.png|thumb|center|100px|alt=|<center>'''WO20-4'''</center>]]

'''Standard. '''The ONE LANE ROAD (WO20-4) sign shall be used only in advance of that point where motor vehicle traffic in both directions must use a common single lane (see [[616.5 One-Lane, Two-Way Traffic Control (MUTCD Chapter 6E)#616.5.1|EPG 616.5.1]]).

'''Option. '''The distance legend may be either XX FEET, XX MILES, or AHEAD.

=={{SpanID|616.8.7}}616.8.7 Lane(s) Closed Signs (WO20-5, WO20-5a, and WO9-3) (MUTCD Section 6H.07) ==
<center>
{|
| [[File:WO20-5.png|thumb|center|100px|alt=|<center>'''WO20-5'''</center>]]
| [[File:WO20-5a.png|thumb|center|100px|alt=|<center>'''WO20-5a'''</center>]]
| [[File:WO9-3.png|thumb|center|100px|alt=|<center>'''WO9-3'''</center>]]
|}
</center>
'''Standard. '''The Lane(s) Closed sign shall be used in advance of that point where one or more through lanes of a multi-lane roadway are closed.

For a single lane closure, the Lane Closed (WO20-5) sign shall use the legend RIGHT (LEFT) LANE CLOSED. Where two or more adjacent lanes are closed, the WO20-5a sign shall use the legend XX RIGHT (LEFT) LANES CLOSED. 

'''Option. '''The distance legend may be either XX FEET, XX MILES, or AHEAD. 

'''Guidance. '''The Interior Lane Shift (WO9-3) sign should be used in advance of that point where work occupies an interior lane(s) and approaching motor vehicle traffic is directed to the right or left of the work zone in the lane(s) by using a shifting taper to route traffic around the closed interior lane(s).

=={{SpanID|616.8.8}}616.8.8 Lane Ends Signs (WO4-2 and WO9-2a) (MUTCD Section 6H.08)==
<center>
{|
| [[File:WO4-2.png|thumb|center|100px|alt=|<center>'''WO4-2'''</center>]]
| [[File:WO9-2a.png|thumb|center|150px|alt=|<center>'''WO9-2a'''</center>]]
|}
</center>

'''Option. '''The Lane Ends (WO4-2) sign may be used to warn drivers of the reduction in the number of lanes for moving motor vehicle traffic in the direction of travel on a multi-lane roadway.

'''Guidance. '''The MERGE HERE TAKE TURNS (WO9-2a) sign should be used to identify the merge point at which vehicles from alternate lanes take turns merging during Late Merge applications (see [[616.14 Types of Temporary Traffic Control Zone Activities (MUTCD Chapter 6N)#616.14.19|EPG 616.14.19]]).

=={{SpanID|616.8.9}}616.8.9 ON RAMP Plaque (WO13-4P) (MUTCD Section 6H.09) ==
[[File:WO13-4P.png|thumb|center|90px|alt=|<center>'''WO13-4P'''</center>]]

'''Guidance. '''When work is being done on a ramp, but the ramp remains open, the ON RAMP (WO13-4P) plaque should be used to supplement the advance ROAD WORK sign.

'''Support. '''It may not be possible to install an ON RAMP plaque on signs mounted for short duration or mobile operations.

=={{SpanID|616.8.10}}616.8.10 RAMP NARROWS Sign (WO5-4) (MUTCD Section 6H.10)==
[[File:WO5-4.png|thumb|center|200px|alt=|<center>'''WO5-4'''</center>]]


'''Guidance. '''The RAMP NARROWS (WO5-4) sign should be used in advance of the point where work on a ramp reduces the normal width of the ramp along a part or all of the ramp.

'''Support. '''See [[903.3 Warning Signs and Object Markers (MUTCD Chapter 2C)#903.3.15|EPG 903.3.15]] for additional information regarding the ROAD NARROWS (WO5-1) sign.

See [[903.3 Warning Signs and Object Markers (MUTCD Chapter 2C)#903.3.16|EPG 903.3.16]] for additional information regarding the NARROW BRIDGE (WO5-2) sign.

=={{SpanID|616.8.11}}616.8.11 EXIT GORE sign (EO5-1)==
[[File:EO5-1.png|thumb|center|100px|alt=|<center>'''EO5-1'''</center>]]


'''Guidance. '''Temporary EXIT GORE (EO5-1) signs should be provided when work in the vicinity of off-ramps shifts the gore point of the ramp.

=={{SpanID|616.8.12}}616.8.12 EXIT OPEN and EXIT CLOSED Signs (EO5-2 and EO5-2a) (MUTCD Section 6H.12)==
<center>
{|
| [[File:EO5-2.png|thumb|center|100px|alt=|<center>'''EO5-2'''</center>]]
| [[File:EO5-2a.png|thumb|center|100px|alt=|<center>'''EO5-2a'''</center>]]
|}
</center>

'''Option. '''An EXIT OPEN (EO5-2) or EXIT CLOSED (EO5-2a) sign may be used to supplement other warning signs where work is being conducted in the vicinity of an exit ramp and where the exit maneuver for vehicular traffic using the ramp is different from the normal condition.

=={{SpanID|616.8.13}}616.8.13 Flagger Sign (WO20-7) (MUTCD Section 6H.15) ==
[[File:WO20-7.png|center|120px|thumb|<center>'''WO20-7'''</center>]]

'''Guidance. '''The Flagger (WO20-7) sign should be used in advance of any point where a flagger is stationed to control road users. These signs should be displayed when a flagger is present and should be covered or removed when the flagger is not present.

'''Option. '''The flagger sign may be used in conjunction with the BE PREPARED TO STOP (WO3-4) sign.

=={{SpanID|616.8.14}}616.8.14 BE PREPARED TO STOP sign (WO3-4)==
[[File:WO3-4.png|center|110px|thumb|<center>'''WO3-4'''</center>]]

'''Option. '''The BE PREPARED TO STOP (WO3-4) sign may be used where conditions require traffic to stop for flagger-controlled truck/equipment crossings or entrances and temporary road closures where traffic is allowed to proceed unimpeded until access is needed. This sign may also be used in one-lane, two-way flagging operations where no work zone speed limit is established.

=={{SpanID|616.8.15}}616.8.15 Two-Way Traffic Sign (WO6-3) (MUTCD Section 6H.16) ==

[[File:WO6-3.png|center|115px|thumb|<center>'''WO6-3'''</center>]]

'''Guidance. '''When one roadway of a normally-divided highway is closed, with two-way vehicular traffic maintained on the other roadway, the Two-Way Traffic (WO6-3) sign should be used at the beginning of the two-way vehicular traffic section and at intervals to remind road users of opposing vehicular traffic.

=={{SpanID|616.8.16}}616.8.16 Workers Signs (WO21-1 and WO21-1a) (MUTCD Section 6H.18)==
<center>
{|
| [[File:WO21-1.png|thumb|center|120px|alt=|<center>'''WO21-1'''</center>]]
| [[File:WO21-1a.png|thumb|center|120px|alt=|<center>'''WO21-1a'''</center>]]
|}
</center>

'''Option. '''A Workers (WO21-1) sign may be used to alert road users of workers in or near the roadway.

'''Guidance. '''In the absence of other warning devices, a Workers sign should be used when workers are in the roadway.

'''Option. '''The WORKERS (WO21-1a) word message sign may be used as an alternate to the Workers (W21-1) symbol sign.

=={{SpanID|616.8.17}}616.8.17 Surface Condition Signs (WO21-2 and WO8-7) (MUTCD Section 6H.19) ==
<center>
{|
| [[File:WO21-2.png|thumb|center|120px|alt=|<center>'''WO21-2'''</center>]]
| [[File:WO8-7.png|thumb|center|120px|alt=|<center>'''WO8-7'''</center>]]
| [[File:WO8-7a.png|thumb|center|150px|alt=|<center>'''WO8-7a'''</center>]]
|}
</center>

'''Guidance. '''The FRESH OIL (WO21-2), LOOSE GRAVEL (WO8-7), and FRESH OIL/LOOSE GRAVEL signs should be used to warn road users of the surface treatment.

=={{SpanID|616.8.18}}616.8.18 Motorized Traffic Signs (WO8-6 and WO8-6c) (MUTCD Section 6H.21) ==
<center>
{|
| [[File:WO8-6.png|thumb|center|120px|alt=|<center>'''WO8-6'''</center>]]
| [[File:WO8-6c.png|thumb|center|120px|alt=|<center>'''WO8-6c'''</center>]]
|}
</center>

'''Option. '''TRUCK CROSSING (WO8-6) and TRUCK ENTRANCE (WO8-6c) signs may be used to alert road users to locations where unexpected travel on the roadway or entries into or departures from the roadway by construction vehicles might occur.

'''Support''': These locations might be relatively confined or might occur randomly over a segment of roadway.

=={{SpanID|616.8.19}}616.8.19 Shoulder Work Signs (WO21-5, WO21-5a, and WO21-5b)(MUTCD Section 6H.22)==
<center>
{|
| [[File:WO21-5.png|thumb|center|150px|alt=|<center>'''WO21-5'''</center>]]
| [[File:WO21-5a.png|thumb|center|150px|alt=|<center>'''WO21-5a'''</center>]]
| [[File:WO21-5b.png|thumb|center|150px|alt=|<center>'''WO21-5b'''</center>]]
|}
</center>

'''Support. '''Shoulder Work signs warn of maintenance, reconstruction, or utility operations on the highway shoulder where the roadway is unobstructed.

'''Standard. '''The Shoulder Work sign shall have the legend SHOULDER WORK (WO21-5), RIGHT (LEFT) SHOULDER CLOSED (WO21-5a), or RIGHT (LEFT) SHOULDER CLOSED XX FT or AHEAD (WO21-5b).

'''Option. '''The Shoulder Work sign may be used in advance of the point on a non-limited access highway where there is shoulder work. It may be used singly or in combination with a ROAD WORK NEXT XX MILES or ROAD WORK AHEAD sign.

'''Guidance. '''On freeways and expressways, the RIGHT (LEFT) SHOULDER CLOSED XX FT or AHEAD (WO21-5b) sign followed by RIGHT (LEFT) SHOULDER CLOSED (WO21-5a) sign should be used in advance of the point where the shoulder work occurs and should be preceded by a ROAD WORK AHEAD sign.

=={{SpanID|616.8.20}}616.8.20 SURVEY CREW Sign (WO21-6) (MUTCD Section 6H.23) ==
[[File:WO21-6.png|thumb|center|150px|alt=|<center>'''WO21-6'''</center>]]

'''Guidance. '''The SURVEY CREW (WO21-6) sign should be used to warn of surveying crews working in or adjacent to the roadway.

=={{SpanID|616.8.21}}616.8.21 UTILITY WORK Sign (WO21-7) (MUTCD Section 6H.24)==
[[File:WO21-7.png|thumb|center|150px|alt=|<center>'''WO21-7'''</center>]]

'''Option. '''For permit projects, the UTILITY WORK (WO21-7) sign may be used as an alternate to the ROAD (STREET) WORK (WO20-1) sign for utility operations on or adjacent to a highway.

The distance legend may be either XX FEET, XX MILES, or AHEAD.

=={{SpanID|616.8.22}}616.8.22 Signs for Blasting Areas ==

'''Support. '''These signs are not shown on the traffic control plan due to the various methods of detonation and various locations within a project that may require blasting. Reference to Blasting Area requirements are located in the following: [https://www.modot.org/missouri-standard-specifications-highway-construction| Specification Section 616], [[:Category:203 Roadway and Drainage Excavation, Embankment and Compaction|EPG 203]], MUTCD Section 6H.25, and MUTCD TA-2.

'''Standard. '''Road users shall be warned where blasting operations occur. A sequence of signs shall be prominently displayed to warn all road users of blasting operations and to direct operators of mobile radio equipment, including cellular telephones, to turn off transmitters in a blasting area. These signs shall be covered or removed when there are no explosives in the area or the area is otherwise secured.

=={{SpanID|616.8.23}}616.8.23 Shoulder Signs and Plaque (WO8-4, WO8-17, and WO8-17P) (MUTCD Section 6H.26) ==
<center>
{|
| [[File:WO8-4.png|thumb|center|150px|alt=|<center>'''WO8-4'''</center>]]
| [[File:WO8-17.png|thumb|center|150px|alt=|<center>'''WO8-17'''</center>]]
| [[File:WO8-17P.png|thumb|center|90px|alt=|<center>'''WO8-17P'''</center>]]
|}
</center>

'''Option. '''The SOFT SHOULDER (WO8-4) sign may be used to warn of a soft shoulder condition.

'''Guidance. '''The Shoulder Drop Off (WO8-17) sign should be used when an unprotected shoulder drop-off, adjacent to the travel lane, exceeds 2 inches in depth for a continuous length along the roadway, based on engineering judgment.

When the SHOULDER DROP-OFF signs are installed for greater than three days, the SHOULDER DROP-OFF (W8-17P) supplemental plaque should be mounted below the W8-17sign.

=={{SpanID|616.8.24}}616.8.24 UNEVEN LANES Sign (WO8-11) (MUTCD Section 6H.27) ==
[[File:WO8-11.png|thumb|center|150px|alt=|<center>'''WO8-11'''</center>]]

'''Guidance. '''The UNEVEN LANES (WO8-11) sign should be used during operations that create a difference in elevation between adjacent lanes that are open to travel. 

'''Support. '''This sign is to be used as shown in [https://www.modot.org/media/16895 Standard Plans 619.10] and [https://www.modot.org/media/16897 620.10].

=={{SpanID|616.8.25}}616.8.25 STEEL PLATE AHEAD Sign (WO8-24) (MUTCD Section 6H.28) ==
[[File:WO8-24.png|thumb|center|150px|alt=|<center>'''WO8-24'''</center>]]


'''Option. '''Unprotected excavations or repairs located within a roadway are usually backfilled when workers are not present, but may also be covered with steel plates. While plating is generally used by Maintenance employees on low speed (under 45 mph) roadways, it may also be appropriate within contract and permit work zones. A design exception may be needed to use steel plates in contract and permit work zones.

'''Guidance. '''When steel plates are used, STEEL PLATE AHEAD (WO8-24) signs should be used to warn road users that the presence of a temporary steel plate(s) might make the road surface uneven and might create slippery conditions during wet weather (see [[616.16 Typical Applications (MUTCD Chapter 6P)#616.16|TA-47]]).

In any case, the plate must be appropriately sized to adequately conduct the vehicular loading and must be delineated according to the diagram below. Only 3/4 in. of the plate’s overall thickness may protrude above the roadway surface and the height differential must be transitioned at a rate no steeper than 3H:1V around the entire perimeter. This may be accomplished by beveling the plate, wedging asphalt or mechanically fastening, as approved by the engineer. Care must be taken to ensure that a mechanical fastener is appropriate for the operating speed of the work zone. The surface of the plate must be treated for skid resistance, either by surface deformation or direct application of a friction course.

'''Support. '''See [[#fig616.8.25|Figure 616.8.25]] for markings to be used on steel plates.

{{SpanID|fig616.8.25}}
[[File:Figure 616.8.25 Examples of Markings on Steel Plates.jpg|center|740px|alt="The figure shows two rectangular steel plates with examples of white reflective markings applied near the corners. The left diagram represents steel plates with any side 6 feet or longer. It includes four L-shaped white reflective tape or paint markings, each 4 inches wide. These markings are placed approximately 3 inches from the edges. Each L-shape measures 2.5 feet in width and 2.5 feet in length. The L-shaped markers are located at the corners of the plate.

The right diagram represents steel plates with any side shorter than 6 feet. It also includes four L-shaped reflective markings, each 4 inches wide. These markings are placed approximately 3 inches from the edges. Each L-shape measures 1 foot in width and 1 foot in length. The L-shaped markers are located at the corners of the plate."
|thumb|
{| style="margin: 1em auto 1em auto"
|-
|'''Steel plates with any side ≥ 6' long'''||width=120| || '''Steel plates with any side < 6' long'''
|}
'''Figure 616.8.25''' Examples of Markings on Steel Plates]]

=={{SpanID|616.8.26}}616.8.26 NO CENTER LINE Sign (WO8-12) (MUTCD Section 6H.29)==

[[File:WO8-12.png|thumb|center|150px|alt=|<center>'''WO8-12'''</center>]]

'''Support. '''The NO CENTER LINE (WO8-12) sign is a black-on-orange warning sign used on two-lane and two-lane with auxiliary lane facilities where centerline marking is eliminated for 200 linear ft. or more. These signs are used in combination with temporary pavement marking. These signs are placed in advance of the missing centerline markings area at the recommended sign spacing. 

'''Guidance. '''For extended areas continuously or intermittently missing centerline marking, NO CENTER LINE signs should also be installed within 150 ft. after the intersection of a state route and at two-mile spacing throughout the affected area. 

'''Option. '''Upon the discretion of the engineer or supervisor, additional NO CENTER LINE signs may be installed within 150 ft. after other intersections. 

When a sign placed at the two-mile interval and another sign placed after an intersection fall within one-eighth mile of each other, the sign placed at the two-mile interval may be eliminated. 

'''Support. '''[https://www.modot.org/media/16897 Standard Plan 620.10] shows the configuration for these signs and pavement markers on a two-lane roadway. This layout is to also be included in the TCP.

'''Standard. '''When temporary pavement markings and/or NO CENTER LINE signs are necessitated by either a change in roadway use or the elimination of permanent pavement markings, the following provisions shall be incorporated into the operation:
:A. Those performing the operation shall be responsible for coordinating the procurement, installation, maintenance and removal, as applicable, of pavement markings, temporary or permanent, and any NO CENTER LINE signs.
:B. Temporary pavement markings and any NO CENTER LINE signs shall be in place prior to opening a roadway to traffic. On two-lane highways with AADTs less than 1000, when certain material and operations do not allow the practical application of these markings (e.g., seal coat, cold mix curing, fly coating, etc.), installation of temporary pavement markings may be delayed up to 5 working days, initiated by the elimination of the permanent pavement markings, provided the required NO CENTER LINE signs are in place as prescribed previously prior to opening the facility to traffic.
:C. For Contract Projects – Permanent pavement marking shall be installed in accordance with [http://www.modot.org/business/standards_and_specs/SpecbookEPG.pdf#page=9 Section 620 Pavement Marking].
:D. For Maintenance Operations – Permanent pavement markings should be installed no later than 14 calendar days after any operation has been completed. However, delays in installation should be minimized where possible.
:E. Removal or obliteration of all pavement markings shall be complete and leave minimal pavement scarring. Concealing any pavement marking with black paint or asphalt is not acceptable.

=={{SpanID|616.8.27}}616.8.27 Reverse Curve Signs (WO1-4 Series) (MUTCD Section 6H.30) ==

<center>

{|
| [[File:WO1-4.png|thumb|center|100px|alt=|<center>'''WO1-4'''</center>]]
| [[File:WO1-4b.png|thumb|center|100px|alt=|<center>'''WO1-4b'''</center>]]
| [[File:WO1-4c.png|thumb|center|100px|alt=|<center>'''WO1-4c'''</center>]]
|}

</center>

'''Guidance. '''In order to give road users advance notice of a lane shift, a Reverse Curve (WO1-4, WO1-4b, or WO1-4c) sign should be used when a lane (or lanes) is being shifted to the left or right. If the design speed of the curves is 30 mph or less, a Reverse Turn (WO1-3) sign should be used.

'''Standard. '''If a Reverse Curve (or Turn) sign is used, the direction of the reverse curve (or turn) shall be appropriately illustrated. Except as provided in the following option paragraph, the number of lanes illustrated on the sign shall be the same as the number of through lanes available to road users.

'''Option. '''Where two or more lanes are being shifted, a WO1-4 (or WO1-3) sign with an ALL LANES (WO24-1cP) plaque may be used instead of a sign that illustrates the number of lanes.

Where more than three lanes are being shifted, the Reverse Curve (or Turn) sign may be rectangular.

'''Support. '''See [[903.3 Warning Signs and Object Markers (MUTCD Chapter 2C)#903.3.7|EPG 903.3.7]] for information regarding Turn and Curve signs.

=={{SpanID|616.8.28}}616.8.28 Large Arrow Signs (WO1-6 and WO1-7) ==
<center>
{|
| [[File:WO1-6.jpg|thumb|center|100px|alt=|<center>'''WO1-6'''</center>]]
| [[File:WO1-7.jpg|thumb|center|100px|alt=|<center>'''WO1-7'''</center>]]
|}
</center>

'''Support. '''The One-Direction Large Arrow (WO1-6) sign and the Two-Direction Large Arrow (WO1-7) sign are used in conjunction with Type 3 barricades. The WO1-6 sign is also used in conjunction with the Turn (WO1-1) sign and the Reverse Turn (WO1-3) sign.

=={{SpanID|616.8.29}}616.8.29 Double Reverse Curve Signs (WO24-1 Series) (MUTCD Section 6H.31)==
<center>
{|
| [[File:WO24-1.png|thumb|center|100px|alt=|<center>'''WO24-1'''</center>]]
| [[File:WO24-1a.png|thumb|center|100px|alt=|<center>'''WO24-1a'''</center>]]
| [[File:WO24-1b.png|thumb|center|100px|alt=|<center>'''WO24-1b'''</center>]]
| [[File:WO24-1cP.png|thumb|center|100px|alt=|<center>'''WO24-1cP'''</center>]]
|}
</center>

'''Option. '''The Double Reverse Curve (WO24-1, WO24-1a, or WO24-1b) sign may be used where the tangent distance between two reverse curves is less than 600 feet, thus making it difficult for a second Reverse Curve (WO1-4 series) sign to be placed between the curves. If the design speed of the curves is 30 mph or less, Double Reverse Turn signs may be used.

'''Standard. '''If a Double Reverse Curve (or Turn) sign is used, the direction of the double reverse curve (or turn) shall be appropriately illustrated. Except as provided in the following option paragraph, the number of lanes illustrated on the sign shall be the same as the number of through lanes available to road users.

'''Option. '''Where two or more lanes are being shifted, a WO24-1 (or Double Reverse Turn sign showing one lane) sign with an ALL LANES (WO24-1cP) plaque may be used instead of a sign that illustrates the number of lanes.

Where more than three lanes are being shifted, the Double Reverse Curve (or Turn) sign may be rectangular.

=={{SpanID|616.8.30}}616.8.30 Advisory Speed Plaque (WO13-1P) (MUTCD Section 6H.32)==
[[File:WO13-1P.png|thumb|center|80px|alt=|<center>'''WO13-1P'''</center>]]

'''Option. '''In combination with a warning sign, an Advisory Speed (WO13-1P) plaque may be used to indicate a recommended speed for a change in horizontal alignment or through a signed condition within a TTC zone.

'''Standard. '''The Advisory Speed plaque shall not be used in conjunction with any sign other than a warning sign, nor shall it be used alone. When used with orange TTC zone signs, this plaque shall have a black legend and border on an orange background.

'''Support. '''Warning signs with advisory speed plaques (see [[903.3 Warning Signs and Object Markers (MUTCD Chapter 2C)#903.3.59|EPG 903.3.59]]) inform drivers of the recommended operating speed based on temporary conditions within a TTC zone. Examples include narrow lanes, temporary diversion (reverse curves), lane shifts, sight distance restrictions, rough road surface, bumps, low/no shoulder, workers on foot, work vehicles or equipment close to the open travel lane, or other conditions that indicate the need for reduced speed.

AASHTO and ITE design documents contain established engineering practices for the determination of the recommended advisory speeds for horizontal curves or locations with limited sight distance.

=={{SpanID|616.8.31}}616.8.31 Supplementary Distance Plaque (WO7-3aP) (MUTCD Section 6H.33) ==
[[File:WO7-3aP.png|thumb|center|100px|alt=|<center>'''WO7-3aP'''</center>]]

'''Option.''' In combination with a warning sign, a Supplementary Distance (WO7-3aP) plaque with the legend NEXT XX MILES may be used to indicate the length of highway over which a work activity is being conducted, or over which a condition exists in the TTC zone.

In long TTC zones, Supplementary Distance plaques with the legend NEXT XX MILES may be placed in combination with warning signs at regular intervals within the zone to indicate the remaining length of highway over which the TTC work activity or condition exists.

'''Standard. '''The Supplementary Distance plaque with the legend NEXT XX MILES shall not be used in conjunction with any sign other than a warning sign, nor shall it be used alone. When used with orange TTC zone signs, this plaque shall have a black legend and border on an orange background.

'''Guidance. '''When used in TTC zones, the Supplementary Distance plaque with the legend NEXT XX MILES should be placed below the initial warning sign designating that, within the approaching zone, a temporary work activity or condition exists.

=={{SpanID|616.8.32}}616.8.32 Motorcycle Plaque (WO8-15aP) (MUTCD Section 6H.34) ==
[[File:WO8-15aP.png|thumb|center|100px|alt=|<center>'''WO8-15aP'''</center>]]

'''Option. '''A Motorcycle (WO8-15aP) plaque may be mounted below a GROOVED PAVEMENT (WO8-15) sign if the warning is intended to be directed primarily to motorcyclists.

'''Standard. '''When the GROOVED PAVEMENT (WO8-15) sign is in place for greater than three days, the Motorcycle (WO8-15Pa) plaque shall be used in addition to the WO8-15 sign.

=={{SpanID|616.8.33}}616.8.33 ROAD WORK NEXT XX MILES Sign (GO20-1) (MUTCD Section 6H.35)==
[[File:GO20-1.png|thumb|center|100px|alt=|<center>'''GO20-1'''</center>]]

'''Guidance. '''The ROAD WORK NEXT XX MILES (GO20-1) sign should be installed in advance of TTC zones that are more than 2 miles in length. 

'''Option. '''The ROAD WORK NEXT XX MILES (GO20-1) sign may be used to warn road users of a downstream lane addition or head-to-head lane reconstruction. Examples of projects where this sign is not to be installed include new alignment, guardrail replacement, or those with mobile operations. 

The ROAD WORK NEXT XX MILES sign may be mounted on a Type 3 Barricade. The sign may also be used for TTC zones of shorter length.

'''Standard. '''The distance displayed on the ROAD WORK NEXT XX MILES sign shall be stated to the nearest whole mile.

=={{SpanID|616.8.34}}616.8.34 END ROAD WORK Sign (GO20-2) (MUTCD Section 6H.36)==
[[File:GO20-2.png|thumb|center|100px|alt=|<center>'''GO20-2'''</center>]]

'''Guidance. '''When used, the END ROAD WORK (G20-2) sign should be placed near the downstream end of the termination area, as determined by engineering judgment when the ROAD WORK NEXT XX MILES sign is used.

'''Option. '''The END ROAD WORK sign may be installed on the back of a warning sign facing the opposite direction of road users or on the back of a Type 3 Barricade.

=={{SpanID|616.8.35}}616.8.35 PILOT CAR FOLLOW ME Sign (GO20-4) and PILOT CAR IN USE WAIT & FOLLOW (GO20-4a) (MUTCD Section 6H.37) ==
<center>
{|
| [[File:GO20-4.png|thumb|center|100px|alt=|<center>'''GO20-4'''</center>]]
| [[File:GO20-4a.png|thumb|center|100px|alt=|<center>'''GO20-4a'''</center>]]
|}
</center>

'''Standard. '''The PILOT CAR FOLLOW ME (GO20-4) sign shall be mounted in a conspicuous position on the top or on the rear of a vehicle used for guiding one-way vehicular traffic through or around a TTC zone (see [[616.5 One-Lane, Two-Way Traffic Control (MUTCD Chapter 6E)#616.5.4|EPG 616.5.4]]).

'''Standard. '''The 42 x 30 inch PILOT CAR IN USE WAIT & FOLLOW (GO20-4a) shall be used on all state routes.

'''Option. '''The 42 x 30 inch PILOT CAR IN USE WAIT & FOLLOW (GO20-4a) may be used on any non-state routes, as determined by the engineer.

'''Guidance. '''The 18 x 12 inch PILOT CAR IN USE WAIT & FOLLOW (GO20-4a) should be used on all other non-state routes (city streets, county roads, etc.).

=={{SpanID|616.8.36}}616.8.36 Other Warning Signs (MUTCD Section 6H.38) ==

'''Option. '''Advance warning signs may be used by themselves or with other advance warning signs.

Besides the warning signs specifically related to TTC zones, several other warning signs in [[:Category:903 Highway Signing (MUTCD Part 2)|EPG 903]] may apply in TTC zones.

Word message warning signs other than those classified and specified in the EPG and the FHWA’s “Standard Highway Signs” publication (see [[:Category:911 General (MUTCD Part 1)#Relation_to_Other_Publications_(MUTCD_Section_1A.05)|EPG 911 (MUTCD Section 1A.05)]]) may be developed and used based on engineering judgment to warn of special conditions in TTC zones. 

'''Standard. '''Except as provided in [[616.6 Temporary Traffic Control Zone Signs - General (MUTCD Chapter 6F)#616.6.1|EPG 616.6.1]] and [[616.8_Temporary_Traffic_Control_Zone_Warning_Signs_(MUTCD_Chapter_6H)#616.8.1_Warning_Sign_Function,_Design,_and_Application_(MUTCD_Section_6H.01)|EPG 616.8.1]], other warning signs that are used in TTC zones shall have black legends and borders on a fluorescent orange background.

'''Guidance. '''Other warning signs should comply with the general requirements of color, shape, and alphabet size and series. The sign message should be brief, legible, and clear.

=={{SpanID|616.8.37}}616.8.37 Reduced Speed Limit Ahead (WO3-5)==
[[File:WO3-5.png|thumb|center|100px|alt=|<center>'''WO3-5'''</center>]]

'''Standard. '''The Reduced Speed Limit Ahead (WO3-5) sign shall be used when the geometrics of the roadway require an approved speed reduction greater than 10 mph below the existing or posted speed limit.

'''Support. '''If the geometrics of the roadway require a 10 mph speed reduction at the beginning of the project and construction work requires an additional 5 to 10 mph reduction farther down the road, then the WO3-5 sign is not required. 

'''Standard. '''The Reduced Speed Limit Ahead (WO3-5) sign shall be followed by a SPEED LIMIT (R2-1) sign. The speed limit indicated on the REDUCDED SPEED LIMIT AHEAD sign shall be identical to the SPEED LIMIT sign (see [[616.18 Work Zone Speed Limits|EPG 616.18]]).

=={{SpanID|616.8.38}}616.8.38 GROOVED PAVEMENT (WO8-15)==
[[File:WO8-15.png|thumb|center|100px|alt=|<center>'''WO8-15'''</center>]]

'''Standard. '''When cold-milled areas are left opened to traffic, the GROOVED PAVEMENT (WO8-15) sign shall be used in locations described in [https://www.modot.org/missouri-standard-specifications-highway-construction Specifications Section 622]. 

'''Support. '''Since designers cannot estimate the various times a contractor may leave a milled area opened to traffic, these signs are not shown on the traffic control plan. These signs, if used, are furnished by the contractor at the contractor's expense.

'''Standard. '''When the GROOVED PAVEMENT (WO8-15) sign is in place for greater than three days, the Motorcycle (WO8-15aP) plaque shall be used in addition to the WO8-15 sign.

=={{SpanID|616.8.39}}616.8.39 NARROW LANES (WO5-5)==
[[File:WO5-5.png|thumb|center|100px|alt=|<center>'''WO5-5'''</center>]]

'''Option. '''The NARROW LANES (WO5-5) sign may be used on multilane highways where the lane width is temporarily reduced.

=={{SpanID|616.8.40}}616.8.40 Vehicle Speed Feedback System (Radar Speed Advisory System)==

'''Option. '''A Vehicle Speed Feedback (WO13-20aP) plaque (see [[#fig616.8.40|Figure 616.8.40]]) that displays the speed of an approaching vehicle to the vehicle operator may be used to provide warning to drivers of their speed in relation to a speed limit (R2-1) sign within a TTC zone.

'''Standard. '''When used to display the speed of an approaching vehicle in relation to the posted speed limit, the Vehicle Speed Feedback (WO13-20aP) plaque shall be mounted below a Speed Limit (R2-1) sign (see [[903.2 Regulatory Signs and Barricades (MUTCD Chapter 2B)#903.2.20|EPG 903.2.20]]).

The Vehicle Speed Feedback assembly shall not be installed at a location where the posted speed limit on the route changes. Vehicle Speed Feedback assemblies shall be placed anywhere downstream of a speed limit change but shall be a minimum of 200 feet downstream of a speed limit change on conventional routes and a minimum of 400 feet downstream of a speed limit change on expressways of freeways. Vehicle Speed Feedback assemblies shall be installed in accordance with the Vehicle Speed Feedback Assembly Typical Application.

The legend YOUR SPEED shall be a black legend on a fluorescent orange retroreflective background. The changeable legend displaying the speed of the approaching vehicle shall be a yellow or orange luminous legend on a black opaque background. The vehicle speed displayed on the changeable portion of the sign shall be displayed as an integer. The Vehicle Speed Feedback plaque shall not flash, strobe, change color, or use other animated elements integrated into the changeable legend display. When no vehicles are approaching, the changeable display shall not display a legend. 

Vehicle Speed Feedback sign equipment shall not have the capability to collect, store or transmit personally identifiable information of any type.

'''Guidance. '''The changeable portion of the Vehicle Speed Feedback legend should be approximately the same height, width, and stroke of those on the Speed Limit sign it supplements or is mounted below.

When a WO13-20aP plaque is used with a Speed Limit sign it should be approximately the same width as the Speed Limit sign it is mounted below. 

'''Support. '''A nonstandard JSP, [https://epg.modot.org/forms/JSP/NJSP2106.docx NJSP 21-06 ], has been created for the Radar Speed Advisory System (RSAS).

See [[907.8 Speed Trailers Deployed by Others|EPG 907.8]] for additional information.

{{SpanID|fig616.8.40}}
[[File:Figure 616.8.40 Vehicle Speed Feedback Plaque.png|thumb|center|250px|alt=The figure shows an example assembly of a work zone speed feedback display. At the top is an orange rectangular sign labeled “WORK ZONE” with a black border, identified as sign GO20-5aP. Below it is a standard white speed limit sign with the message “SPEED LIMIT 35.” Beneath the speed limit sign is an orange electronic feedback sign labeled “YOUR SPEED,” displaying the number “42” in illuminated yellow digits; this sign is identified as WO13-20aP. A note below the assembly states that the supplemental plaque is installed below a speed limit sign and is used downstream of speed limit changes or within a speed zone to reaffirm the speed limit.
|'''Figure 616.8.40''' Vehicle Speed Feedback Plaque]]

=={{SpanID|616.8.41}}616.8.41 Object Markers (MUTCD Section 6H.43)==

'''Support. '''Object markers are used in work zones to mark temporary obstructions within or adjacent to the roadway (see [[903.3 Warning Signs and Object Markers (MUTCD Chapter 2C)#903.3.73|EPG 903.3.73]]).'''

'''Standard. '''A Type 1 Object Marker shall be attached to the lead module of sand-filled impact attenuators. 

'''Option. '''Type 3 Object Markers may be used to supplement other channelizing devices in special situations.