903.6 Warning Signs

903.6.1 Function of Warning Signs (MUTCD Section 2C.01)

Support. Warning signs call attention to unexpected conditions on or adjacent to a highway or street and to situations that might not be readily apparent to road users. Warning signs alert road users to conditions that might call for a reduction of speed or an action in the interest of safety and efficient traffic operations.

903.6.2 Application of Warning Signs (MUTCD Section 2C.02)

Standard. The use of warning signs shall be based on an engineering study or on engineering judgment.

Guidance. The use of warning signs should be kept to a minimum as the unnecessary use of warning signs tends to increase disrespect for all signs. In situations where the condition or activity is seasonal or temporary, the warning sign should be removed or covered when the condition or activity does not exist.

Support. Warning signs specified herein cover most of the conditions that are likely to be encountered. Additional warning signs for temporary traffic control zones, school areas, highway-rail grade crossings, bicycle facilities and highway-light rail transit grade crossings are discussed in 903.6.16 through 903.6.17, 616.2.2 Warning Signs and 641.1 Bicycle Facilities.

Option. Word message warning signs other than those specified in this manual may be developed and installed.

903.6.3 Design of Warning Signs (MUTCD Section 2C.03)

Standard. All warning signs shall be diamond-shaped (square with one diagonal vertical) with a black legend and border on a yellow background unless specifically designated otherwise. Warning signs shall be designed in accordance with the sizes, shapes, colors and legends contained in Standard Highway Signs.

Option. Warning signs regarding conditions associated with pedestrians, bicyclists, playgrounds, school buses and schools may have a black legend and border on a yellow background or a black legend and border on a fluorescent yellow-green background.

Table 903.6.3 Warning Sign Sizes

(Sheet 1 of 4)

Sign	Sign Number	Article	Conventional	Expressway (At Grade)	Freeway (Grade Separated)	Other
TURN	W1-1R(L)	903.6.7	36 x 36	48 x 48	-	-
CURVE	W1-2R(L)	903.6.7	36 x 36	48 x 48	-	-
REVERSE TURN	W1-3R(L)	903.6.7	36 x 36	48 x 48	-	-
REVERSE CURVE	W1-4R(L)	903.6.7	36 x 36	48 x 48	-	-
WINDING ROAD	W1-5R(L)	903.6.7	36 x 36	48 x 48	-	-
HAIRPIN CURVE	W1-11R(L)	903.6.7	36 x 36	48 x 48	-	-
COMBINATION HORIZONTAL ALIGNMENT/INTERSECTION	W1-10	903.6.9	36 x 36	48 x 48	-	-
SINGLE ARROW	W1-6	903.6.10	48 x 24	72 x 36	72 x 36	-
CHEVRON	W1-8	903.6.11	18 x 24	30 x 42	30 x 42	-
HILL	W7-1	903.6.13	36 x 36	48 x 48	48 x 48	-
ROAD NARROWS	W5-1	903.6.16	36 x 36	48 x 48	48 x 48	-
NARROW BRIDGE	W5-2	903.6.17	36 x 36	48 x 48	48 x 48	-
ONE LANE BRIDGE	W5-3	903.6.18	36 x 36	48 x 48	48 x 48	-
DIVIDED HIGHWAY CROSSING	W6-1	903.6.19	36 x 36	48 x 48	48 x 48	-
DIVIDED HIGHWAY ENDS	W6-2	903.6.20	36 x 36	48 x 48	48 x 48	-
DOUBLE DOWN ARROW	W12-1	903.6.21	24 x 24	-	-	-
DEAD END	W14-1	903.6.22	36 x 36	36 x 36	36 x 36	-
NO OUTLET	W14-2	903.6.22	36 x 36	36 x 36	36 x 36	-
ROAD ENDS	W14-2A	903.6.22	36 x 36	36 x 36	36 x 36	-
LOW CLEARANCE	W12-2	903.6.23	36 x 36	48 x 48	48 x 48	-
*May be used based on engineering judgment.

Table 903.6.3 Warning Sign Sizes (Sheet 2 of 4)

Sign	Sign Number	Article	Conventional	Expressway (At Grade)	Freeway (Grade Separated)	Other
LOW CLEARANCE (EDUCATIONAL PLAQUE)	W12-2B	903.6.23	24 x 18	24 x 18	24 x 18	-
OVERHEAD LOW CLEARANCE	W12-3	903.6.23	66 x 24 (*72 x 24)	66 x 24 (*72 x 24)	66 x 24 (*72 x 24)	-
BUMP	W8-1	903.6.24	36 x 36	-	-	-
DIP	W8-2	903.6.24	36 x 36	-	-	-
PAVEMENT ENDS	W8-3	903.6.26	36 x 36	-	-	-
SOFT SHOULDER	W8-4	903.6.27	36 x 36	48 x 48	-	-
SLIPPERY WHEN WET	W8-5	903.6.28	36 x 36	48 x 48	-	-
FALLING ROCK	W14-4	903.6.29	36 x 36	48 x 48	48 x 48	-
STOP AHEAD	W3-1A	903.6.31	36 x 36	48 x 48	48 x 48	-
YIELD AHEAD	W3-2A	903.6.31	36 x 36	48 x 48	48 x 48	-
SIGNAL AHEAD	W3-3	903.6.31	36 x 36	48 x 48	48 x 48	-
BE PREPARED TO STOP	W3-4	903.6.31	36 x 36	48 x 48	48 x 48	-
SPEED REDUCTION SIGN	W3-5	903.6.32	36 x 36	48 x 48	48 x 48	-
MERGE	W4-1, W4-5	903.6.33	36 x 36	48 x 48	48 x 48	-
ADDED LANE	W4-3(R/L), W4-6	903.6.34	36 x 36	48 x 48	48 x 48	-
LANE ENDS	W4-2	903.6.35	36 x 36	48 x 48	48 x 48	-
RIGHT (LEFT) LANE ENDS	W9-1R(L)	903.6.35	36 x 36	48 x 48	48 x 48	-
LANE ENDS MERGE LEFT (RIGHT)	W9-2R(L)	903.6.35	36 x 36	48 x 48	48 x 48	-
TWO-WAY TRAFFIC	W6-3	903.6.36	36 x 36	48 x 48	48 x 48	-
NO PASSING ZONE	special	903.6.37	-	-	-	-
EXIT SPEED	W13-2	903.6.38	-	-	48 x 60	-
*May be used based on engineering judgment.

Table 903.6.3 Warning Sign Sizes (Sheet 3 of 4)

Sign	Sign Number	Article	Conventional	Expressway (At Grade)	Freeway (Grade Separated)	Other
RAMP SPEED	W13-3	903.6.38	-	-	48 x 60	-
CROSS ROAD	W2-1	903.6.39	36 x 36	48 x 48	-	-
SIDEROAD: 90 DEGREE	W2-2	903.6.39	36 x 36	48 x 48	-	-
SIDEROAD: 45 DEGREE RIGHT (LEFT)	W2-3R(L)	903.6.39	36 x 36	48 x 48	-	-
T – SYMBOL	W2-4	903.6.39	36 x 36	48 x 48	-	-
Y – SYMBOL	W2-5	903.6.39	36 x 36	48 x 48	-	-
CIRCULAR INTERSECTION	W2-6	903.6.39	36 x 36	48 x 48	-	-
ROUNDABOUT (EDUCATIONAL PLAQUE)	W2-6A	903.6.39	48 x 18	48 x 18	-	-
DOUBLE ARROW	W1-7	903.6.40	48 x 24	72 x 36	72 x 36	-
BICYCLE CROSSING	W11-1	903.6.42	36 x 36	-	-	-
TRUCK CROSSING	W11-10	903.6.42	36 x 36 (*48 x 48)	-	-	-
HORSE DRAWN VEHICLE	W11-14	903.6.42	36 x 36	-	-	-
EMERGENCY VEHICLE	W11-8	903.6.42	48 x 48	-	-	-
HORSE DRAWN VEHICLES	W19-2	903.6.42	36 x 36	-	-	-
PEDESTRIAN CROSSING	W11-2	903.6.43	36 x 36 (*48 x 48)	-	-	-
DEER CROSSING	W11-3	903.6.43	36 x 36	36 x 36	36 x 36	-
CATTLE CROSSING	W11-4	903.6.43	36 x 36	-	-	-
EQUESTRIAN CROSSING	W11-7	903.6.43	36 x 36	-	-	-
PEDESTRIANS ON BRIDGE	W14-6	903.6.43	36 x 36	48 x 48	-	-
FERRY CROSSING _____ FEET	W15-3	903.6.44	36 x 36 (*48 x 48)	-	-	-
*May be used based on engineering judgment.

Table 903.6.3 Warning Sign Sizes (Sheet 4 of 4)

Sign	Sign Number	Article	Conventional	Expressway (At Grade)	Freeway (Grade Separated)	Other
DISTANCE PLAQUES	W16 series, W25-5, W7-3A	903.6.48	varies	varies	varies	-
ADVISORY SPEED	W13-1	903.6.49	24 x 24	30 x 30	30 x 30	-
SUPPLEMENTAL ARROW	W16-7P	903.6.50	30 x 18	30 x 18	30 x 18	-
HILL-RELATED	W7-3(A)	903.6.51	24 x 18	24 x 18	24 x 18	-
ADVANCE STREET NAME	W16-8(A)	903.6.52	var x 12 var x 24	var x 12 var x 24	var x 12 var x 24	-
CROSS TRAFFIC DOES NOT STOP	W4-4	903.6.53	36 x 18	-	-	-
SHARE THE ROAD	W16-1	903.6.54	24 x 30	24 x 30	-	-
PHOTO ENFORCED	W16-10	903.6.56	24 x 18	36 x 24 (*48 x 36)	-	-
IMPASSABLE DURING HIGH WATER	W18-17	903.6.57	36 x 36	-	-	-
GAUGE BOARD	W8-19	903.6.57	9 x 48	-	-	-
HAZARD COMMUNICATION	HCS	903.6.58	-	-	-	24 x 15
BARRICADE	GB4R(L/D)	903.6.59	144 x 72	144 x 72	144 x 75	-
SHOULDER BARRICADES	-	903.6.60	96 x 12	96 x 12	96 x 12	-
TRAVEL SAFE ZONE – FINES DOUBLED	W26-1	903.6.63	36 x 48	48 x 60	48 x 60	-
*May be used based on engineering judgment.

903.6.4 Size of Warning Signs (MUTCD Section 2C.04)

Standard. The sizes for warning signs shall be as shown in Table 903.6.3.

Guidance. The conventional road size should be used on conventional roads.

The freeway and expressway sizes should be used for higher-speed applications to provide larger signs for increased visibility and recognition.

Option. The smaller signs may be used on low-speed roadways where the reduced legend size would be adequate for the warning or where physical conditions preclude the use of the other sizes.

Larger sizes may be used for those special applications where speed, volume or other factors result in conditions where increased emphasis, improved recognition or increased legibility would be desirable.

Signs larger than those shown in Table 903.6.3 may be used with the approval of the State Traffic Engineer. Refer to 903.1.19 for more information.

903.6.5 Sight Distance

Support. The decision to use most warning signs is based on prevailing conditions. The items to be considered when determining the need for a warning sign are sight distance and prevailing speed. Prevailing speed is determined by using either the posted or 85th percentile speed on the facility. Sight distance is the distance a driver requires to perceive, react and respond to a condition. The prevailing speed affects the amount of sight distance required for a condition.

It is a recommended to use Table 903.6.5 to determine the sight distance needed when considering the use of most warning signs. If the sight distance is less than that in Table 903.6.5, a sign may be needed.

Table 903.6.5 Sight Distance Requirments*

Prevailing Speed (mph)	Distance (ft.)
30	200
35	225
40	305
45	360
50	425
55	495
60	570
65	645
70	730
* Based on the AASHTO Green Book, 2001 Edition, Exhibit 3-1

903.6.6 Placement of Warning Signs (MUTCD Section 2C.05)

Support. For information on placement of warning signs, see 903.1.19, 903.2.12 through 903.2.14 and 903.3.

The total time needed to perceive and complete a reaction to a sign is the sum of the times necessary for perception, identification (understanding), emotion (decision making), and volition (execution of decision), and is called the PIEV time. The PIEV time can vary from several seconds for general warning signs to 6 seconds or more for warning signs requiring high road user judgment.

Table 903.6.6 lists suggested sign placement distances for two conditions. This table is provided as an aid for determining warning sign location.

Standard. The minimum visibility for warning signs shall be 175 ft.

Guidance. Warning signs should be placed so that they provide adequate PIEV time. The distances contained in Table 903.6.6 are for guidance purposes and should be applied with engineering judgment. Warning signs are not to be placed so far in advance of the condition that drivers tend to forget the warning because of other driving distractions, especially in urban areas.

Minimum spacing between warning signs with different messages should be based on the estimated PIEV time for driver comprehension of and reaction to the second sign. If an adjustment is necessary, every effort should be made to make it as small as possible.

The effectiveness of the placement of warning signs should be periodically evaluated under both day and night conditions.

Option. The values in Table 903.6.6 can be increased to provide this sign visibility based on field conditions and engineering judgment.

Warning signs that advise road users about conditions that are not related to a specific location, such as Deer Crossing or SOFT SHOULDER, may be installed in an appropriate location, based on engineering judgment, since they are not covered in Table 903.6.6.

Table 903.6.6 Guidelines for Advance Placement of Warning Sign

Posted or 85th Percentile Speed	Advance Placement Distance1
	Condition A: Speed reduction and lane changing in heavy traffic2	Condition B: Deceleration to the listed advisory speed (mph) for the condition4
		03	10	20	30	40	50	60	70
20 mph	225 ft.	N/A5	N/A5	-	-	-	-	-	-
25 mph	325 ft.	N/A5	N/A5	N/A5	-	-	-	-	-
30 mph	450 ft.	N/A5	N/A5	N/A5	-	-	-	-	-
35 mph	550 ft.	N/A5	N/A5	N/A5	N/A5	-	-	-	-
40 mph	650 ft.	125 ft.	N/A5	N/A5	N/A5	-	-	-	-
45 mph	750 ft.	175 ft.	125 ft.	N/A5	N/A5	N/A5	-	-	-
50 mph	850 ft.	250 ft.	200 ft.	150 ft.	100 ft.	N/A5	-	-	-
55 mph	950 ft.	325 ft.	275 ft.	225 ft.	175 ft.	100 ft.	N/A5	-	-
60 mph	1100 ft.	400 ft.	350 ft.	300 ft.	250 ft.	175 ft.	N/A5	-	-
65 mph	1200 ft.	475 ft.	425 ft.	400 ft.	350 ft.	275 ft.	175 ft.	N/A5	-
70 mph	1250 ft.	550 ft.	525 ft.	500 ft.	425 ft.	350 ft.	250 ft.	150 ft.	-
75 mph	1350 ft.	650 ft.	625 ft.	600 ft.	525 ft.	450 ft.	350 ft.	250 ft.	100 ft.
Notes: 1 The distances are adjusted for a sign legibility distance of 175 ft for Condition A. The distances for Condition B have been adjusted for a sign legibility distance of 250 ft, which is appropriate for an alignment warning symbol sign. 2 Typical conditions are locations where the road user must use extra time to adjust speed and change lanes in heavy traffic because of a complex driving situation. Typical signs are Merge and Right Lane Ends. The distances are determined by providing the driver a PIEV time of 14.0 to 14.5 seconds for vehicle maneuvers (2001 AASHTO Policy, Exhibit 3-3, Decision Sight Distance, Avoidance Maneuver E) minus the legibility distance of 175 ft for the appropriate sign. 3 Typical condition is the warning of a potential stop situation. Typical signs are Stop Ahead, Yield Ahead, Signal Ahead, and Intersection Warning signs. The distances are based on the 2001 AASHTO Policy, Stopping Sight Distance, Exhibit 3-1, providing a PIEV time of 2.5 seconds, a deceleration rate of 11.2 ft/second2, minus the sign legibility distance of 175 ft. 4 Typical conditions are locations where the road user must decrease speed to maneuver through the warned condition. Typical signs are Turn, Curve, Reverse Turn, or Reverse Curve. The distance is determined by providing a 2.5 second PIEV time, a vehicle deceleration rate of 10 ft/second2, minus the sign legibility distance of 250 ft. 5 No suggested distances are provided for these speeds, as the placement location is dependent on site conditions and other signing to provide an adequate advance warning for the driver. However, the next lowest deceleration speed could be used.

903.6.7 Horizontal Alignment Signs (W1-1 through W1-5, W1-11) (MUTCD Section 2C.06)

W1-1

W1-2

W1-3

W1-4

W1-5

W1-11

Option. The horizontal alignment Turn (W1-1), Curve (W1-2), Reverse Turn (W1-3), Reverse Curve (W1-4), or Winding Road (W1-5) signs may be used in advance of situations where the horizontal roadway alignment changes. A One-Direction Large Arrow (W1-6) sign may be used on the outside of the turn or curve.

If the change in horizontal alignment is 135 degrees or more or the roadway makes a u-turn, the Hairpin Curve (W1-11) sign may be used. Typically this will be off ramps that are loop ramps. The combination Horizontal Alignment/Intersection sign (W1-10) may be used.

If the difference between the advisory speed and the posted speed is less than 5 mph, the Turn sign may be omitted.

Standard. When engineering judgment determines the need for a horizontal alignment sign, one of the W1-1 through W1-5, or W1-11 signs shall be used.

If used, a turn to the right shall be indicated by a Right Turn (W1-1R) sign or a Reverse Turn Right (W1-3R) sign, while a Left Turn (W1-1L) sign or Reverse Turn Left (W1-3L) sign shall indicate a turn to the left. When a Turn sign is used, additional signing at the turn shall be used, and can be an Arrow Board, Chevrons or a combination of these.

If used, a Curve Right (W1-2R) sign or Reverse Curve Right (W1-4R) sign shall indicate a curve to the right, while the Curve Left (W1-2L) sign or Reverse Curve Left (W1-4L) sign shall indicate a curve to the left.

If used and the first curve/turn is to the right, a Winding Road Right (W1-5R) sign shall be used. If the first curve/turn is to the left, a Winding Road Left (W1-5L) sign shall be used.

The use of the Arrow Board for a Reverse Turn sign shall be the same as for the Turn sign. If used on a combination turn and curve situation, the Arrow Board shall apply only to the turn location.

If the NEXT XX MILES sign (W7-3a) sign is used on a section, the NEXT XX MILES sign, Advisory Speed Plaque, and the Winding Road sign shall be repeated after every intersection with a state route or at one-mile increments.

The Advisory Speed (W13-1) plaque shall be used with all Curve, Turn and Winding Road signs. The plaques shall be mounted on the same post as the warning sign that they modify. The compliance date is December 2009.

The maximum advisory speed posted shall never be more than the posted speed limit. If there is a curve or turn in the section where the difference between the curve/turn appropriate speed and the advisory speed for the winding road section is greater than 15 mph, then the advisory speed for the winding road section shall be used for the Winding Road sign and the curve/turn with the lowest speed shall be signed independently with an advisory speed plaque regardless of the tangent distance. This is done to address driver expectancy and to advise of conditions, which are significantly different.

Guidance. The application of Horizontal Alignment signs should conform to Table 903.6.7.

The Curve signs should be used according to Table 903.6.7 and Figure 903.6.7.1 and when the speed on a curve is more than 5 mph below the posted speed. This sign is also to give notice of hidden or obscure changes in horizontal alignment regardless of the speed limit. If a tangent distance that separates two curves in the same direction is less than 600 ft., the two curves should be signed as one curve. This sign is also to give notice of hidden or obscure changes in horizontal alignment regardless of the speed limit.

If Chevrons are continuously spaced around the turn without a gap, then the Arrow board is not to be used. If, however, there is a gap in the Chevron signing due to an entrance or side road, then the Arrow Board should be used in addition to the Chevrons.

If Winding Road signs are used where the section of winding road extends more than one mile, a supplemental sign, NEXT XX MILES (W7-3a), should be installed below the Advisory Speed Plaque of the Winding Road sign. The appropriate Advisory Speed Plaque to use with the Winding Road sign should be the lowest speed as determined by an engineering study for the whole section. The mileage on the Next XX Miles sign should reflect the number of miles the advisory speed posted is applicable. If the entire length of the winding road has the same advisory speed, the mileage shown on the Next XX Miles sign should indicate the remaining length of the winding road segment (see Figure 903.6.7.2).

Individual curves or turns that require an advisory speed different than the winding road advisory speed should be signed accordingly.

The Hairpin Curve sign should only be used on a loop ramp where the posted exit speed is 30 mph or less.

Table 903.6.7 Horizontal Alignment Sign Usage

Number of Alignment Changes	Advisory Speed
	Less than or equal to 30 mph	Greater than 30 mph
1	Turn (W1-1)1	Curve (W1-2)1
22	Reverse Turn (W1-3)3	Reverse Curve (W1-4)3
3 or more2	Winding Road (W1-5)3
Notes: 1 Engineering judgment should be used to determine whether the Turn or Curve sign should be used. 2 Alignment changes are in opposite directions and are separated by a tangent distance of 600 feet or less. 3 A Right Reverse Turn (W1-3r), Right Reverse Curve (W1-4r), or Right Winding Road (W1-5r) sign is used if the first change in alignment is to the right; a Left Reverse Turn (W1-3L), Left Reverse Curve (W1-4L), or Left Winding Road (W1-5L) sign is used if the first change in alignment is to the left.

Figure 903.6.7.1 Example For Placement of Curve Warning Sign, Condition B: Speed Plaque at 40 and Posted Speed at 50 mph

Figure 903.6.7.2 Winding Road Distance Plaque Application

903.6.8 Combination Horizontal Alignment/Advisory Speed Sign (W1-1a, W1-2a) (MUTCD Section 2C.07)

W1-1a

W1-2a

Option. The Turn (W1-1 sign or the Curve (W1-2) sign may be combined with the Advisory Speed (W13-1) plaque (see 903.6.49) to create a combination Turn/Advisory Speed (W1-1a) sign, or combination Curve/Advisory Speed (W1-2a) sign.

Standard. When used, the combination Horizontal Alignment/Advisory Speed sign shall supplement other advance warning signs and shall be installed at the beginning of the turn or curve.

903.6.9 Combination Horizontal Alignment/Intersection Sign (W1-10) (MUTCD Section 2C.08)

W1-10

Option. The Turn (W1-1) sign or the Curve (W1-2) sign may be combined with the Cross Road (W2-1) sign or the Side Road (W2-2 or W2-3) sign to create a combination Horizontal Alignment/Intersection (W1-10) sign that depicts the condition where an intersection occurs within a turn or curve.

Guidance. Elements of the combination Horizontal Alignment/Intersection sign related to horizontal alignment should conform to 903.6.7, Horizontal Alignment Sign, and elements related to intersection configuration should conform to 903.6.39, Intersection Warning Signs. No more than one Cross Road or two Side Road symbols should be shown on any one combination Horizontal Alignment/Intersection sign.

A layout of the proposed sign should be included when ordering.

Standard. If used, a Curve/Sideroad Left (W1-10L) sign shall indicate a curve to the left, while a Curve/Sideroad Right (W1-10R) sign shall indicate a curve to the right.

Figure 903.6.9 One-Direction Large Arrow Board

903.6.10 One-Direction Large Arrow Sign (W1-6) (MUTCD Section 2C.09)

W1-6

Option. A One-Direction Large Arrow (W1-6) sign may be used to delineate a change in horizontal alignment.

Standard. The One-Direction Large Arrow sign shall be a horizontal rectangle with an arrow pointing to the left or right. If used, the One-Direction Large Arrow sign shall be installed on the outside of a turn or curve in line with and at approximately a right angle to approaching traffic. The One-Direction Large Arrow sign shall not be used where there is no alignment change in the direction of travel, such as at the beginnings and ends of medians or at center piers.

Guidance. The One-Direction Large Arrow sign should be visible for a sufficient distance to provide the road user with adequate time to react to the change in alignment.

If chevrons are used, the One-Direction Large Arrow can replace a chevron. The One-Direction Large Arrow is not to be installed in front of a chevron.

Support. The One-Direction Large Arrow is generally used in conjunction with the Turn sign.

903.6.11 Chevron Alignment Sign (W1-8) (MUTCD Section 2C.10)

W1-8

Option. The Chevron Alignment (W1-8) sign may be used to provide additional emphasis and guidance for a change in horizontal alignment. A Chevron Alignment sign may be used as an alternate or supplement to standard delineators on curves or to the One-Direction Large Arrow (W1-6) sign.

The single-sided Chevron sign side may be used where only one direction of travel is impacted, such as on an expressway.

The double-side Chevron (W1-8D) may be used on two-lane, two-way roads.

Standard. The Chevron Alignment sign shall be a vertical rectangle. No border shall be used on the Chevron Alignment sign. If used, Chevron Alignment signs shall be installed on the outside of a turn or curve, in line with and at approximately a right angle to approaching traffic.

The mounting height of the Chevron sign is 5 ft. above the travel surface. Refer to Figure 903.1.23.1. This will place the sign at approximately the driver’s eye height.

Option. A Chevron Alignment sign may be used on the far side of an intersection to inform drivers of a change of horizontal alignment for through traffic.

Guidance. Space Chevron Alignment signs so that travelers always have at least two in view, until the change in alignment eliminates the need for the signs. Chevron Alignment signs should be visible for a sufficient distance to provide the road user with adequate time to react to the change in alignment.

Table 903.6.11 should be used for determining spacing or refer to the Traffic Studies for Chord Method.

At the end of a divided highway, where the traffic reduces to two lanes, 30 in. x 42 in. chevrons should be used to direct traffic from the dual lanes that are ending and being redirected to the two-lane roadway (see Figure 903.13.22 Standard Signing For Pavement Transition).

Support. Examples of when to use Chevron signs include locations where there is an accident history, evidence of drivers losing control on a curve or turn or a sharp change in alignment not readily visible to the driver.

Table 903.6.11 Chevron Spacing on Curves

Degree of Curve	Radius (ft.)	Spacing on Curve (ft.)	Spacing on Turn (ft.)	Spacing on Tangent (ft.)
	10000	400	200	200
1		304	152	200
	5000	282	141	200
	3000	218	109	196
2		212	106	191
	2500	198	99	178
	2000	176	88	158
3		172	86	155
	1800	168	84	151
	1600	156	78	140
4		148	74	133
	1400	148	74	133
	1200	136	68	122
5		132	66	119
	1000	124	62	112
	900	116	58	104
7		110	55	99
	800	110	55	99
	700	102	51	92
9		96	48	86
	600	94	47	85
	500	84	42	76
12		82	41	74
	400	74	37	67
15		72	36	65
	350	70	35	63
18		66	33	59
	300	64	32	58
21		60	30	54
	250	56	28	50
25		56	28	50
	200	48	24	43
30		48	24	43
	150	40	20	36
40		38	19	34
	100	28	14	25

903.6.12 Truck Rollover Warning Sign (W1-13) (MUTCD Section 2C.11)

W1-13

Option. A Truck Rollover Warning (W1-13) sign may be used to warn drivers of vehicles with a high center of gravity, such as trucks, tankers and recreational vehicles of a curve or turn having geometric conditions that are prone to cause such vehicles to lose control and overturn.

Standard. When the Truck Rollover Warning (W1-13) sign is used, an Advisory Speed Supplemental Plaque (W13-1) plaque indicating the recommended speed for vehicles with a higher center of gravity shall accompany it.

Option. The Truck Rollover Warning sign may be displayed either as a static sign, a static sign supplemented by a flashing warning beacon, or as a changeable message sign activated by the detection of an approaching vehicle with a high center of gravity that is traveling in excess of the recommended speed for the condition.

Support. The curved arrow on the Truck Rollover Warning sign shows the direction of roadway curvature. The truck tips in the opposite direction.

903.6.13 Hill Signs (W7-1) (MUTCD Section 2C.12)

W7-1

W7-1c

Guidance. The Hill (W7-1) sign should be used in advance of a downgrade where the length, percent of grade, horizontal curvature and/or other physical features requires special precautions on the part of road users.

The Hill sign and supplemental grade (W7-3) plaque (refer to 903.6.48) used in combination should be installed in advance of downgrades for the following conditions:

A. 5% grade that is more than 3,000 ft. in length;

B. 6% grade that is more than 2,000 ft. in length;

C. 7% grade that is more than 1,000 ft. in length;

D. 8% grade that is more than 750 ft. in length;

E. 9% grade that is more than 500 ft. in length;

F. 11% grade that is more than 400 ft. in length;

G. 13% grade that is more than 300 ft. in length;

H. 15% grade that is more than 200 ft. in length; or

I. 16% or more grade that is any length.

These signs are also to be installed for steeper grades or where crash experience and field observations indicate a need or at grades of five percent or more where any part of the grade is on a curve sharper than four degrees.

Supplemental plaques (refer to 903.6.46) and larger signs should be used for emphasis or where special hill characteristics exist. On longer grades, the use of the Hill sign with a distance (W7-3a) plaque at periodic intervals of approximately 1 mile spacing should be considered.

Standard. When the percent grade is shown, the GRADE X% (W7-3) plaque shall be placed below the inclined ramp/truck symbol (W7-1).

Support. The Uphill (W7-1c) sign is also available by special request.

903.6.14 Truck Escape Ramp Signs (W7-4 SERIES) (MUTCD Section 2C.13)

Support. Not used in Missouri.

903.6.15 HILL BLOCKS VIEW Sign (W7-6) (MUTCD Section 2C.14)

Support. Not used in Missouri.

903.6.16 ROAD NARROWS Sign (W5-1) (MUTCD Section 2C.15)

W5-1

Guidance. A ROAD NARROWS (W5-1) sign should be used in advance of a transition on two-lane roads where the pavement width is reduced abruptly to such a narrow width that vehicles might not be able to pass without reducing speed.

Option. Additional emphasis may be provided by the use of object markers and delineators. The Advisory Speed (W13-1) plaque may be used to indicate the recommended speed.

903.6.17 NARROW BRIDGE Sign (W5-2) (MUTCD Section 2C.16)

W5-2

Guidance. A NARROW BRIDGE (W5-2) sign should be used in advance of any bridge or culvert having a two-way roadway clearance width of 16 to 18 ft., or any bridge or culvert having a roadway narrower than the width of the approach travel lanes.

Additional emphasis should be provided by the use of object markers, delineators and/or pavement markings.

Option. A NARROW BRIDGE sign may be used in advance of a bridge or culvert on which the approach shoulders are narrowed or eliminated.

903.6.18 ONE LANE BRIDGE Sign (W5-3) (MUTCD Section 2C.17)

W5-3

Guidance. A ONE LANE BRIDGE (W5-3) sign should be used on two-way roadways in advance of any bridge or culvert:

A. Having a clear roadway width of less than 16 ft.; or

B. Having a clear roadway width of less than 18 ft. when commercial vehicles constitute a high proportion of the traffic; or

C. Having a clear roadway width of 18 ft. or less where the sight distance is limited on the approach to the structure.

Additional emphasis should be provided by the use of object markers, delineators and/or pavement markings.

903.6.19 Divided Highway Sign (W6-1, W6-1c) (MUTCD Section 2C.18)

W6-1

W6-1c

Guidance. A Divided Highway (W6-1) symbol sign should be used on the approaches to a section of highway (not an intersection or junction) where the opposing flows of traffic are separated by a median or other physical barrier.

Option. The Divided Highway (W6-1) symbol sign may be accompanied by an educational DIVIDED HIGHWAY supplemental plaque (W6-1c).

Standard. If used, the DIVIDED HIGHWAY supplemental plaque (W6-1c) shall be installed on the same post as the Divided Highway (W6-1) symbol sign.

903.6.20 Divided Highway Ends Sign (W6-2, W6-2c) (MUTCD Section 2C.19)

W6-2

W6-2c

Guidance. A Divided Highway Ends (W6-2) symbol sign should be used in advance of the end of a section of physically divided highway (not an intersection or junction) as a warning of two-way traffic ahead.

Option. The Divided Highway Ends (W6-2) symbol sign may be accompanied by an educational DIVIDED HIGHWAY ENDS supplemental plaque (W6-2c).

Standard. If used, the DIVIDED HIGHWAY ENDS supplemental plaque (W6-2c) shall be installed on the same post as the Divided Highway Ends (W6-2) symbol sign.

903.6.21 Double Arrow Sign (W12-1) (MUTCD Section 2C.20)

W12-1

Option. The Double Arrow (W12-1) sign may be used to advise road users that traffic is permitted to pass on either side of an island, obstruction, or gore in the roadway (see Figure 903.6.21). Traffic separated by this sign may either rejoin or change directions.

Standard. The Double Arrow sign shall not be used in the gores of off ramps on expressways or freeway systems.

Guidance. If used on an island, the Double Arrow sign should be mounted near the approach end. If used in front of a pier or obstruction, the Double Arrow sign should be mounted on the face of, or just in front of, the obstruction. Where stripe markings are used on the obstruction, they should be discontinued to leave a 3 in. space around the outside of the sign.

Figure 903.6.21 Installation For Double Down Arrow Sign

903.6.22 DEAD END/NO OUTLET/ROAD ENDS Signs (W14-1, W14-2, W14- 7) (MUTCD Section 2C.21)

W14-1

W14-2

W14-7

Option. The DEAD END (W14-1) sign may be used at the entrance of a single road or street that terminates in a dead end or cul-de-sac. The NO OUTLET (W14-2) sign may be used at the entrance to a road or road network from which there is no other exit in place of the DEAD END sign.

The ROAD ENDS (W14-7) sign may be used to warn of a roadway which has no outlet and which terminates in a dead end and may be used in place of the DEAD END or NO OUTLET sign where the used of the DEAD END and NO OUTLET signs would have a negative effect on traffic generators or public perceptions due to the negative connotation of the message.

Standard. When the W14-1 or W14-2 sign is used, the sign shall be posted as near as practical to the entry point or at a sufficient advance distance to permit the road user to avoid the dead end or no outlet condition by turning off, if possible, at the nearest intersecting street.

The DEAD END sign shall be placed at the appropriate distance from the end of the roadway based on Table 903.6.6.

The W14-2 or W14-7 sign shall not be used in place of the DEAD END sign at the end of the roadway.

The DEAD END sign shall be installed at the end of any state route that physically ends or ends at a private entrance.

The W14-1, W14-2 or W14-7 sign shall not be used in place of the ROAD CLOSED (R11-2) sign for temporary conditions, such as high water, bridge out, etc.

Guidance. The W14-1, W14-2 or W14-7 sign should be installed just beyond the entrance to all state maintained roadways where this condition exists.

903.6.23 Low Clearance Sign (W12-2, W12-2a AND W12-3) (MUTCD Section 2C.22)

W12-2

W12-2a

W12-2p

Standard. The Low Clearance (W12-2) sign shall be used to warn motorists of clearances of 15 ft. 2 in. or less. The clearance to be indicated on the signs shall be the actual clearance less 2 in. for possible packed snow and ice. All clearance measurements shall be reduced to the nearest lower full inch.

The Low Clearance (W12-2a) plaque shall be used with the Low Clearance sign.

Posting requirements for Low Clearance signs are as follows:

Case I – Two Signs: Where the sign legend for vertical clearance is 15 ft. (15 ft., 2 in. minus 2 in.) or less, but more than 13 ft. 6 in. (13 ft. 8 in. minus 2 in.), two signs shall be used. First, the clearance shall be posted on the structure by an Overhead Low Clearance (W12-2p) sign and, second, a shoulder mounted Low Clearance (W12-2) sign with a Low Clearance (W12-2a) plaque shall be placed about 750 ft. in advance of the structure. When an interchange is involved, the shoulder-mounted Low Clearance (W12-2) sign with a Low Clearance (W12-2b) plaque shall be located about 750 ft. in advance of the off-ramp. The maximum height shown on the signs under these conditions shall be 15 ft. (15 ft., 2 in. measured clearance minus 2 in. for possible paced snow and ice).

Case II – Three signs: Where the sign legend for vertical clearance is 13 ft. 6 in. (13 ft. 8 in. minus 2 in.) or less, three signs shall be used. First, the clearance shall be posted on the structure by a Overhead Low Clearance (W12-2p) sign, second, a shoulder mounted Low Clearance (W12-2) sign with a Low Clearance (W12-2a) plaque shall be placed about 750 ft. in advance of the structure, and third, a second Low Clearance (WW12-2) sign with a Low Clearance (W12-2a) plaque shall be placed at the nearest intersecting road or wide point in the road at which a vehicle can detour or turn around. The maximum height shown on the signs under these conditions shall be 13 ft. 6 in. (13 ft. 8 in. measured clearance minus 2 in. for possible paced snow and ice).

Case III – One Sign: Where the vertical clearance is 15 ft. (15 ft. 2 in. minus 2 in.) or less and where the bridge is state maintained but the road beneath is not, the Overhead Low Clearance (W12-2p) sign shall be mounted on the structure but the shoulder mounted Low Clearance (W12-2) sign shall not be used.

Vertical clearance signing shall be provided for structures within commercial zones (see Missouri Statute 304.190). The legal maximum limit within commercial zones is 16 ft. 0 in. Therefore, we shall warn motorists of vertical clearances of 16 ft. 2 in. or less in commercial zone limits. The clearance to be indicated on the signs shall be the actual clearance less 2 in. The signing for clearances of 16 ft. 2 in. or less within commercial zones shall be the same as Case I and Case III used for signing structures of 15 ft. 0 in. or less.

Guidance. The Overhead Low Clearance (W12-2p) sign should be mounted on a structure centered over the lane or lanes affected.

Where the clearance is less than the legal maximum vehicle height, the W12-2 sign with a supplemental distance plaque (W16-3) should be placed at the nearest intersecting road or wide point in the road at which a vehicle can detour or turn around.

In the case of an arch or other structure under which the clearance varies greatly, two or more signs should be used as necessary on the structure itself to give information as to the clearances over the entire roadway.

Clearances should be evaluated periodically, particularly when resurfacing operations have occurred.

Support. The Overhead Clearance (W12-2p) signs have two parts. The first sign indicates the foot dimensions and the second sign indicates the inch dimension. For example of how to sign for a low clearance of an actual measurement of 13 ft. 6 ¾ in., subtract 2 in. for snow. Therefore, a 13 ft. 4 in. measurement would be shown on the sign.

903.6.24 BUMP and DIP Signs (W8-1, W8-2) (MUTCD Section 2C.23)

W8-1

W8-2

Guidance. BUMP (W8-1) and DIP (W8-2) signs should be used to give warning of a sharp rise or depression in the profile of the road. These signs are only to be used if it is not feasible to eliminate the bump or depression.

A short stretch of depressed alignment that might momentarily hide a vehicle should be treated as a no-passing zone when centerline striping is provided on a two-lane or three-lane road. Refer to No-Passing Zone Pavement Markings and Warrants for more information.

Option. These signs may be supplemented with an Advisory Speed supplemental plaque (W13-1).

Standard. The DIP sign shall not be used at a short stretch of depressed alignment that might momentarily hide a vehicle.

903.6.25 Speed Hump Sign (W17-1) (MUTCD Section 2C.24)

Support. Not used in Missouri.

903.6.26 PAVEMENT ENDS Sign (W8-3) (MUTCD Section 2C.25)

W8-3

Guidance. A PAVEMENT ENDS (W8-3) word message sign should be used where a paved surface changes to either a gravel treated surface or an earth road surface.

903.6.27 SOFT SHOULDER Sign (W8-4) (MUTCD Section 2C.26)

W8-4

Option. The SOFT SHOULDER (W8-4) sign may be used to warn of a soft shoulder condition.

Guidance. Additional shoulder signs should be placed at appropriate intervals along the road where the condition continually exists.

Standard. When used, SOFT SHOULDER sign shall be placed in advance of the condition (see Table 903.6.6).

903.6.28 Slippery When Wet Sign (W8-5) (MUTCD Section 2C.27)

W8-5

Option. The Slippery When Wet (W8-5) sign may be used to warn that a slippery condition might exist.

Guidance. When used, a Slippery When Wet sign should be placed in advance of the beginning of the affected section (see Table 903.6.6) and additional signs should be placed at appropriate intervals along the road where the condition exists.

The Slippery When Wet sign is not to be installed as a final correction. The problem should be fixed and then the sign be removed.

903.6.29 FALLING ROCK Sign (W8-20)

W8-20

Option. The FALLING ROCK (W8-20) sign may be used to warn motorist where falling or fallen rock may be a concern.

903.6.30 BRIDGE ICES BEFORE ROAD Sign (W8-13) (MUTCD Section 2C.28)

Support. Not used in Missouri.

903.6.31 Advance Traffic Control Signs (W3-1, W3-2, W3-3, W3-4) (MUTCD Section 2C.29)

W3-1

W3-2

W3-3

W3-4

Standard. The Advance Traffic Control symbol signs include the Stop Ahead (W3-1), Yield Ahead (W3-2), and Signal Ahead (W3-3) signs. These signs shall be installed on an approach to a primary traffic control device that is not visible for a sufficient distance to permit the road user to respond to the device (see Table 903.6.31 and Figure 903.6.31). The visibility criteria for a traffic control signal shall be based on having a continuous view of at least two signal faces for the distance specified in Table 903.6.31.

Support. Permanent obstructions causing the limited visibility might include roadway alignment or structures. Intermittent obstructions might include foliage or parked vehicles.

Guidance. Where intermittent obstructions occur, engineering judgment should determine the treatment to be implemented.

The minimum visibility distance of a signal for a facility with a speed limit above 60 mph should be determined by summing the stopping sight distance (see Table 903.6.5) and the assumed queue length. The assumed queue length should be determined by engineering judgment.

If an advance traffic control sign is warranted for an approach at an intersection of a MoDOT maintained road and non-MoDOT maintained road, the maintainer of the non-MoDOT road should be notified of the condition.

Option. An Advance Traffic Control sign may be used for additional emphasis of the primary traffic control device, even when the visibility distance to the device is satisfactory. A supplemental street name plaque (refer to 903.6.52) may be installed below an Advance Traffic Control sign.

A warning beacon may be used with an Advance Traffic Control sign.

A BE PREPARED TO STOP (W3-4) sign may be used to warn of stopped traffic caused by a traffic control signal or in advance of a section of roadway that regularly experiences traffic congestion.

Table 903.6.31 Requirements for Signal Ahead Sign Placements

85th Percentile Speed (mph)	Minimum Visibility Distance (ft.)
20	175
25	215
30	270
35	325
40	390
45	460
50	540
55	625
60	715
65	*790
70	*875
* Calculated by summing stopping sight distance (see Table 903.6.5) and assumed queue length of 145 feet, which should be considered minimum.

Figure 903.6.31. Example For Placement of Stop Ahead Sign, Condition B: Posted Speed at 55 mph.

Standard. When a BE PREPARED TO STOP (W3-4) sign is used in advance of a traffic control signal, it shall be used in addition to a Signal Ahead (W3-3) sign.

Option. The BE PREPARED TO STOP (W3-4) sign may be supplemented with a warning beacon.

Guidance. When the warning beacon is interconnected with a traffic control signal or queue detection system, the BE PREPARED TO STOP sign should be supplemented with a WHEN FLASHING (S4-4) plaque.

903.6.32 Speed Reduction Signs (W3-5) (MUTCD Section 2C.30)

W3-5

Standard. A Speed Reduction (W3-5) sign should be used to inform road users of a reduced speed zone when engineering judgment indicates the need for advance notice to comply with the posted speed limit ahead.

Guidance. Speed Reduction signs shall be installed in advance of a speed reduction of 15 mph or greater from the posted speed limit. If used, Speed Reduction signs shall be followed by a Speed Limit (R2-1) sign installed at the beginning of the zone where the speed limit applies.

The speed limit displayed on the Speed Reduction Sign shall be identical to the speed limit displayed on the subsequent Speed Limit sign.

Option. The Speed Reduction sign may also be used on interstates in advance of a 10 mph reduction in speed to provide additional guidance. See Figure 903.13.1 for further details.

903.6.33 Merge Signs (W4-1, W4-5) (MUTCD Section 2C.31)

W4-1

W4-5

Option. A Merge (W4-1) sign may be used to warn road users on the major roadway that merging movements might be encountered in advance of a point where lanes from two separate roadways converge as a single traffic lane and no turning conflict occurs.

An Entering Roadway Merge (W4-5) sign may also be installed on the side of the entering roadway to warn road users on the entering roadway of the merge condition.

Guidance. The Merge sign should be installed on the side of the major roadway where merging traffic will be encountered and in such a position as to not obstruct the road user’s view of entering traffic. Where two roadways of approximately equal importance converge, a Merge sign should be placed on each roadway. The Merge sign is not to be used where two roadways converge and merging movements are not required.

The Merge sign is not to be used in place of a Lane Ends sign where lanes of traffic moving on a single roadway must merge because of a reduction in the actual or usable pavement width. Refer to 903.6.35 for more information.

903.6.34 Added Lane Signs (W4-3, W4-6) (MUTCD Section 2C.32)

W4-3

W4-6

Guidance. The Added Lane (W4-3) sign should be installed in advance of a point where two roadways converge and merging movements are not required. When possible, the Added Lane sign should be placed such that it is visible from both roadways; if this is not possible, an Added Lane sign should be placed on the side of each roadway.

When an Added Lane sign should be installed on a roadway that curves before converging with another roadway that has a tangent alignment at the point of convergence, the Entering Roadway Added Lane (W4-6) sign should be used to better portray the actual geometric conditions to road users on the curving roadway.

903.6.35 LANE END Signs (W4-2, W9-1, W9-2) (MUTCD Section 2C.33)

W4-2

W9-1

W9-2

Guidance. The LANE ENDS MERGE LEFT (RIGHT) (W9-2) word sign, or the Lane Ends (W4-2) symbol sign, which is preferred, should be used to warn of the reduction in the number of traffic lanes in the direction of travel on a multi-lane highway.

Option. The RIGHT (LEFT) LANE ENDS (W9-1) word sign (see Figure 903.13.18) may be used in advance of the Lane Ends (W4-2) symbol sign or the LANE ENDS MERGE LEFT (RIGHT) (W9-2) word sign as additional warning or to emphasize that the traffic lane is ending and that a merging maneuver will be required.

On one-way streets or on divided highways where the width of the median will permit, two Lane Ends (W4-2) signs may be placed facing approaching traffic; one on the right side and the other on the left side or median.

The reduction in the number of traffic lanes may also be delineated with roadway edge lines (see 620.2.9, Lane Reduction Transition Markings) and/or roadway delineation (see 620.4, Delineators).

Guidance. Where an extra lane has been provided for slower moving traffic (see SLOWER TRAFFIC KEEP RIGHT Sign), a Lane Ends word sign or a Lane Ends (W4-2) symbol sign should be installed in advance of the end of the extra lane.

903.6.36 Two-Way Traffic Sign (W6-3, W6-3a, W16-9p) (MUTCD Section 2C.34)

W6-3

W6-3a

W16-9p

Guidance. A Two-Way Traffic (W6-3) sign should be used to warn road users of a transition from a multi-lane divided section of roadway to a two-lane, two-way section of roadway.

A Two-Way Traffic (W6-3) sign with an AHEAD (W16-9p) plaque should be used to warn road users of a transition from a one-way street to a two-lane, two-way section of roadway (see 903.13, Typical Signing Applications).

Option. The Two-Way Traffic sign may be used at intervals along a two-lane, two-way roadway and may be used to supplement the Divided Highway Ends (W6-2) sign discussed in 903.6.20. The Two-Way Traffic (W6-3) sign may be accompanied by an educational TWO WAY TRAFFIC supplemental plaque (W6-3a).

Standard. If used, the TWO WAY TRAFFIC supplemental plaque (W6-3a) shall be installed on the same post as the Two-Way Traffic (W6-3) sign.

903.6.37 NO PASSING ZONE Sign (W14-3) (MUTCD Section 2C.35)

W14-3

Support. The NO PASSING ZONE (W14-3) sign is not to be used on a system-wide basis. It is intended for special use at locations where passing crashes are present and as a measure to correct those accidents.

Standard. The NO PASSING ZONE sign shall be a pennant-shaped isosceles triangle with its longer axis horizontal and pointing to the right. When used, the NO PASSING ZONE sign shall be installed on the left side of the roadway at the beginning of no-passing zones identified by either pavement markings or DO NOT PASS (R4-1) signs or both (see 903.5.25 and the MUTCD 3B.02).

The use of the NO PASSING ZONE sign shall be approved by the State Traffic Engineer.

903.6.38 Advisory Exit and Ramp Speed Signs (W13-2 and W13-3) (MUTCD Section 2C.36)

W13-2

W13-3

Standard. Advisory Exit and Ramp Speed signs shall be vertical rectangles. The advisory Exit Speed (W13-2) shall be used where engineering judgement indicates the need to advise road users of the recommended speed on an exit.

Guidance. When used, the Advisory Exit Speed sign should be installed along the deceleration lane. The Advisory Exit Speed sign should be visible in time for the road user to make a reasonably safe slowing and exiting maneuver.

Option. One or more Advisory Ramp Speed signs may be used along the deceleration lane, beyond the gore, or along the ramp. Based on engineering judgment, the Advisory Ramp Speed sign may be installed on the inside or outside of the curve to enhance its visibility (see Figure 903.6.38). When used, the Advisory Ramp Speed sign should be visible in time for the traveler to reduce to the recommended speed.

A Turn (W1-1) or Curve (W1-2) sign with an Advisory Speed (W13-1) plaque may be used in place of an Advisory Ramp Speed sign if it is located such that it clearly does not apply to drivers on the main roadway.

The advisory speed may be the 85th-percentile speed of free-flowing traffic, the speed corresponding to a 10-degree ball bank indicator reading, or the speed otherwise determined by an engineering study because of unusual circumstances.

Figure 903.6.38 Example of Advisory Speed Signing for an Exit Ramp

903.6.39 Intersection Warning Signs (W2-1 through W2-6) (MUTCD Section 2C.37)

W2-1

W2-2

W2-3

W2-4

W2-5

W2-6

W2-6a

Support. Intersection Warning Signs are used when there is limited sight distance, crashes, or based on engineering judgment.

Option. A Cross Road (W2-1) symbol, Side Road (W2-2 or W2-3) symbol, T-Symbol (W2-4), or Y-Symbol (W2-5) sign may be used in advance of an intersection to indicate the presence of an intersection and the possibility of turning or entering traffic. The Circular Intersection (W2-6) symbol sign accompanied by an educational ROUNDABOUT (W2-6a) plaque may be installed in advance of a circular intersection.

Intersection Warning signs may be used with Advance Traffic Control signs, but not replace the Advance Traffic Control sign.

If other circular intersections exist, that would not be classified a roundabout, the Circular Intersection (W2-6) sign may be used.

The relative importance of the intersecting roadways may be shown by different widths of lines in the symbol.

An advance street name plaque (see 903.6.52) may be installed above or below an Intersection Warning sign.

Standard. The Circular Intersection sign shall be installed in advance of any roundabout intersection. The ROUNDABOUT (W2-6a) plaque along with the appropriate Advisory Speed supplemental plaque (W13-1) shall be installed below the Circular Intersection sign.

Guidance. The Intersection Warning sign should illustrate and depict the general configuration of the intersecting roadway, such as crossroad, side road, T-intersection, or Y-intersection.

The Circular Intersection symbol (W2-6) sign should be installed on the approach to a YIELD sign controlled roundabout intersection.

Where the side roads are not opposite each other, the symbol for the intersection should indicate a slight offset.

Figure 903.6.39 Example of Markings for Roundabout Intersections With One-Lane Approaches

903.6.40 Two-Direction Large Arrow (W1-7) (MUTCD Section 2C.38)

W1-7

Standard. The Two-Direction Large Arrow (W1-7) sign shall be a horizontal rectangle. If used, it shall be installed facing the stem of a T-Intersection or at the fork of Y- Intersections facing the approaching traffic on the far side of the intersection in line with, and at approximately a right angle to, approaching traffic (see Figure 903.6.40).

The Two-Direction Large Arrow sign shall not be used where there is no change in the direction of travel such as at the beginnings and ends of medians or at center piers.

Guidance. The Two-Direction Large Arrow sign should be visible for a sufficient distance to provide the road user with adequate time to react to the intersection configuration.

Figure 903.6.40 Double Arrow Board

903.6.41 Traffic Signal Signs (W25-1, W25-2) (MUTCD Section 2C.39)

W25-1

W25-2

Support. If a left turn trap exists a Traffic Signal sign is needed, unless the signal has a permissive left that is tied to the opposing through (i.e. Dallas phasing).

Standard. Unless a separate left-turn signal face is provided and is operated as described in Section 4D.06 the Federal MUTCD, if the possibility exists that a CIRCULAR YELLOW signal indication could be displayed to an approach from which drivers are turning left permissively without the simultaneous display of a CIRCULAR YELLOW signal indication to the opposing approach (see federal MUTCD section 4D.05), either a W25-1 or a W25-2 sign shall be installed near the left-most signal head. If the operation described in the previous sentence occurs on a cycle-by-cycle basis during all times that the traffic control signal is operated in the stop-and-go mode, the ONCOMING TRAFFIC HAS EXTENDED GREEN (W25-1) sign shall be used; if the operation occurs only occasionally, the ONCOMING TRAFFIC MAY HAVE EXTENDED GREEN (W25-2) sign shall be used.

903.6.42 Vehicular Traffic Signs (W11-1, W11-1a, W11-5, W11-8, W11-10, W11-12p, W11-14) (MUTCD Section 2C.40)

W11-1

W11-1a

W11-5

W11-8

W11-10

W11-12p

W11-14

W16-9p

Option. Vehicular Traffic (W11-1, W11-1a, W11-5, W11-8, W11-10, W11-12p, W11-14) signs may be used to alert travelers users to locations where unexpected entries into the roadway by trucks, bicyclists, farm vehicles, emergency vehicles, horse-drawn vehicles or other vehicles might occur.

The Emergency Vehicle (W11-8) sign may be erected in advance of an unsignalized emergency vehicle entrance. It is primarily used on two-lane highways, but may be used on multi-lane highways in the absence of traffic signals.

Support. These locations may be relatively confined or occur randomly over a roadway segment.

Guidance. Vehicular Traffic signs should be used only at locations where the road user’s sight distance is restricted, or the condition, activity or entering traffic would be unexpected. If the condition or activity is seasonal or temporary, the Vehicular Traffic sign should be removed or covered when the condition or activity does not exist.

For a signal to be eligible for the Emergency Signal Ahead (W11-12p) sign, the emergency station should be visible from the state highway.

Haul routes that are sporadic should use the portable or turnable Truck Crossing installations and have a Contract for Signs at Truck Crossings (TR12), found on p:contract/tr, executed.

When used, the Horse Drawn Vehicles assemblies should be repeated according to the Share the Road sign.

Option. Supplemental plaques (refer to 903.6.46) with legends such as AHEAD (W16-9p), BIKE XING (W11-1a), XX FEET, NEXT XX MILES, or SHARE THE ROAD (W16-1) may be mounted below Vehicular Traffic signs to provide advance notice to road users of unexpected entries.

Standard. The Emergency Vehicle (W11-8) sign with the EMERGENCY SIGNAL AHEAD (W11-12p) supplemental plaque shall be placed in advance of all emergency-vehicle traffic control signals.

903.6.43 Nonvehicular Sign (W11-2, W11-3, W11-4, W11-7, W11-8, W11-19, W16-9p6) (MUTCD Section 2C.41)

W11-2

W11-3

W11-4

W11-7

W11-18

W11-19

W16-9p

Option. Nonvehicular signs may be used to alert road users in advance of locations where unexpected entries into the roadway or shared use of the roadway by pedestrians, animals and other crossing activities might occur.

Support. The conflicts may be relatively confined or occur randomly over a roadway segment.

Standard. The Pedestrian (W11-2) sign shall be used in advance of a marked pedestrian crossing. At a marked pedestrian crossing the Pedestrian sign and the Diagonal Downward Crossing Arrow (W16-7p) plaque shall be used, except at signalized and stop controlled intersections.

The Cattle (W11-4) sign shall be issued to an individual only when the Application for Sign at Cattle Crossings contract (TR9), found on P:/contract/tr, has been signed.

When used at the crossing, Nonvehicular signs, excluding Deer (W11-3) signs, shall be supplemented with a diagonal downward pointing arrow (W16-7p) plaque showing the location of the crossing.

Guidance. Deer signs put up due to temporary flooding or development should be reevaluated when the condition stabilizes.

The district traffic engineering staff is to confirm the need for the Equestrian (W11-7) sign.

Option. When used in advance of a crossing, Nonvehicular warning signs may be supplemented with supplemental plaques (903.6.46) with the legend AHEAD, XX FEET, NEXT XX MILES or SHARE THE ROAD to provide advance notice to road users of crossing activity.

The crossing location may be defined with crosswalk markings (see 620, Pavement Markings).

School signs and their related supplemental plaques may have a fluorescent yellow-green background with a black legend and border.

Guidance. When a fluorescent yellow-green background is used, a systematic approach featuring one background color within a zone or area should be used. The mixing of standard yellow and fluorescent yellow-green backgrounds within a selected site area should be avoided.

Nonvehicular signs should be used only at locations where the crossing activity is unexpected or at locations not readily apparent.

903.6.44 FERRY CROSSING XXX FEET Sign (W3-10)

W3-10

Option. The FERRY CROSSING XXX FEET (W3-10) sign may be erected for a ferry crossing. A STOP (R1-1) sign at the ferry crossing may be used as a supplement.

903.6.45 PLAYGROUND Sign (W15-1) (MUTCD Section 2C.42)

Support. Not used in Missouri.

903.6.46 Use of Supplemental Plaques (MUTCD Section 2C.43)

Option. A supplemental plaque may be displayed with a warning sign when engineering judgment indicates that road users require additional information beyond that contained in the main message of the warning sign.

Standard. Supplemental plaques shall be used only in combination with warning or regulatory signs. They shall not be mounted alone or displayed alone. If used, a supplemental plaque shall be installed on the same post(s) as the warning sign.

903.6.47 Design of Supplemental Plaques (MUTCD Section 2C.44)

Standard. A supplemental plaque shall have the same color legend, border, and background as the warning sign with which it is displayed. Supplemental plaques shall be square or rectangular.

903.6.48 Distance Supplemental Plaques (W16-2 SERIES, W16-3 SERIES, W25-5, W16-4, W7-3a) (MUTCD Section 2C.45)

W16-2

W16-3

W16-4

W7-3a

Option. The Distance Ahead (W16-2 series and W16-3 series) supplemental plaques may be used to inform the road user of the distance to the condition indicated by the warning sign.

The Next Distance (W7-3a and W16-4) supplemental plaques may be used to inform road users of the length of roadway over which the condition indicated by the warning sign exists.

Standard. Distances shall be shown in ¼-mile or 100-ft. increments. If the distance is less than a ½-mile then feet shall be used.

903.6.49 Advisory Speed Supplemental Plaque (W13-1) (MUTCD Section 2C.46)

W13-1

Option. The Advisory Speed (W13-1) plaque may be used to supplement any warning sign to indicate the advisory speed for a condition.

The Advisory Speed supplemental plaque may be used in conjunction with any standard warning sign.

Standard. The Advisory Speed supplemental plaque shall be used with all curve, turn and winding road signs and where an engineering study (ballbanking) indicates a need to advise road users of the advisory speed for a condition. If used, the Advisory Speed supplemental plaque shall carry the message XX MPH. The speed shown shall be a multiple of 5 mph.

Engineering Study for Ballbanking

Except in emergencies or when the condition is temporary, an Advisory Speed supplemental plaque shall not be installed until the advisory speed has been determined by an engineering study. Advisory Speed supplemental plaques shall never be mounted alone. The maximum advisory speed posted shall never be more than the posted speed limit.

Guidance. Because changes in conditions, such as roadway geometrics, surface characteristics, or sight distance, might affect the advisory speed, each location should be periodically evaluated and the Advisory Speed plaque changed if necessary.

Option. The advisory speed may be the 85th-percentile speed of free-flowing traffic, the speed corresponding to a 10-degree ball bank indicator reading, or the speed otherwise determined by an engineering study because of unusual circumstances.

Support. The Advisory Speed supplemental plaques are available in 5 mph increments.

903.6.50 Supplemental Arrow Plaque (W16-7pL, W16-7pR) (MUTCD Section 2C.47)

W16-7pL

W16-7pR

Guidance. If the condition indicated by a warning sign is located on an intersecting road and the distance between the intersection and condition is not sufficient to provide adequate advance placement of the warning sign, a Supplemental Arrow (W16-7pL and W16-7pR) plaque should be used below the warning sign.

Standard. Supplemental Arrow plaques shall have the same legend design as the Advance Turn Arrow and Directional Arrow auxiliary signs except that they shall have a black legend and border on a yellow or fluorescent yellow-green background, as appropriate.

903.6.51 Hill-Related Supplemental Plaques (W7-3 Series) (MUTCD Section 2C.48)

W7-3

W7-3a

Guidance. Hill-Related (W7-3 series) supplemental plaques or other appropriate legends and larger signs should be used for emphasis or where special hill characteristics exist. On longer grades, the use of the supplemental distance plaque (W7-3a) at periodic intervals of approximately 1 mile spacing should be considered.

903.6.52 Advance Street Name Supplemental Plaque (W16-8, W16-8a) (MUTCD Section 2C.49)

W16-8

W16-8a

Support. Advance street name signing can provide valuable information to the motorist. Intersections that are signed with Intersection Warning (W2 series) or Advance Traffic Control (W3 series) signs typically have inherent sight distance concerns. The addition of the street name to the warning sign can aid a motorist in making decisions in a timely manner.

Option. An Advance Street Name (W16-8 or W16-8a) suplemental plaque may be used with any Intersection sign (W2 series) or Advance Traffic Control (W3 series) sign to identify the name of the intersecting street.

If the side road being signed is maintained by a public agency, the addition of the street name sign may be considered on request.

Guidance. Advance Street Name supplemental signs are only to be used with intersection or advance traffic control warning signs that are properly installed according to MoDOT guidelines.

Standard. The street name used on an Advance Street Name supplemental sign shall be the approved name used by either the local agency or the Emergency 911 Coordinator.

When used, the Advance Street Name supplemental plaque shall only be mounted below the W2 or W3 series warning sign or the Mileage Plaque on the same post. The Advance Street Name supplemental plaque for a 36 in. x 36 in. warning sign shall be a maximum of 36 in. wide and for a 48 in. x 48 in. warning sign shall be a maximum of 48 in. wide.

903.6.53 CROSS TRAFFIC DOES NOT STOP Suppplemental Plaque (W4-4) (MUTCD Section 2C.50)

W4-4

Option. The CROSS TRAFFIC DOES NOT STOP (W4-4) supplemental plaque may be used in combination with a STOP sign when engineering judgment indicates that conditions are present that are causing or could cause drivers to misinterpret the intersection as an all-way stop.

Standard. If the W4-4 plaque is used, it shall be installed below the STOP sign.

903.6.54 SHARE THE ROAD Supplemental Plaque (W16-1) (MUTCD Section 2C.51)

W16-1

Option. In situations where there is a need to warn drivers to watch for other slower forms of transportation traveling along the highway, such as bicycles or horse-drawn vehicles, a SHARE THE ROAD (W16-1) supplemental plaque may be used.

903.6.55 HIGH OCCUPANCY VEHICLE (HOV) Supplemental Plaque (W16-11) (MUTCD Section 2C.52)

Support. Not used in Missouri.

903.6.56 PHOTO ENFORCED Supplemental Plaque (W16-10) (MUTCD Section 2C.53)

W16-10

Option. A PHOTO ENFORCED (W16-10) supplemental plaque may be mounted below a warning sign to advise road users that the regulations associated with the condition being warned about (such as a traffic control signal) are being enforced by photographic equipment.

Standard. If used below a warning sign, the PHOTO ENFORCED supplemental plaque shall be a rectangle with a black legend and border on a yellow background.

903.6.57 IMPASSABLE DURING HIGH WATER Sign (W8-16, W8-17, W8-18, W8-19)

W8-16

W8-17

W8-18

W8-19

Option. The IMPASSABLE DURING HIGH WATER (W18-17) sign may be used to warn of low water crossing, or section of highway where normal rainfall will cause water to be over the roadway, see the Traffic Control For Field Operations Manual. Where used, this sign may be a flip sign with the combination of a WATER OVER ROAD sign (W8-16). Refer to Traffic Control for Field Operations.

The LOW WATER CROSSING (W8-18) may also be used to warn of low water crossings.

Standard. The Gauge Board (W8-19) sign shall be used at all low water crossings as a supplement to the IMPASSABLE DURING HIGH WATER sign.

903.6.58 Hazard Communication Signs

Hazard Sign

Support. Missouri's Community Right-to-Know law requires visible markings on the outside of buildings, rooms and containers where hazardous substances are present.

The NFPA 704 marking system uses a diamond-shaped sign (Exhibit D) that is divided into four smaller diamonds. The four smaller diamonds, which are 7½ in. square, are different colors (blue, red, yellow and white) with numbers or symbols that represent the hazards posed by the materials stored inside the building or room. The four quadrants of the sign indicate the potential hazards associated with health (blue), fire or flammability (red), reactivity (yellow) and special hazards (white). Special hazards (white) will not be indicated on our signing.

To verify correct marking contact the district safety officer or the Environmental Compliance Coordinator.

Standard. Hazard Communication signs shall conform to the National Fire Protection Association (NFPA) standard 704, except that containers may be marked to conform to the OSHA hazard communication standard.

Each highway facility where reportable quantities of hazardous materials are used or stored shall be visibly marked with a diamond-shaped sign conforming to the NFPA standard 704 marking system. The sign shall be mounted on the outside wall of each building or room next to the pedestrian door. If the pedestrian door is located on the end of the building, a second sign shall be mounted on the front outside wall near the center of the building.

Bulk striping paint storage docks and/or aboveground storage tanks shall be marked with a sign. Aboveground paint storage tanks shall have a sign (decal) mounted near the top of the tank on the side facing the drive or lot. A post-mounted sign shall be located at the front of paint storage docks in a spot, which is highly visible but not where it will interfere with the loading or unloading of paint.

Aboveground asphalt storage tanks shall have a sign (decal) mounted near the top of the tank on the end or side facing the drive or lot. If there is more than one tank at a single location, only one tank has to be marked with a sign.

Guidance. It may be necessary to periodically change the numbers on signs to conform to current storage conditions. Any changes to the signs should be made within two weeks after current storage conditions change.

Table 903.6.58 Hazardous Material Sign Information

Number	FMS	Legend	Other
HCS-10	8010125005	HAZ COM BLANK ALUM P	15 X 15
HCS-B0	8010125015	HAZ COM BLU #0 6/SHT	24 X 15
HCS-B1	8010125020	HAZ COM BLU #1 6/SHT	24 X 15
HCS-B2	8010125025	HAZ COM BLU #2 6/SHT	24 X 15
HCS-B3	8010125030	HAZ COM BLU #3 6/SHT	24 X 15
HCS-B4	8010125035	HAZ COM BLU #4 6/SHT	24 X 15
HCS-R0	8010125040	HAZ COM RED #0 8/SHT	30 X 15
HCS-R1	8010125045	HAZ COM RED #1 8/SHT	30 X 15
HCS-R2	8010125050	HAZ COM RED #2 8/SHT	30 X 15
HCS-R3	8010125055	HAZ COM RED #3 8/SHT	30 X 15
HCS-R4	8010125060	HAZ COM RED #4 8/SHT	30 X 15
HCS-20	8010125010	HAZ COM WHT NRFL SHT	15 X 15
HCS-Y0	8010125065	HAZ COM YEL #0 8/SHT	30 X 15
HCS-Y1	8010125070	HAZ COM YEL #1 8/SHT	30 X 15
HCS-Y2	8010125075	HAZ COM YEL #2 8/SHT	30 X 15
HCS-Y3	8010125080	HAZ COM YEL #3 8/SHT	30 X 15
HCS-Y4	8010125085	HAZ COM YEL #4 8/SHT	30 X 15

903.6.59 Sign Barricades (GB4 Series)

GB-4E

GB-4R

GB-4L

GB-4D

Option. Sign Barricades (GB-4L or GB-4R) may be used when added emphasis is needed for a change in horizontal roadway alignment. (see Figure 903.6.59.1).

Sign Barricades (GB-4D) may be used opposite the stem of the tee intersection (see Figure 903.6.59.2).

Guidance. The GB-4 Series barricades should be centered with the approaching lane of traffic. GB-4 Series signs should not be used at transitions from 4 lane divided to 2 lane roadways (seeFigure 903.13.22, Standard Signing for a Pavement Transition) for typical signing at these locations.

Standard. Sign Barricades (GB-4 Series) shall be installed per MoDOT Standard Plan 903.02.

GB-4D barricades shall be placed on the far side of the T-intersection with the lines sloping downward in both directions from the center of the barricade.

GB-4R barricades shall be placed in the line of site of the driver approaching the left turn with the stripes sloping downward from the right to the left.

GB-4L barricades shall be placed in the line of site of the driver approaching the right turn with the stripes sloping downward from the left to the right.

GB-4E barricade shall be placed where roadways end and no vehicular movements are provided, the stripes shall slope downward toward the center of the barricade.

Figure 903.6.59.1 Right and Left Barricade Boards

Figure 903.6.59.2 Barricade Board

903.6.60 Shoulder Barricade Assembly

GB-1

Option. Shoulder barricades may be used for added emphasis of standard warning sign installations at the direction of the engineer.

Standard. The shoulder barricade assembly shall consist of three horizontal boards (GB-1L (R)) marked with reflective diagonal stripes and a 48” standard warning sign. See Figure 903.6.60 for typical construction.

GB-1R shoulder barricades shall be installed on the right side of the travelway and have diagonal stripes sloping downward from the right to the left.

GB-1L shoulder barricades shall be installed on the left side of the travelway and have diagonal stripes sloping downward from the left to the right.

Option. Supplemental signs may be installed on the shoulder barricade at the direction of the engineer.

Guidance. Shoulder Barricades should be installed on the appropriate sized wood post or on wide flanged structural steel posts.

Figure 903.6.60 Shoulder Barricade Assembly

903.6.61 Warning Signs Provided for Other Agencies

Support. MoDOT will provide, if requested by the appropriate local traffic authority, warning signs for conditions beyond the end of our right of way.

If the location for placement of an advance warning sign for a curve, turn, paved road, stop condition or other condition deemed appropriate falls on our right of way, MoDOT will place and maintain the traffic control device on MoDOT right of way at the request of the local traffic authority.

Standard. The placement of all traffic control devices on the state highway system shall be governed by the Engineering Policy Guide. MoDOT is responsible for the placement and maintenance of all signs on our right of way.

903.6.62 Passing Lanes (W4-10, W4-11, W4-12, W4-12a)

W4-10

W4-11

W4-12

W4-12a

Support. Alternating passing lanes may be provided on rural, two-lane highways to provide motorists with an opportunity to pass slower vehicles without crossing the centerline. Where passing lanes are provided, operations and safety may be improved by giving motorists advance information about the location of passing lanes. Providing motorists with advance notice of passing lanes may reduce the number of passing maneuvers.

Standard. The PASSING LANE ENDS (W4-10), WATCH FOR LEFT-TURNING TRAFFIC IN PASSING LANE (W4-11), PASSING LANE SYMBOL (W4-12) and PASSING LANE PLAQUE (W4-12a) signs shall be black legend and yellow background and shall only be used in alternating passing lane sections.

The PASSING LANE ENDS sign shall be used prior to the end of the passing lane to warn motorists the passing lane in that direction of travel is ending and merging back to a single lane. The sign shall be placed in advance of the LANE ENDS MERGE RIGHT (W9-2R) sign a distance determined by Table 903.6.6 Guidelines for Advance Placement of Warning Sign.

The PASSING LANE SYMBOL sign shall be placed at the beginning of each passing lane to indicate a passing lane is now available. The sign shall be oriented so that the arrows on the sign correspond to the actual lane configurations. The PASSING LANE PLAQUE (W4-12a) shall be used above the PASSING LANE SYMBOL. The supplemental distance plaque (W7-3a) shall be used below the PASSING LANE PLAQUE. Refer to Figure 903.13.24 Typical Signing for Passing Lanes.

Option. The WATCH FOR LEFT TURNING TRAFFIC IN PASSING LANE sign may be used at locations in a passing lane segment where left turns are common, such as at a county road. This sign may be installed at the judgement of the engineer.

903.6.63 TRAVEL SAFE ZONE – FINES DOUBLED Sign (W26-1)

W26-1

Support: The TRAVEL SAFE ZONE (W26-1) sign is not to be used on a system-wide basis. It is intended for special use at locations where severe crashes are occurring. There is a requirement for regional support to focus a safety campaign involving local law enforcement and public information efforts to reduce the number and severity of crashes within the travel safe zone.

Standard: A TRAVEL SAFE ZONE – FINES DOUBLED sign shall be used to mark the beginning of a designated travel safe zone. This sign is installed in conjunction with the FINES DOUBLED ENDS (R2-20) sign.