# Presentation: 307271

## MUTCD Part 4: Traffic Signals

**Notes:**
We now move on to Part 4 of the new Manual.  Traffic signals are addressed in Part 4.

## Changes in General

- defined all terms in text:  71 definitions versus 4 previously
- deleted definitions no longer appearing in text

**Changes in General**

**Notes:**
71 Definitions associated with signal applications have been added to Part 4.  The definitions in Part 4 are distinct from the definitions apply to terms used specifically for signal operations.  Example:  Conflict Monitor and Controller Unit.

Instead of talking about reformatting, I suggest that we cover “definitions” since it appears in slide above.

## Part 4 is Reorganized for Clarity

- New technology items added in new chapter 4F through 4L
- old 4E now six individual chapters
- new 4E is.....
- reason:......
- Symbols required for all new pedestrian signals

**Notes:**
We reorganized part 4 for clarity. 

Chapter 4E in the ‘88 edition was titled “Other Highway Traffic Signals.” It contained sections on the hazard identification beacons, intersection control beacons, stop sign beacons, etc. The new Chapter 4E in the 2000 MUTCD is titled “Pedestrian Control Features” and addresses typical pedestrian signal indicators. The new Chapter 4K in the 2000 MUTCD covers the types of flashing beacons.

Chapter 4E in the ‘88 edition also contained sections on: Lane Use Control Signals ( New Chapter 4J in the 2000 MUTCD), Traffic Control for Moveable Bridges (New Chapter 4I in the 2000 MUTCD), Traffic Control Signals for Emergency Vehicle Access ( New Chapter 4F in the 2000 MUTCD), and Traffic Control Signals for Freeway Entrance Ramps (New Chapter 4H in the 2000 MUTCD).

## Slide 4

**Notes:**
New technology can be confusing to the user.  Part 4 on Traffic Signals in the 2000 Manual attempts to clarify and present information with the road users in mind.

## Important Notes 

- RED ARROWs are allowed in the 2000 manual (chapter 4D)
- 11 warrants consolidated into eight warrants (chapter 4C)
- warrants 1, 2, & 8 combined into warrant 1
- eight-hour vehicular volume
- warrant 10 (peak hour) and warrant 11 (peak hour) volume now warrant 3: peak hour

**Notes:**
RED ARROWS were allowed in the 1988 Manual and are retained in the 2000 Manual, even though the FHWA had proposed to delete RED ARROWS in a notice of proposed rule making.  There was overwhelming support for keeping the RED ARROWS. 

The number and complexity of Warrants was modified for the 2000 Manual by consolidating some of them together.  Warrants 1, 2, & 8 were combined into Warrant 1 on eight hour vehicular volume

## Important Notes (cont’d) 

- WARRANT 10  (Peak Hour Delay) and WARRANT 11 (Peak Hour Volume) are now consolidated into WARRANT 3

**Notes:**
In the 1988 edition, Warrant 10 addressed “Peak Hour Delay” and Warrant 11 addressed “Peak Hour Volumes.” In the 2000 edition these were consolidated into Warrant 3. The peak hour warrant is intended for use at locations where traffic conditions are such that for a minimum of 1 hour of an average day, the minor street traffic suffers undue delay when entering or crossing the major street.

## Important Notes (cont’d)

- Traffic control signal needs studies:  warrant 1, eight-hour vehicular volume (chapter 4C)
- elimination of the “56% rule”
- values for 80% and 70% are added to table 4C-1

**Notes:**
In the 1988 manual, where speeds were greater than 40 mph  or population was less than 10,000, only 70% of Warrants 1 & 2 had to be met.  Combination Warrant 8 was met when 80% of Warrants 1 and 2 were satisfied.  This was the 56% assumption.

The Warrant 8, allowing for 80% of the minimum vehicular volume and interruption of continuous traffic values, has been incorporated into Warrant 1 shown on Table 4C-1 which is the next slide. 

## Table 4C-1:  Warrants

**Table 4C-1:  Warrants**

**Notes:**
The 56% assumption is eliminated because the values for 80% and 70% are listed separately.

This was done because 80% of the minimum vehicular volume and interruption of continuous traffic values was what was originally intended, but some practitioners were calculating 80% of the 70% value.  Table 4C-1 shows how the new Warrant 1 is applied.

## Change in Standards

- Meaning of vehicular signal indications** **
- STANDARD:  new language added to allow turns on CIRCULAR RED from a ONE-WAY street onto a ONE-WAY street
- STANDARD: new language added to prohibit turns on RED ARROW, except when a sign is used to indicate turns are allowed on red after stopping

**Notes:**
In the 1988 Manual, Section 4B-5 of the 1988 MUTCD, did not allow turns on CIRCULAR RED nor RED ARROW.  In the 2000 Manual, Standard language was added to Section 4D to allow turns on CIRCULAR RED from a one-way street into a one-way street.

Standard language is also added to prohibit turns on RED ARROWS except when a sign is used to indicate that turns are allowed on red after stopping.

## Change in Standards (cont’d)

- Temporary traffic control signals (4D.20)
- STANDARD: defines temporary versus portable traffic control signals
- Section greatly expanded with standards, guidance, and support information

**Notes:**
“Temporary” and “portable” traffic control signals have been redefined to have fewer restrictions on their use. 

Temporary is defined as being installed for a limited time period

Portable is defined as a temporary signal designed to be transported and reused at different locations

## Size, Design, and Illumination of Pedestrian Signal Indications (4E.04)
STANDARD:  All new pedestrian signals shall consist of symbolized messages

- Size, Design, and Illumination of Pedestrian Signal Indications (4E.04)
- STANDARD:  All new pedestrian signals shall consist of symbolized messages

**Notes:**
Pedestrian signal indication requirements have been revised for recognition and adequate visibility. The reason for this is that research has found that the 6 in. pedestrian symbols, are adequate for distances of up to 100 ft.  The subjects used in the research included 48 seniors aged 62 and older.  The research included incandescent light emitting diode (LED) and fiber-optic pedestrian signals.

## Change in Standards (cont’d)

- Traffic control signals for one-lane, two-way facilities (chapter 4G)
- revised and expanded to include provisions for the application, design, and operation of these type of facilities

**Notes:**
In the 1988 edition, traffic control signals for One lane., Two Way facilities was covered in one paragraph (see Section 4E-24 of 1988 Edition)  The 2000 MUTCD has expanded the information into a new Chapter 4G which contains provisions for the application, design and operation of these type of facilities. 

An example of the new information covered is:
Special signal that assigns right-of-way to vehicles; flashing red light
Includes one-lane bridges, tunnels, or temporary traffic control zones.

## Change in Standards (cont’d)

- Design of freeway entrance ramp control signals (4H.02)** **
- Eliminates “8 in diameter lens” requirement
- Eliminates the requirement to place a signal face on the left and right side of entrance ramps
- GUIDANCE changed to OPTION that the mounting height may be between 4.5 and 6 feet

**Notes:**
In section 4H.02 titled “Design Of Freeway Entrance Ramp Control,” the following items which used to be in the 1988 edition are deleted in the 2000 edition.
The requirement to place a ramp signal on the left and right side of the entrance ramp; and
The requirement that ramp control signals must use 8 inch diameter lenses.

The following guidance which used to be in the 1988 edition is changed to OPTION in the 2000 edition:
The ramp signal face may be mounted between 4 1/2 ft. and 6 ft. above the pavement grade.

## Change in Standards (cont’d)

- Meaning of lane-use control signal indications (4J.02)
- STANDARD: provides definitions for lane-use signal indications; specifically:
- WHITE TWO-WAY LEFT-TURN ARROW
- WHITE ONE-WAY LEFT-TURN ARROW

**Notes:**
The following new standards for lane-use control signal indications are added:

In Paragraph C. A steady WHITE TWO-WAY LEFT-TURN ARROW signal indication (see Figure 4J-1) shall mean that a road user is permitted to use the specified lane for a left turn, but not for through travel. The road user needs to understand that the lane is also used by other oncoming road users who are making opposing left turns.

In Paragraph D. A steady WHITE ONE WAY LEFT-TURN ARROW signal indication (see Figure 4J-1) shall mean that a road user is permitted to use a lane over which the signal indication is located for a left turn (without opposing turns in the same lane), but not for through travel.”

## Change in Standards (cont’d)

- Design of lane-use control signals** **(4J.03)
- STANDARD: the nominal minimum height and width of each
- STANDARD: downward green arrow, yellow X and red X shall be 18 inches instead of 12 inches
- OPTION:  allows for use of 300 mm (12 inches) signal faces in areas with minimal visual clutter and speeds equal to or less than 70 km/h (45 mph)

**Notes:**
For Design of Lane-Use Control Signals, the nominal minimum height and width of each DOWNWARD GREEN ARROW, YELLOW X, and RED X signal face shall be 450 mm (18 inches) instead of 12 inches.The FHWA believes this change will ensure that these critical signals are adequately conspicuous to capture the driver’s attention.  

As an option: In areas with minimal visual clutter and with speeds of 70 km/h (45 mph) or less, lane-use control signal faces with minimum height and width of 300 mm (12 in) may be used for the DOWNWARD GREEN ARROW, YELLOW X, and RED X signal faces.”

## Change in Standards (cont’d)

- Speed limit sign beacon** **(4K.04)
- STANDARD:  shall consist of one or more signal sections with a flashing CIRCULAR YELLOW signal indication that has a nominal diameter of not less than 200 mm (8 inches)

**Notes:**
In section 4K.04, the nominal minimum diameter for a Speed Limit Sign Beacon shall consist of one or more signal sections of a standard traffic control signal face, with a flashing CIRCULAR YELLOW signal indication in each signal section. The signal lenses shall have a nominal diameter of not less than 200 mm (8 in).”

The 1988 text stated two CIRCULAR YELLOW lens sections each having a visible diameter of not less than 6 inches has been superceded.

## New Standards

- Application of steady signal indications for left turns**  **
- STANDARD added to allow shared left turn signal face for protected / permissive mode (also known as Dallas left turn phasing)

**Notes:**
New standard language has been added to allow a shared left-turn signal face for protected/permissive mode, which is also known as Dallas left-turn phasing.  The shared left-turn signal face has 5 sections.  During the protected left-turn movement, the signal face shall simultaneously display a left turn GREEN ARROW and a circular GREEN for the adjacent through lane. During the protected left-turn movement, the signal face for through traffic on the opposing approach shall simultaneously display CIRCULAR RED.  During the permissive left-turn movement, all signal faces on the approach shall display CIRCULAR GREEN.

## Maximum Mounting Height of Signal Faces

- Based on a 20 degree viewing angle

**Notes:**
A vertical viewing angle of as high as 23.8 degrees was implicitly allowed in the 1988 MUTCD.  Ergonomic statistics demonstrated that, with these extreme vertical angle placements, tall motorists are unable to view the top of the signal face because they are blocked by the vehicle ceiling line.  Therefore, the FHWA changed the maximum height of a signal head to fall in line with a 20 degree maximum vertical viewing angle.

This graph shows the different maximum mounting heights allowed depending on how far the signals are from the stop line.

The top of the signal housing shall not be more than 25.6 ft (7.8m) above the pavement.

## New Standards (cont’d)

- In-roadway lights (chapter 4L)
- added a new chapter to provide standards, guidance, options, and support for the design and operation of in-roadway lights installations.
- STANDARD:
- installation only at uncontrolled, marked crosswalks with applicable warning signs
- parallel to the edge of the crosswalk
- operation to be initiated based on pedestrian actuation
- operations to cease at predetermined time
- height of the lights not to exceed 20mm (3/4 inch)

**Notes:**
In-Roadway Lights warn road users that they are approaching a condition on or adjacent to the roadway that might not be readily apparent and might require the road users to slow down and possibly come to a stop.  These conditions include, but are not limited to, marked crosswalks that are not controlled by STOP signs, YIELD signs, or traffic control signals. 

## In-Roadway Warning Lights

**Notes:**
This figure is an example of In-Roadway Lights.  This new chapter has been added to the 2000 MUTCD to provide Standards, Guidance, Options, and Support for the design and operation of In-Roadway Lights installations.

Some of the STANDARDs are:
Installation shall occur only at uncontrolled, marked crosswalks with applicable warning signs
Parallel to the edge of the crosswalk
Operation shall be initiated based on pedestrian actuation
Operations shall cease at a predetermined time or with passive detection when the pedestrian clears the cross walk
The height of the lights shall not exceed 20 mm or 3⁄4 inch.

## Accessible Pedestrian Signals and Detectors

**New Accessible Pedestrian Signal Detector**

**Notes:**
The vast majority of intersections will not require any accessible pedestrian signals.  However, for those intersections that do present difficulties for pedestrians who have visual disabilities to cross safely and effectively, the intersection should first be reviewed for pedestrian safety in general (both visually able and visually disabled pedestrians) and then a further examination to assess whether accessible signals would provide information not readily apparent in the environment.

Consideration of these devices is important because many factors increase crossing difficulty.  These include:

Increasingly quiet cars
Right turn on red, which masks the beginning of the through phase
Continuous right turn movements
Complex signal operations, traffic circles, and Wide streets. 

Advice from organizations representing pedestrians who have disabilities should be given deference; and there should be widespread agreement that there is community demand for accessible pedestrian signals.

## New Guidance 

- Size, number and location on signal faces by approach, section 4D.15
- the following new GUIDANCE is provided for when to consider installing 12 inch signals:
- “at locations where there is a significant percentage of elderly drivers.”

**Notes:**
The following new GUIDANCE is provided for when to consider installing 12 inch signals:
“At locations where there is a significant percentage of elderly drivers.”

## New Guidance (cont’d)

- Provisions for pedestrians (4D.03)
- added guidance for safety considerations to include the installation of accessible pedestrian signals, where appropriate
- reflects the intent in TEA-21

**Notes:**
Safety considerations for pedestrians should include the installation, where appropriate, of accessible pedestrian signals (see Sections 4E.06 and 4E.08) that provide information in non-visual format (such as audible tones, verbal messages, and/or vibrating surfaces).”

This guidance was not in the 1988 MUTCD. This change reflects the intent of language on Bicycle Transportation and Pedestrian Walkways contained in section 1202 of the Transportation Equity Act for the 21st Century (TEA-21), Public Law 105-178, 112 Stat. 107 (1998).

## New Guidance (cont’d)

- Size, number, and location of signal faces by approach (4D.15)
- added new guidance to recommend using 300mm (12 inches) signal lenses under four conditions, specifically, where there is a significant percentage of elderly drivers

**Notes:**
A new paragraph D states that three-hundred millimeter (12 in) signal lenses should be used for all signal indications for four conditions, specifically, “locations where there is a significant percentage of elderly drivers.”

This guidance was not in the 1988 MUTCD. Several comments were received that objected to the Support paragraph proposed in Section 4D.16 of the 1999 Notice of Proposed Amendment.  Most of the commentors stated that the Standards and Guidance found elsewhere in Chapter 4D adequately addressed the decision as to which size lenses to use.  The FHWA decided the new paragraph D was a more appropriate location for this information.

## Changes in Guidance

- Pedestrian intervals and signal phases (4E.09)
- guidance changed from 4 to 7 seconds to at least 7 seconds
- option added to keep the 4 second timing if pedestrian volumes and characteristics do not require a 7 second walk interval

**Notes:**
Except as noted in the Option, the walk interval should be at least 7 second in length so that pedestrians will have adequate opportunity to leave the curb or shoulder before the pedestrian clearance time begins.   The Option states that if it is desired to favor the length of an opposing signal phase and if pedestrian volumes and characteristics do not require a 7-second walk interval, walk intervals as short as 4 seconds may be used.

The Option was provided to provide for a reduced the walk time if conditions at an intersection don’t warrant a 7 second walk interval.  There was no change made to how the pedestrian clearance time is calculated.

## New Option

- Application of steady signal indications for left turns (4D.06)
- in areas having a high percentage of elderly drivers, consideration may be given to use the protected only mode for left turn phasing

**Notes:**
When controlling left-turning traffic, FHWA has included an option for state and local agencies to consider using protected only mode for signal phasing in areas having a high percentage of elderly drivers.

## New Option (cont’d)

- Pedestrian intervals and signal phases (4E.09)
- OPTION added to use passive pedestrian detection equipment in crosswalks to extend the length of the pedestrian clearance time for a particular cycle when a pedestrian needs more time to cross the street

**Notes:**
There has been a successful experiment in Portland, Oregon, on the use of passive methods to detect pedestrians in the crosswalk.  FHWA wants to encourage jurisdictions to use alternate methods, such as passive pedestrian detection, to accommodate the needs of all road users. 

## Questions?

**Notes:**
Questions?