Shortening or omitting a pedestrian change interval when transitioning into preemption

Transcription

1 Signals #1 NOTE: This is a recommendation by the Signals Technical Committee of the NCUTCD. It is being distributed to the NC Sponsoring agencies for review and is subject to revision. This recommendation is not a revision to the MUTCD and does not constitute official standards, guidance, or options. No proposed revision to the MUTCD is effective unless and until approved by FHWA through an Interim Approval or through the Federal rulemaking process. TECHNICAL COMMITTEE: TOPIC: STATUS/DATE OF ACTION: Signals Approval: Signals Technical Committee (STC) Shortening or omitting a pedestrian change interval when transitioning into preemption Recommended by Signals Technical Committee 06/20/2012, send to Sponsors June FOR, 1 OPPOSED Transmitted to Sponsors: July 2012 Council Approval: ORIGIN OF REQUEST: Signals Technical Committee AFFECTED SECTIONS OF MUTCD: 4D.27 SUMMARY: Section 4D.27 of the MUTCD prohibits the shortening or omission of a pedestrian change interval during priority control and during the transition into or out of priority control (4D.27 paragraph 10 D). It permits the shortening or omission of a pedestrian change interval during the transition into preemption control (4D.27 paragraph 08 B). This recommendation is to prohibit the shortening or omission of a pedestrian change interval when transitioning into preemption operation for an emergency vehicle. Shortening or omitting a pedestrian change interval would continue to be permitted when transitioning into preemption control for other than emergency vehicles. DISCUSSION Pedestrian change intervals are generally timed to permit a pedestrian to cross a street at a walking speed of 3.5 feet per second or slower. Many pedestrians are unable to complete crossings in less time. Drivers of emergency vehicles are trained to be alert to the presence of pedestrians who may still be in the travelled way during preemption,

2 and to be prepared to avoid them. However, other drivers may be unaware that emergency vehicles can affect signal operation and possibly alter pedestrian signal timings. Most other drivers, when they see a green signal for their movement, assume that there should no longer be pedestrians in their path and they therefore do not use extra caution as they proceed. Pedestrians that are particularly at risk in this conflict situation include those with limited or reduced mobility, whether due to age or disability, pedestrians that are deaf or that have severing hearing loss and therefore may not be able to hear any warning devices on the approaching vehicle, and pedestrians who are visually impaired and be unable to see the changing signal or the direction and distance of the approaching emergency vehicle. Ideally, it would not be necessary to shorten or omit a pedestrian change interval when transitioning from normal operation into preemption control. However, it is recognized that it is sometimes necessary to shorten or omit a pedestrian change interval when a train or boat that cannot stop or alter their course is approaching. The MUTCD currently permits a pedestrian change interval to be shortened or omitted when transitioning into preemption control regardless of the reason for the preemption. Unlike boats and trains, emergency vehicles generally have the ability to slow, stop, or alter their course if necessary to avoid a collision. Therefore, the STC recommends that that MUTCD be revised to prohibit the shortening or omission of a pedestrian change interval when transitioning into preemption control for an emergency vehicle. The shortening or omission of a pedestrian change interval would continue to be permitted when transitioning into preemption for anything other than an emergency vehicle. This recommendation only includes changes when transitioning into preemption control. It does not include any changes to signal operation during preemption control, when transitioning out of preemption control, during priority control, or during the transition into or out of priority control. RECOMMENDED CHANGES TO THE MUTCD (Section 4D.27) Note: Recommended additions to the MUTCD are shown in blue underline and recommended deletions are shown in red double strikethrough. Section 4D.27 Preemption and Priority Control of Traffic Control Signals Traffic control signals may be designed and operated to respond to certain classes of approaching vehicles by altering the normal signal timing and phasing plan(s) during the approach and passage of those vehicles. The alternative plan(s) may be as simple as extending a currently displayed green interval or as complex as replacing the entire set of signal phases and timing. Support: Preemption control (see definition in Section 1A.13) is typically given to trains, boats, emergency vehicles, and light rail transit. Examples of preemption control include the following: A. The prompt displaying of green signal indications at signalized locations ahead of fire vehicles, law enforcement vehicles, ambulances, and other official emergency vehicles;

3 B. A special sequence of signal phases and timing to expedite and/or provide additional clearance time for vehicles to clear the tracks prior to the arrival of rail traffic; and C. A special sequence of signal phases to display a steady red indication to prohibit turning movements toward the tracks during the approach or passage of rail traffic. Priority control (see definition in Section 1A.13) is typically given to certain nonemergency vehicles such as light-rail transit vehicles operating in a mixed-use alignment and buses. Examples of priority control include the following: A. The displaying of early or extended green signal indications at an intersection to assist public transit vehicles in remaining on schedule, and B. Special phasing to assist public transit vehicles in entering the travel stream ahead of the platoon of traffic. Some types or classes of vehicles supersede others when a traffic control signal responds to more than one type or class. In general, a vehicle that is more difficult to control supersedes a vehicle that is easier to control. Preemption or priority control of traffic control signals may also be a means of assigning priority right-of-way to specified classes of vehicles at certain non-intersection locations such as on approaches to one-lane bridges and tunnels, movable bridges, highway maintenance and construction activities, metered freeway entrance ramps, and transit operations. During the transition into preemption control: A. The yellow change interval, and any red clearance interval that follows, shall not be shortened or omitted. B. The shortening or omission of any pedestrian walk interval and/or pedestrian change interval shall be permitted. B. The shortening or omission of any pedestrian walk interval shall be permitted. C. The shortening or omission of any pedestrian change interval shall be permitted except for emergency vehicles. DC. The return to the previous green signal indication shall be permitted following a steady yellow signal indication in the same signal face, omitting the red clearance interval, if any. During preemption control and during the transition out of preemption control: A. The shortening or omission of any yellow change interval, and of any red clearance interval that follows, shall not be permitted. B. A signal indication sequence from a steady yellow signal indication to a green signal indication shall not be permitted. During priority control and during the transition into or out of priority control: A. The shortening or omission of any yellow change interval, and of any red clearance interval that follows, shall not be permitted. B. The shortening of any pedestrian walk interval below that time described in Section 4E.06 shall not be permitted. C. The omission of a pedestrian walk interval and its associated change interval shall not be permitted unless the associated vehicular phase is also omitted or the pedestrian phase is exclusive. D. The shortening or omission of any pedestrian change interval shall not be permitted.

4 E. A signal indication sequence from a steady yellow signal indication to a green signal indication shall not be permitted. Guidance: Except for traffic control signals interconnected with light rail transit systems, traffic control signals with railroad preemption or coordinated with flashing-light signal systems should be provided with a back-up power supply. When a traffic control signal that is returning to a steady mode from a dark mode (typically upon restoration from a power failure) receives a preemption or priority request, care should be exercised to minimize the possibility of vehicles or pedestrians being misdirected into a conflict with the vehicle making the request. During the change from a dark mode to a steady mode under a preemption or priority request, the display of signal indications that could misdirect road users may be prevented by one or more of the following methods: A. Having the traffic control signal remain in the dark mode, B. Having the traffic control signal remain in the flashing mode, C. Altering the flashing mode, D. Executing the normal start-up routine before responding, or E. Responding directly to initial or dwell period. Guidance: If a traffic control signal is installed near or within a grade crossing or if a grade crossing with active traffic control devices is within or near a signalized highway intersection, Chapter 8C should be consulted. Traffic control signals operating under preemption control or under priority control should be operated in a manner designed to keep traffic moving. Traffic control signals that are designed to respond under preemption or priority control to more than one type or class of vehicle should be designed to respond in the relative order of importance or difficulty in stopping the type or class of vehicle. The order of priority should be: train, boat, heavy vehicle (fire vehicle, emergency medical service), light vehicle (law enforcement), light rail transit, rubber-tired transit. A distinctive indication may be provided at the intersection to show that an emergency vehicle has been given control of the traffic control signal (see Section of the Uniform Vehicle Code ). In order to assist in the understanding of the control of the traffic signal, a common distinctive indication may be used where drivers from different agencies travel through the same intersection when responding to emergencies. If engineering judgment indicates that light rail transit signal indications would reduce road user confusion that might otherwise occur if standard traffic signal indications were used to control these movements, light rail transit signal indications complying with Section 8C.11 and as illustrated in Figure 8C-3 may be used for preemption or priority control of the following exclusive movements at signalized intersections: A. Public transit buses in queue jumper lanes, and B. Bus rapid transit in semi-exclusive or mixed-use alignments.

5 Signals #2 NOTE: This is a recommendation by the Signals Technical Committee of the NCUTCD. It is being distributed to the NC Sponsoring agencies for review and is subject to revision. This recommendation is not a revision to the MUTCD and does not constitute official standards, guidance, or options. No proposed revision to the MUTCD is effective unless and until approved by FHWA through an Interim Approval or through the Federal rulemaking process. TECHNICAL COMMITTEE: TOPIC: STATUS/DATE OF ACTION: Signals Approval: Signals Technical Committee (STC) Prohibiting flashing beacons within the border of a sign Recommended by Signals Technical Committee 06/20/2012, send to Sponsors June 2012 Unanimous FOR Transmitted to Sponsors: July 2012 Council Approval: ORIGIN OF REQUEST: NC Honorary Member Jim Pline and the Signals Technical Committee AFFECTED SECTIONS OF MUTCD: 4L.01 & 4L.04 SUMMARY: Section 4L.01 of the MUTCD prohibits flashing beacons within the border of a sign but an exception is listed permitting a beacon to be within the border of a school speed limit sign. There is also an option included in Section 4L.04 permitting beacon placement within the border of a school speed limit sign. While prior versions of the MUTCD included language in Part 7 (Traffic Control for School Areas) that permitted this, it is not addressed in Part 7 in the current MUTCD. The school speed limit sign is the only sign permitted to have beacons within its border. The NCUTCD previously approved a recommendation that included prohibiting beacons within the border of a sign. The Signals Technical Committee recommends that the exception and option permitting beacons to be within the border of a school speed limit sign be deleted and that such beacon placement be prohibited for these signs as it is for all other signs.

6 Jim Pline pointed out this issue during NC Council discussion and action on beacon sizes at the January 2012 meeting. However, this issue was not included in the beacon size information sent to sponsors or presented to the NC Council. It was therefore not included in that action and is being addressed separately in this recommendation. DISCUSSION There was specific permission to have the beacons within the face of the sign in Section 7D-24 of the 1988 MUTCD. From 1988 MUTCD The 2000 MUTCD eliminated all the wording in multiple sections in Part 7 relating to signals. From NPA for 2000 MUTCD The FHWA proposes deleting the discussion in Chapter 7D for school traffic signals and including a reference to the proposed text in the rewrite of Part 4.

7 However, the Final Rule notes that the option to include the beacons within the signs was added to Part 4 to be consistent with 7B.10. (It actually turned on to be 7B.11 in the final MUTCD). From Final Rule for 2000 MUTCD 164. In Section 4K.03 Warning Beacon, the FHWA is adding the phrase except for SCHOOL SPEED LIMIT sign beacons to the second paragraph in the STANDARD statement to clarify that SCHOOL SPEED LIMIT sign beacons are allowed to be included within the border of the sign to be consistent with Section 7B.10. Section 7B.11 of the 2000 MUTCD included a sentence specifically allowing this. From 2000 MUTCD Section 7B.11 School Speed Limit Assembly (S4-1, S4-2, S4-3, S4-4, S5-1) A Speed Limit Sign Beacon also may be used, with a WHEN FLASHING legend, to identify the periods that the school speed limit is in effect. The lenses of the Speed Limit Sign Beacon may be positioned within the face of the School Speed Limit (S5-1) sign. Section 7B.11 of the 2003 MUTCD also included a sentence specifically allowing this. From 2003 MUTCD Section 7B.11 School Speed Limit Assembly (S4-1, S4-2, S4-3, S4-4, S4-6, S5-1) A Speed Limit Sign Beacon also may be used, with a WHEN FLASHING legend, to identify the periods that the school speed limit is in effect. The lenses of the Speed Limit Sign Beacon may be positioned within the face of the School Speed Limit (S5-1) sign (see Figure 7B-1). A check of the NPA for the 2009 MUTCD did not identify any proposal to eliminate this option. However, there was a note in the Final Rule for the 2009 MUTCD that the NCUTCD and a State DOT recommended the elimination of the option. FHWA agreed that this is an obsolete practice, but declined to make the change as part of the Final Rule. They noted it might be considered for future rulemaking. They did note that the option was being removed from 7B.15 and a cross reference to 4L.04 added. From Final Rule for 2009 MUTCD (Pg 66846, Item 530) The NCUTCD and a State DOT recommended removal of the existing OPTION statement that allows the use of the signal indications of the Speed Limit Sign Beacon to be positioned within the face of the School Speed Limit (S5 1) sign. This statement mirrors a similar OPTION in Section 4L.04 Speed Limit Sign Beacon. This sign is the only instance where beacons are allowed within a sign face. Under certain light and weather conditions, the flashing beacon causes halation that obscures the sign message. The FHWA agrees that this is an obsolete practice but declines to remove the option at this time. The FHWA might consider this for a future rulemaking. However, the FHWA removes the OPTION from Section 7B.15 and instead provides a cross-reference to Section 4L.04 in this final rule. Following is the prior NC Council recommendation on this item: From NC response to the docket 7/31/08 TECHNICAL COMMITTEE: Regulatory & Warning Signs

8 TOPIC: Part 7 FHWA NPA 01/02/2008 STATUS/DATE OF ACTION Task Force Approved 06/02/2008 TECH COMM DRAFTS: 01/10/2008, 04/22/2008, 06/02/2008 TECH COMM APPROVAL: 01/10/2008, 06/19/2008 TRANSMITTED TO SPONSORS: COUNCIL APPROVAL: Of Text: 01/11/2008 and 06/21/2008 Of Table & Figures: 06/21/2008 ORIGIN OF REQUEST: National Committee review of NPA MUTCD SECTIONS: Part 7, Figures 7A-1, 7B-1 thru 7B-5 and Table 7B-1 (Table and Figures in separate file) SUMMARY: The FHWA published a Notice of Rulemaking in the Federal Register on January 2, 2008, covering the MUTCD Revisions for the 2009 Manual. The RWSTC reviewed the proposed Part 7 of the NPA, exclusive of Chapter 7C Markings and Figure 7C-1 and recommended the changes noted herein. The National Committee Council approved text changes on January 11, 2008 and on June 21, 2008 it approved several additional text changes recommended by the School Area Task Force and by the Bicycles Technical Committee. On June 21, 2008, the National Committee also approved the Part 7 table and figures as approved by the RWSTC. NPA showing FHWA s proposed revisions to the 2003 MUTCD Deletions: Red double strikethrough Insertions: Blue underline Comments: Green highlight Proposed National Committee changes and comments Approved by Council on 01/11/2008: Red Highlighted in Turquoise Approved by Council on 06/21/2008: Red Highlighted in Yellow Deletions: Single Strikethrough Insertions: Underlined Rationale and Comments: Bold Black Highlighted in Yellow A Speed Limit Sign Beacon (see Section 4L.04) also may be used, with a WHEN FLASHING legend, to identify the periods that the school speed limit is in effect. The signal lenses indications of the Speed Limit Sign Beacon may be positioned within the face of the School Speed Limit (S5-1) sign (see Figure 7B-1). Reason: It is well known that under certain light and weather conditions, the flashing beacon causes halation that obscures the sign message. Therefore, it is inappropriate to permit a sign design where the sign legend would not be legible. A flashing beacon is not permitted within the border of any other sign. Other flashing beacons used with signs must have at least a 12 inch separation from the sign face. The internal Flasher-School Speed Limit sign was/has been manufactured for many years, recognized by some state codes, and used by some school districts. It apparently has been retained in the MUTCD so that those schools do not have to replace existing signs. Many of those older signs are

9 becoming obsolete and inoperable although some still are in use. Note, Similar change needed to Sections 4L.01 and 4L.04. The NPA for the 2009 MUTCD did not include a proposal to prohibit beacons within the border of school speed zone signs. This was likely a consideration in the FHWA decision to not include the prohibition in the 2009 MUTCD while noting that it is an obsolete practice. The reasons for prohibiting such placement stated in the NC response to the docket remain valid today. Therefore, the STC recommends that the NC Council reaffirm its prior recommendation that the exception and option permitting beacons to be within the border of a school speed limit sign be deleted and that such beacon placement be prohibited for these signs as it is for all other signs. RECOMMENDED CHANGES TO THE MUTCD (Section 4L.01 and 4L.04) Note: There are no recommended additions to the MUTCD. Recommended deletions are shown in red double strikethrough. Section 4L.01 General Design and Operation of Flashing Beacons Support: 01 A Flashing Beacon is a highway traffic signal with one or more signal sections that operates in a flashing mode. It can provide traffic control when used as an intersection control beacon (see Section 4L.02) or it can provide warning when used in other applications (see Sections 4L.03, 4L.04, and 4L.05). 02 Flashing Beacon units and their mountings shall comply with the provisions of Chapter 4D, except as otherwise provided in this Chapter. 03 Beacons shall be flashed at a rate of not less than 50 or more than 60 times per minute. The illuminated period of each flash shall be a minimum of 1/2 and a maximum of 2/3 of the total cycle. 04 A beacon shall not be included within the border of a sign except for SCHOOL SPEED LIMIT sign beacons (see Sections 4L.04 and 7B.15). Guidance: 05 If used to supplement a warning or regulatory sign, the edge of the beacon signal housing should normally be located no closer than 12 inches outside of the nearest edge of the sign. 06 An automatic dimming device may be used to reduce the brilliance of flashing yellow signal indications during night operation. Section 4L.04 Speed Limit Sign Beacon 01 A Speed Limit Sign Beacon shall be used only to supplement a Speed Limit sign. 02 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

10 signal indication in each signal section. The signal indications shall have a nominal diameter of not less than 8 inches. If two signal indications are used, they shall be vertically aligned, except that they shall be permitted to be horizontally aligned if the Speed Limit (R2-1) sign is longer horizontally than vertically. If two signal indications are used, they shall be alternately flashed. 03 A Speed Limit Sign Beacon may be used with a fixed or variable Speed Limit sign. If applicable, a flashing Speed Limit Sign Beacon (with an appropriate accompanying sign) may be used to indicate that the displayed speed limit is in effect. 04 A Speed Limit Sign Beacon may be included within the border of a School Speed Limit (S5-1) sign(see Section 7B.15) Note: Section 7B.15 is shown for reference only. No changes are proposed to this section. Section 7B.15 School Speed Limit Assembly (S4-1P, S4-2P, S4-3P, S4-4P, S4 6P, S5-1) and END SCHOOL SPEED LIMIT Sign (S5-3) 01 A School Speed Limit assembly (see Figure 7B-1) or a School Speed Limit (S5-1) sign (see Figure 7B-1) shall be used to indicate the speed limit where a reduced school speed limit zone has been established based upon an engineering study or where a reduced school speed limit is specified for such areas by statute. The School Speed Limit assembly or School Speed Limit sign shall be placed at or as near as practical to the point where the reduced school speed limit zone begins (see Figures 7B-3 and 7B-5). 02 If a reduced school speed limit zone has been established, a School (S1-1) sign shall be installed in advance (see Table 2C-4 for advance placement guidelines) of the first School Speed Limit sign assembly or S5-1 sign that is encountered in each direction as traffic approaches the reduced school speed limit zone (see Figures 7B-3 and 7B-5). 03 Where increased fines are imposed for traffic violations within a reduced school speed limit zone, a FINES HIGHER (R2-6P), FINES DOUBLE (R2-6aP), or $XX FINE (R2-6bP) plaque (see Figure 2B-3) shall be installed as a supplement to the reduced school speed limit sign to notify road users. 04 Except as provided in Paragraph 5, the downstream end of an authorized and posted reduced school speed limit zone shall be identified with an END SCHOOL SPEED LIMIT (S5-3) sign (see Figures 7B-1 and 7B-5). 05 If a reduced school speed limit zone ends at the same point as a higher fines zone, an END SCHOOL ZONE (S5-2) sign may be used instead of a combination of an END HIGHER FINES ZONE (R2-11) sign and an END SCHOOL SPEED LIMIT (S5-3) sign. 06 A standard Speed Limit sign showing the speed limit for the section of highway that is downstream from the authorized and posted reduced school speed limit zone may be mounted on the same post above the END SCHOOL SPEED LIMIT (S5-3) sign or the END SCHOOL ZONE (S5-2) sign. Guidance:

11 07 The beginning point of a reduced school speed limit zone should be at least 200 feet in advance of the school grounds, a school crossing, or other school related activities; however, this 200-foot distance should be increased if the reduced school speed limit is 30 mph or higher. 08 The School Speed Limit assembly shall be either a fixed-message sign assembly or a changeable message sign. 09 The fixed-message School Speed Limit assembly shall consist of a top plaque (S4-3P) with the legend SCHOOL, a Speed Limit (R2-1) sign, and a bottom plaque (S4-1P, S4-2P, S4-4P, or S4-6P) indicating the specific periods of the day and/or days of the week that the special school speed limit is in effect (see Figure 7B-1). 10 Changeable message signs (see Chapter 2L and Section 6F.60) may be used to inform drivers of the school speed limit. If the sign is internally illuminated, it may have a white legend on a black background. Changeable message signs with flashing beacons may be used for situations where greater emphasis of the special school speed limit is needed. Guidance: 11 Even though it might not always be practical because of special features to make changeable message signs conform in all respects to the standards in this Manual for fixedmessage signs, during the periods that the school speed limit is in effect, their basic shape, message, legend layout, and colors should comply with the standards for fixed-message signs. 12 A confirmation light or device to indicate that the speed limit message is in operation should be considered for inclusion on the back of the changeable message sign. 13 Fluorescent yellow-green pixels shall be used when the SCHOOL message is displayed on a changeable message sign for a school speed limit. 14 Changeable message signs may use blank-out messages or other methods in order to display the school speed limit only during the periods it applies. 15 Changeable message signs that display the speed of approaching drivers (see Section 2B.13) may be used in a school speed limit zone. 16 A Speed Limit Sign Beacon (see Section 4L.04) also may be used, with a WHEN FLASHING legend, to identify the periods that the school speed limit is in effect.