36 CFR Part 1190, Proposed Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way: Notice of Proposed Rulemaking (NPRM)

Chapter R3: Technical Requirements (Section-by-Section Analysis)

Technical requirements specify what design criteria elements, spaces, and facilities must comply with in order to be considered accessible.

R301 General (Section-by-Section Analysis)

The technical requirements in Chapter R3 apply where required by the scoping requirements in Chapter R2, or where referenced by another technical requirement in Chapters R3 or R4.

R302 Pedestrian Access Routes (Section-by-Section Analysis)

General (R302.1) (Section-by-Section Analysis)

The technical requirements for pedestrian access routes are contained in R302, and adapt the technical requirements for accessible routes in the 2004 ADA and ABA Accessibility Guidelines to the public right-of-way. In alterations where existing physical constraints make it impractical to fully comply with the technical requirements, compliance is required to the extent practicable within the scope of the project (see R202.3.1).

Components (R302.2) (Section-by-Section Analysis)

The components of pedestrian access routes and the technical requirements for each component are listed in R302.2. Sidewalks and other pedestrian circulation paths, pedestrian street crossings, and pedestrian overpasses and underpasses and similar structures must comply with all the technical requirements in R302.3 through R302.7. Curb ramps and blended transitions must comply with the technical requirements in R302.7 and R304. Ramps must comply with the technical requirements in R407. Elevators, limited use/limited application elevators, platform lifts, and doors, doorways, and gates must comply with applicable technical requirements in the 2004 ADA and ABA Accessibility Guidelines.

Continuous Width (R302.3) (Section-by-Section Analysis)

The continuous clear width of pedestrian access routes (exclusive of the width of the curb) must be 1.2 meters (4 feet) minimum, except for medians and pedestrian refuge islands where the clear width must be 1.5 meters (5 feet) minimum in order to allow for passing space. The AASHTO “Guide for the Planning, Design, and Operation of Pedestrian Facilities” recommends that sidewalks be wider than 1.2 meters (4 feet), particularly in urban areas. Where sidewalks are wider than 1.2 meters (4 feet), only a portion of the sidewalk is required to comply with the technical requirements in R302.3 through R302.7.

The advisory committee recommended a minimum width of 1.5 meters (5 feet) for pedestrian access routes. The proposed guidelines specify a minimum width of 1.2 meters (4 feet) in order to allow for street furniture and other objects that may be located on sidewalks. R210 prohibits street furniture and other objects from reducing the clear width required for pedestrian access routes. A minimum width of 1.2 meters (4 feet) will accommodate turns at intersections and building entrances. Advisory information recommends additional maneuvering clearance at turns or changes in direction, recesses and alcoves, building entrances, and along curved or angled routes, particularly where the grade exceeds 5 percent.

Passing Spaces (R302.4) (Section-by-Section Analysis)

Where the clear width of pedestrian access routes is less than 1.5 meters (5 feet), passing spaces must be provided at intervals of 61 meters (200 feet) maximum. Passing spaces must be 1.5 meters (5 feet) minimum by 1.5 meters (5 feet) minimum. Passing spaces are permitted to overlap pedestrian access routes.

Grade (R302.5) (Section-by-Section Analysis)

Grade is the slope parallel to the direction of pedestrian travel. Grade is calculated by dividing the vertical change in elevation by the horizontal distance covered, and is expressed as a percent. Where pedestrian access routes are contained within a street or highway right-of-way, the grade of the pedestrian access route is permitted to equal the general grade established for the adjacent street or highway, except that where pedestrian access routes are contained within pedestrian street crossings a maximum grade of 5 percent is required. This is consistent with the AASHTO “Policy on Geometric Design of Highways and Streets” which recommends that the sidewalk grade follow the grade of adjacent roadways, and also recommends maximum cross slopes for roadways. Where pedestrian access routes are not contained within a street or highway right-of-way, a maximum grade of 5 percent is required.

Cross Slope (R302.6) (Section-by-Section Analysis)

Cross slope is the slope perpendicular to the direction of pedestrian travel (see R105.5). On a sidewalk, cross slope is measured perpendicular to the curb line or edge of the street or highway. Cross slope impedes travel by pedestrians who use wheeled mobility devices since energy must be expended to counteract the perpendicular force of the cross slope. Cross slope makes it more difficult for pedestrians who use wheelchairs to travel on uphill slopes and to maintain balance and control on downhill slopes. Cross slope also negatively affects pedestrians who use braces, lower limb prostheses, crutches, or walkers, as well as pedestrians who have gait, balance, or stamina impairments. The maximum cross slope permitted on accessible routes in the 2004 ADA and ABA Accessibility Guidelines is 2 percent. In exterior environments, a maximum cross slope of 2 percent is generally accepted as adequate to allow water to drain off paved walking surfaces.

A maximum cross slope of 2 percent is specified for pedestrian access routes, except for pedestrian access routes contained within certain pedestrian street crossings in order to allow for typical roadway geometry. A 5 percent maximum cross slope is specified for pedestrian access routes contained within pedestrian street crossings without yield or stop control to avoid any unintended negative impacts on the control and safety of vehicles, their occupants, and pedestrians in the vicinity of the intersection. Pedestrian street crossings without yield or stop control are crossings where there is no yield or stop sign, or where there is a traffic signal that is designed for the green phase. At pedestrian street crossings without yield or stop control vehicles can proceed through the intersection without slowing or stopping. The cross slope of pedestrian access routes contained within midblock pedestrian street crossings is permitted to equal the street or highway grade.

Question 13. Comments are requested on whether the description of pedestrian street crossings without yield or stop control is clear, or whether there is a better way to describe such crossings?

In new construction, where pedestrian access routes within sidewalks intersect at corners, the 2 percent maximum cross slope requirement will result in level corners (i.e., the slope at the corners will not exceed 2 percent in each direction of pedestrian travel). The level corners will provide a platform for providing level spaces for curb ramps and blended transitions, pedestrian street crossings, and accessible pedestrian signals and pedestrian pushbuttons.

Newly Constructed Tabled Intersections That Contain Pedestrian Street Crossings With Yield or Stop Control (Section-by-Section Analysis)

The 2 percent maximum cross slope requirement applies to pedestrian access routes within pedestrian street crossings with yield or stop control where vehicles slow or stop before proceeding through the intersection. The cross slope of the pedestrian access route within the pedestrian street crossing is the longitudinal grade of the street being crossed, and the 2 percent maximum cross slope requirement will impact the vertical alignment of streets in the vicinity of the intersection. In new construction, street intersections in hilly urban areas are typically cut-and filled to produce relative flat or tabled intersections. Where pedestrian street crossings with yield or stop control are provided at newly constructed tabled intersections, the tabling would be extended to the pedestrian street crossings to comply with the 2 percent maximum cross slope for pedestrian access routes within the pedestrian street crossings.

Question 14. The Access Board seeks information on the current design policies and practices of state and local transportation departments with respect to tabling newly constructed intersections in hilly urban areas, and particularly whether the tabling is extended to pedestrian street crossings with yield or stop control.

In new construction, extending the tabling of intersections to pedestrian street crossings with yield or stop control involves additional costs for site preparation, grading, and earthwork. The Volpe Center roughly estimated the additional costs to extend the tabling to pedestrian street crossings with yield or stop control to be $60,000 per intersection based on information provided by a transportation official to the Access Board. The costs will vary by site.

Question 15. The Access Board seeks information on the additional costs to extend the tabling of newly constructed intersections in hilly urban areas to pedestrian street crossings with yield or stop control.

Question 16. The Access Board seeks information on number of tabled intersections which contain pedestrian street crossings with yield or stop control that are newly constructed in hilly urban areas on an annual basis by state and local transportation departments.

Surfaces (R302.7) (Section-by-Section Analysis)

The proposed technical requirements for surfaces apply to pedestrian access routes, including curb ramps and blended transitions, and accessible elements and spaces that connect to pedestrian access routes. An advisory section lists the accessible elements and spaces that connect to pedestrian access routes and are required to comply with the technical requirements for surfaces.

The surfaces of pedestrian access routes and the surfaces at accessible elements and spaces that connect to pedestrian access routes must be firm, stable, and slip resistant. Vertical alignment of surfaces within pedestrian access routes (including curb ramp runs, blended transitions, turning spaces, and gutter areas within pedestrian access routes) and within the surfaces at accessible elements and spaces that connect to pedestrian access routes must be generally planar. Grade breaks (i.e., the line where two surface planes with different grades meet, see R105.5) must be flush. Where pedestrian access routes cross rails at grade, the pedestrian access route must be level and flush with the top of the rail at the outer edges of the rails, and the surfaces between the rails must be aligned with the top of the rail.

Vertical surface discontinuities (i.e., vertical difference in level between two adjacent surfaces, see R105.5) must be 13 millimeters (0.5 inch) maximum. Vertical surface discontinuities between 6.4 millimeters (0.25 inch) and 13 millimeters (0.5 inch) must be beveled with a slope not steeper than 50 percent, and the bevel must be applied across the entire vertical surface discontinuity. Horizontal openings in gratings and joints must not permit the passage of a sphere more than 13 millimeters (0.5 inch) in diameter. Elongated openings in gratings must be placed so that the long dimension is perpendicular to the dominant direction of travel.

Flangeway gaps at pedestrian at-grade rail crossings must be 64 millimeters (2.5 inches) maximum on non-freight rail track, and 75 millimeters (3 inches) maximum on freight rail track. These are the typical gaps required to allow passage of train wheel flanges. The flangeway gaps are wider than the maximum gap allowed for horizontal openings in other surfaces. These wider flangeway gaps pose a potential safety hazard to pedestrians who use wheelchairs because the gap can entrap the wheelchair casters.³⁹  The Federal Railroad Administration is sponsoring research to develop materials or devices that will fill the flangeway gap under light loads of a wheelchair but will compress or retract when a train wheel flange passes over it.⁴⁰  The materials or devices will be tested under heavy and light train loads for safety, effectiveness, durability, and cost.

Question 17. The Access Board seeks information on materials and devices that fill the flangeway gap, and any related research and sources of expertise.

³⁹For additional information on the potential safety hazard of flangeway gaps, see “Wheelchair Safety at Rail Level Crossings, International Review Working Paper” (2003) athttp://www.transport.vic.gov.au/DOI/DOIElect.nsf/$UNIDS+for+Web+Display/43D9BDF138FFE9F9CA256D630011A607/$FILE/Rail_Crossing_Disability_Access-International_Review.pdf; and “Rail Crossing Disability Access Kit” (2003) available at: http://www.transport.vic.gov.au/DOI/DOIElect.nsf/UNIDS+for+Web+Display/E995EA3FEB44F07CCA256D630011AD71/$FILE/Rail_Crossing_Disability_Access-Toolkit.pdf.

⁴⁰For announcement of award of research contact in 2010, see http://www.volpe.dot.gov/sbir/ph1rec10.html and http://www.integran.com/news/IT%20USA%20DOT%20Flangeway%20Gap%20SBIR%20-%20100323.pdf. The Transportation Research Board has also developed research need statements for reducing flangeway gaps at railroad crossings. See “Wheelchairs Crossing Flangeway Gaps at Railroad Crossings” (2007); and “Reducing Flangeway Gaps at Railroad Crossings to Better Accommodate Pedestrians” (2008). The research need statements are available at: http://rns.trb.org/dproject.asp?n=13462 and http://rns.trb.org/dproject.asp?n=17644.

R303 Alternate Pedestrian Access Routes (See R205) (Section-by-Section Analysis)

In the 2005 draft of the proposed guidelines, the technical requirements for alternate pedestrian access routes were contained in Chapter R3. The proposed guidelines reference MUTCD standards for alternate pedestrian access routes in the scoping requirements at R205. This section heading is included in Chapter R3 of the proposed guidelines to notify readers who were familiar with the 2005 draft of the proposed guidelines where to find the requirements for alternate pedestrian access routes. This section heading will not be included in the final guidelines.

R304 Curb Ramps and Blended Transitions (Section-by-Section Analysis)

General (R304.1) (Section-by-Section Analysis)

Curb ramps are ramps that are cut through or built up to the curb (see R105.5). Curb ramps can be perpendicular or parallel, or a combination of parallel and perpendicular ramps. Blended transitions are raised pedestrian street crossings, depressed corners, or similar connections between the pedestrian access route at the level of the sidewalk and the level of the pedestrian street crossing that have a grade of 5 percent or less (see R105.5).

The technical requirements for curb ramps and blended transitions are contained in R304 and adapt the technical requirements for curb ramps in the 2004 ADA and ABA Accessibility Guidelines to the public right-of-way. In alterations where existing physical constraints make it impractical to fully comply with the technical requirements, compliance is required to the extent practicable within the scope of the project (see R202.3.1).

Perpendicular Curb Ramps (R304.2) (Section-by-Section Analysis)

Perpendicular curb ramps have a running slope that cuts through or is built up to the curb at right angles or meets the gutter grade break at right angles where the curb is curved. On corners with a large curb radius, it will be necessary to indent the gutter grade break on one side of the curb ramp in order for the curb ramp to meet the gutter grade break at right angles.

A turning space must be provided at the top of perpendicular curb ramps. The turning space must be 1.2 meters (4 feet) minimum by 1.2 meters (4 feet) minimum, and is permitted to overlap other turning spaces and clear spaces. Where the turning space is constrained at the back of the sidewalk, the turning space must be 1.2 meters (4 feet) minimum by 1.5 meters (5 feet) minimum, with the 1.5 meters (5 feet) dimension provided in the direction of the ramp run.

A minimum running slope of 5 percent and a maximum running slope of 8.3 percent are specified for perpendicular curb ramps, and the ramp length is limited to 4.5 meters (15 feet). A maximum running slope of 2 percent is specified for the turning space at the top of the curb ramp. The running slope is measured parallel to the direction of pedestrian travel.

A maximum slope of 10 percent is specified for the flared sides of perpendicular curb ramps where a pedestrian circulation path crosses the curb ramp. The flared sides are part of the pedestrian circulation path, but are not part of the pedestrian access route. The slope of the flared sides is measured parallel to the curb line. The 10 percent maximum slope for the flared sides is the same as in the 2004 ADA and ABA Accessibility Guidelines (see 403.6). Transportation officials have reported that the 10 percent maximum slope for the flared sides can make it difficult to provide two perpendicular curb ramps at some street corners due to the width of the flared sides at the base of the curb ramp. The Access Board is considering increasing the maximum slope for the flared sides to 12.5 percent or 16.7 percent to address this issue.

Question 18. Comments are requested on whether the maximum slope for the flared sides of perpendicular curb ramps should be increased from 10 percent to 12.5 percent or 16.7 percent, and what impact such a change would have on providing two perpendicular curb ramps at street corners. Comments are also requested on any public safety issues that may arise from increasing the maximum slope for the flared sides from 10 percent to 12.5 percent or 16.7 percent.

Parallel Curb Ramps (R304.3) (Section-by-Section Analysis)

Parallel curb ramps have a running slope that is in-line with the direction of sidewalk travel and lower the sidewalk to a level turning space where a turn is made to enter the pedestrian street crossing.

A turning space must be provided at the bottom of parallel curb ramps. The turning space must be 1.2 meters (4 feet) minimum by 1.2 meters (4 feet) minimum, and is permitted to overlap other turning spaces and clear spaces. Where the turning space is constrained on two or more sides, the turning space must be 1.2 meters (4 feet) minimum by 1.5 meters (5 feet) minimum, with the 1.5 meters (5 feet) dimension provided in the direction of the pedestrian street crossing.

A minimum running slope of 5 percent and a maximum running slope of 8.3 percent are specified for parallel curb ramps, and the ramp length is limited to 4.5 meters (15 feet). A maximum running slope of 2 percent is specified for the turning space at the bottom of the curb ramp. The running slope is measured parallel to the direction of pedestrian travel.

Blended Transitions (R304.4) (Section-by-Section Analysis)

A maximum running slope of 5 percent is specified for blended transitions. The running slope is measured parallel to the direction of pedestrian travel.

Common Requirements (R304.5) (Section-by-Section Analysis)

The clear width of curb ramp runs (excluding flared sides), blended transitions, and turning spaces must be 1.2 meters (4 feet) minimum. Grade breaks at the top and bottom of curb ramp runs must be perpendicular to the direction of the ramp run. Grade breaks are not permitted on the surface of ramp runs and turning spaces. Surface slopes that meet at grade breaks must be flush. A maximum cross slope of 2 percent is specified for curb ramps, blended transitions, and turning spaces. At pedestrian street crossings without yield or stop control and at midblock pedestrian street crossings, the cross slope is permitted to equal the street or highway grade. The cross slope is measured perpendicular to the direction of pedestrian travel. A maximum counter slope of 5 percent is specified for the gutter or street at the foot of curb ramp runs, blended transitions, and turning spaces. A clear space must be provided beyond the bottom of the grade break that is within the width of the pedestrian street crossing and wholly outside the parallel vehicle traffic lane. The clear space must be 1.2 meters (4 feet) minimum by 1.2 meters (4 feet) minimum.

R305 Detectable Warning Surfaces (Section-by-Section Analysis)

Detectable warning surfaces consist of truncated domes aligned in a square or radial grid pattern. The dimensions for dome size and dome spacing are the same as in the 2004 ADA and ABA Accessibility Guidelines. The detectable warning surfaces must contrast visually with adjacent gutter, street or highway, or pedestrian access route surface, either light-on-dark or dark-on-light. The detectable warning surfaces must extend 610 millimeters (2 feet) minimum in the direction of pedestrian travel. At curb ramps and blended transitions, detectable warning surfaces must extend the full width of the ramp run (excluding flared sides), blended transition, or turning space. At pedestrian at-grade rail crossings not located within a street or highway, detectable warning surfaces must extend the full width of the crossing. At boarding platforms for buses and rail vehicles, detectable warning surfaces must extend the full length of the public use areas of the platform. At boarding and alighting areas at sidewalk or street level transit stops for rail vehicles, detectable warning surfaces must extend the full length of the transit stop. The proposed technical requirements specify where detectable warning surfaces must be placed on perpendicular curb ramps, parallel cub ramps, blended transitions, pedestrian refuge islands, pedestrian at-grade rail crossings, boarding platforms for buses and rail vehicles, and boarding and alighting areas at sidewalk or street level transit stops for rail vehicles.

R306 Pedestrian Street Crossings (Section-by-Section Analysis)

The technical requirements in R306 address pedestrian signal phase timing and pedestrian street crossings at roundabouts and multi-lane channelized turn lanes.

Pedestrian Signal Phase Timing (Section-by-Section Analysis)

Pedestrian signal phase timing must comply with referenced MUTCD standards and use a pedestrian clearance time that is calculated based on pedestrian walking speed of 1.1 meters/second (3.5 feet/second) or less.

Roundabouts (Section-by-Section Analysis)

A roundabout is a circular intersection with yield control at entry, which permits a vehicle on the circulatory roadway to proceed, and with deflection of the approaching vehicle counter-clockwise around a central island (MUTCD section 1A.13). Pedestrian street crossings at roundabouts can be difficult for pedestrians who are blind or have low vision to identify because the crossings are located off to the side of the pedestrian circulation path around the street or highway. Where sidewalks are flush against the curb at roundabouts and pedestrian street crossing is not intended, a continuous and detectable edge treatment must be provided along the street side of the sidewalk at roundabouts. Detectable warning surfaces must not be used for edge treatment. Where chains, fencing, or railings are used for edge protection, the bottom edge of the treatment must be 380 millimeters (15 inches) maximum above the sidewalk to be detectable by cane.

The continuous traffic flow at roundabouts removes many of the audible cues that pedestrians who are blind use to navigate pedestrian street crossings. At roundabouts with multi-lane pedestrian street crossings, a pedestrian activated signal must be provided for each multilane segment of each crossing, including the splitter island (i.e., median island used to separate opposing directions of traffic entering and exiting a roundabout, MUTCD section 1A.13). Transportation officials who commented on the 2002 draft guidelines expressed concern that signalization of roundabouts would interfere with the flow of traffic at roundabout intersections. Pedestrian Hybrid Beacons can be used at roundabouts. See MUTCD sections 4F.01 through 4F.03. Pedestrian Hybrid Beacons are traffic signals that consist of a yellow signal centered below two horizontally aligned red signals. The signals are normally dark (i.e., not illuminated). The signals are initiated only upon pedestrian activation and can be timed to minimize the interruption of traffic. The signals cease operation after the pedestrian clears the crosswalk. When activated by a pedestrian, the following signals are displayed to drivers: a flashing yellow signal, then a steady yellow signal, then two steady red signals during the pedestrian walk interval, and then alternating flashing red signals during the pedestrian clearance interval. The following signals are displayed to pedestrians: a steady upraised hand (symbolizing DON’T WALK) when the flashing or steady yellow signal is operating, then a walking person (symbolizing WALK) when the steady red signals are operating, and then a flashing upraised hand (symbolizing DON’T WALK) when the alternating flashing red signals are operating. Transportation officials may request permission from the Federal Highway Administration to experiment with alternative signals at roundabouts (see MUTCD section 1A.10).⁴¹

⁴¹The Federal Highway Administration has granted interim approval to Rectangular Flashing Rapid Beacons, which can be used at roundabouts. However, Rectangular Flashing Rapid Beacons do not provide positive indication to drivers to stop and positive indication to pedestrians that the walk interval has been actuated. Rectangular Flashing Rapid Beacons do not meet MUTCD standards for accessible pedestrian signals and pedestrian pushbuttons.

Multi-Lane Channelized Turn Lanes (Section-by-Section Analysis)

Pedestrian activated signals must be provided at pedestrian street crossings at multi-lane channelized turn lanes at roundabouts and other signalized intersections. The pedestrian activated signals must comply with MUTCD standards for accessible pedestrian signals and pedestrian pushbuttons.

Governmental Units Affected (Section-by-Section Analysis)

The requirement for pedestrian activated signals at roundabouts with multi-lane pedestrian street crossings will affect state and local transportation departments that construct new roundabouts with multi-lane pedestrian street crossings. The Volpe Center estimated that state and local transportation departments construct 27 new roundabouts with multi-lane pedestrian street crossings on an annual basis.⁴²

⁴²The Volpe Center used the roundabout database at: http://roundabout.kittelson.com/ to estimate the number of new roundabouts with multi-lane pedestrian street crossings that are constructed on an annual basis. During the five year period between 2005 and 2009, 435 new roundabouts were constructed, of which 117 were multi-lane. The data was adjusted for a small number of roundabouts that are listed in the database as having an “unknown” number of lanes and for roundabouts that do have any pedestrian facilities (i.e., sidewalks and pedestrian street crossings).

Costs to Provide Pedestrian Activated Signals at Roundabouts with Multi-Lane Pedestrian Street Crossings (Section-by-Section Analysis)

The Volpe Center estimated the cost to provide pedestrian activated signals at new roundabouts with multi-lane pedestrian street crossings to range from $90,000 to $230,000 per roundabout, and the total annual costs for requiring pedestrian activated signals at new roundabouts with multi-lane pedestrian street crossings to range from $2.4 million to $6.2 million.

Question 19. The Access Board seeks additional information on the number of roundabouts with multilane pedestrian street crossings that are newly constructed on an annual basis by state and local transportation departments, and the costs to provide pedestrian activated signals at newly constructed roundabouts with multi-lane pedestrian street crossings.

R307 Accessible Pedestrian Signals and Pedestrian Pushbuttons (See R209) (Section-by-Section Analysis)

In the 2005 draft of the proposed guidelines, the technical requirements for accessible pedestrian signals and pedestrian pushbuttons were contained in Chapter R3. The proposed guidelines reference MUTCD standards for accessible pedestrian signals and pedestrian pushbuttons in the scoping requirements at R209. This section heading is included in Chapter R3 of the proposed guidelines to notify readers who were familiar with the 2005 draft of the proposed guidelines where to find the requirements for accessible pedestrian signals and pedestrian pushbuttons. This section heading will not be included in the final guidelines.

R308 Transit Stops and Transit Shelters (Section-by-Section Analysis)

The technical requirements for transit stops and transit shelters are contained in R308 and adapt the technical requirements for transit facilities in the 2004 ADA and ABA Accessibility Guidelines to the public right-of-way.

Transit Stops (R308.1) (Section-by-Section Analysis)

Boarding and alighting areas at sidewalk or street level transit stops must be 2.4 meters (8 feet) minimum measured perpendicular to the street or highway, and 1.5 meters (5 feet) minimum measured parallel to the street or highway. The grade of the boarding and alighting area parallel to the street or highway must be equal to street or highway grade to the extent practicable. The grade of the boarding and alighting area perpendicular to the street or highway must not exceed 2 percent. Where transit stops serve vehicles with more than one car, boarding and alighting areas serving each car must comply with these requirements.

Boarding platforms at transit stops must be positioned to coordinate with vehicles to minimize the vertical and horizontal gaps. The slope of boarding platforms must not exceed 2 percent in any direction. Where boarding platforms serve vehicles operating on existing track or existing street or highway, the slope of the platform parallel to the track or street or highway is permitted to equal the grade of the track or street or highway.

The surfaces of boarding and alighting areas and boarding platforms must comply with the technical requirements for surfaces (see R302.7). Boarding and alighting areas and boarding platforms must be connected to streets, sidewalks, or pedestrian circulation paths by a pedestrian access route.

Transit Shelters (R308.2) (Section-by-Section Analysis)

Transit shelters must be connected by a pedestrian access route to boarding and alighting areas or boarding platforms. A clear space (see R404) must be provided entirely within the transit shelter. Where seating is provided within transit shelters, the clear space must be located either at the end of a seat, or not overlap the area within 460 millimeters (1.5 feet) from the front edge of the seat in order to not interfere with others using the seating. Environmental controls within transit shelters must be proximity actuated. Protruding objects within transit shelters must comply with the technical requirements for protruding objects (see R402).

The Access Board is considering whether to require a turning space in transit shelters. Transit shelter designs vary. Some transit shelters are enclosed on three or four sides, with an opening for ingress and egress. The turning space would be based on the 2004 ADA and ABA Accessibility Guidelines (see 304.3).⁴³  The turning space would be permitted to overlap the clear space within the transit shelter and the pedestrian access route, but would not be permitted to overlap the area within 460 millimeters (1.5 feet) from the front edge of seats in the transit shelter in order to not interfere with others using the seating. The portion of the turning space that does not overlap the clear space would be permitted to be outside the transit shelter.

Question 20. Comments are requested on whether a turning space should be required in transit shelters and what impact such a requirement would have on the design and placement of transit shelters?

⁴³The 2004 ADA and ABA Accessibility Guidelines require a turning space to be either a circular space 1.5 meters (5 feet) minimum in diameter, or a T-shaped space within a square with sides 1.5 meters (5 feet) minimum where the arms and base of the T-Shaped space are 915 millimeters (3 feet) minimum. Each arm of the T-shaped space must be clear of obstructions 305 millimeters (1 foot) minimum in each direction, and the base must be clear of obstructions 610 millimeters (2 feet) minimum. A circular space is permitted to include knee and toe clearance. A T-shaped space is permitted to include knee and toe clearance only at the end of either the base or one arm.

R309 On-Street Parking Spaces (Section-by-Section Analysis)

General (R309.1) (Section-by-Section Analysis)

The technical requirements for accessible on-street parking spaces are contained in R309 and adapt the technical requirements for accessible parking spaces in the 2004 ADA and ABA Accessibility Guidelines to the public right-of-way.

Parallel Parking Spaces (R309.2) (Section-by-Section Analysis)

Where the adjacent sidewalk or available right-of-way is more than 4.3 meters (14 feet) wide, an access aisle must be provided at street level for the entire length of each accessible parallel parking space. The access aisle must be 1.5 meters (5 feet) wide minimum and connect to a pedestrian access route. The access aisle must not encroach on the vehicular travel lane and comply with the technical requirements for surfaces (see R302.7). In alterations where the street or sidewalk adjacent to the parking spaces is not altered, an access aisle is not required provided the parking spaces are located at the end of the block face.

Where the adjacent sidewalk or available right-of-way is less than or equal to 4.3 meters (14 feet) wide, an access aisle is not required, but accessible parallel parking spaces must be located at the end of the block face.

Perpendicular and Angled Parking Spaces (R309.3) (Section-by-Section Analysis)

An access aisle must be provided at street level for the entire length of each accessible perpendicular or angled parking space. The access aisle must be 2.4 meters (8 feet) wide minimum to accommodate vans with lifts, and connect to a pedestrian access route. Two accessible parking spaces are permitted to share a common access aisle. The access aisle must be marked to discourage parking in the aisle and comply with the technical requirements for surfaces (see R302.7).

Curb Ramps and Blended Transitions (R309.4) (Section-by-Section Analysis)

Curb ramps or blended transitions must connect the access aisle serving each accessible on-street parking space to the pedestrian access route. Curb ramps are not permitted within the access aisle. Parking spaces at the end of block face can be served by curb ramps or blended transitions at the pedestrian street crossing. Detectable warning surfaces are not required on curb ramps and blended transitions that connect the access aisle to the sidewalk, including where the sidewalk is at the same level as the parking spaces, unless the curb ramps and blended transitions also serve pedestrian street crossings.

Parking Meters and Parking Pay Stations (R309.5) (Section-by-Section Analysis)

Operable parts of parking meters and parking pay stations that serve accessible on-street parking spaces must comply with technical requirements for operable parts in Chapter R4. Displays and information must be visible from a point located 1 meter (3.3 feet) maximum above the center of the clear space in front of the parking meter or parking pay station. At accessible parallel parking spaces, parking meters must be located at the head or foot of the space.

R310 Passenger Loading Zones (Section-by-Section Analysis)

The technical requirements for accessible passenger loading zones are the same as in the 2004 ADA and ABA Accessibility Guidelines. A vehicular pull-up space 2.4 meters (8 feet) wide minimum and 6.1 meters (20 feet) long minimum must be provided at accessible passenger loading zones. An access aisle must be provided at the same level as the vehicle pull-up space. The access aisle must be 1.5 meters (5 feet) wide minimum, extend the entire length of the vehicle pull-up space, and connect to the pedestrian access route. The access aisle must be marked to discourage parking in the aisle and comply with the technical requirements for surfaces (see R302.7).