�92.179 Trams, similar vehicles and systems
(a) New and used trams consisting of a tractor unit, with or without passenger accommodations, and one or more passenger trailer units, including but not limited to vehicles providing shuttle service to remote parking areas, between hotels and other public accommodations, and between and within amusement parks and other recreation areas, shall comply with this section. For purposes of determining applicability of 49 CFR 37.101, 37.103, or 37.105, the capacity of such a vehicle or "train" shall consist of the total combined seating capacity of all units, plus the driver, prior to any modification for accessibility.
This provision sets forth the basic scope of coverage of this section. The provisions are intended to cover the types of vehicles used to provide shuttle or tour service and which typically consist of a tractor unit, with or without seats for passengers, pulling one or more trailer units with passenger seats. These guidelines may also apply to certain amusement park rides which provide general circulation within an exhibit.
Sections 37.101, 37.103, and 37.105 of the DOT regulation refer to the different requirements for vehicles with capacities over 16, 16 or fewer, or fewer than 8 persons, depending whether the entity is primarily or not primarily engaged in the business of transporting people. Thus, an entity whose primary business is operating a tram which serves as a tour of historic battlefields has a higher threshold for accessibility requirements than a hotel, which is not primarily in the business of transporting people, but which operates a shuttle to a nearby amusement park. For the purposes of determining the capacity of the vehicle, all of the passenger seats, plus the driver, in the entire train (tractor and one or more trailers) are counted. Furthermore, the count is taken of the number of seats in the "standard" vehicle, prior to any removal or rearrangement of seats needed to accommodate wheelchair or mobility aid users.
(b) Each tractor unit which accommodates passengers and each trailer unit shall comply with Ё1192.25 and 1192.29. In addition, each such unit shall comply with Ё1192.23(b) or (c) and shall provide at least one space for wheelchair or mobility aid users complying with �92.23(d) unless the complete operating unit consisting of tractor and one or more trailers can already accommodate at least two wheelchair or mobility aid users.
This section requires that each tractor unit which accommodates passengers and each trailer unit must comply with the provisions which apply to buses and vans for doors, steps and thresholds (�92.25) and interior circulation, handrails and stanchions (�92.29).
In addition, each new trailer unit, or tractor unit which accommodates passengers, purchased or leased after October 6, 1991, must be accessible and have space and securement for at least one wheelchair or mobility aid unless the combined unit of tractor and trailer already can accommodate two wheelchair or mobility aid users.
For example, if an entity purchases a new tractor unit with passenger seats that can accommodate one wheelchair or mobility aid user, the next trailer unit purchased for that train must also accommodate one wheelchair or mobility aid user. Other trailer units would not need to be accessible. If, on the other hand, the new tractor unit could accommodate two wheelchair or mobility aid users, no new trailer units would need to be accessible. Moreover, if new trailer units are purchased for an existing tractor unit, each would need to be accessible until the train could accommodate at least two wheelchair or mobility aid users.
Sections 1192.23(b) and (c) cover access by lift or ramp, respectively, and section 1192.23(d) contains requirements for securement space and devices. For ease of reference, these specific sections are included below.
�92.23 Mobility aid accessibility
(b) Vehicle lift.
(1) Design load
The design load of the lift shall be at least 600 pounds. Working parts, such as cables, pulleys, and shafts, which can be expected to wear, and upon which the lift depends for support of the load, shall have a safety factor of at least six, based on the ultimate strength of the material. Nonworking parts, such as platform, frame, and attachment hardware which would not be expected to wear, shall have a safety factor of at least three, based on the ultimate strength of the material.
Most lift manufacturers and transit agencies have been using the design load of 600 pounds specified in �92.23(b)(1) for some time. It is the same as the California specification and the FTA-sponsored Guidelines Specifications issued in 1986.
While some responses to the proposed guidelines suggested increasing the design load, it should be pointed out that the design load does not represent the maximum load the lift is capable of supporting. The safety factors for the support components mean the lift cables, pulleys and shaft will support 3600 pounds and the platform, frame and attachment hardware must support 1800 pounds. Except for a suggestion that a 700 pound design load be required to accommodate persons with service dogs, no real justification has been provided for increasing the load. This design load is consistent with the definition of a "common wheelchair or mobility aid" which weighs 600 pounds or less when occupied.
Both the FTA-sponsored Guideline Specifications and some state codes specify a detailed test and certification procedure to help ensure reliability, maintainability and durability, including hydraulic hose burst pressure. The Board does not view these issues as directly related to accessibility design but rather operational considerations. The DOT rule requires accessibility equipment to be maintained and those factors which could affect maintainability should generally be included in bid specifications. Furthermore, the National Highway Traffic and Safety Administration (NHTSA) may issue a regulation on several safety aspects of accessibility equipment which may include some specific testing requirements. The Board views NHTSA as the more appropriate agency to deal with these issues and has not dealt with them in the guidelines.
The controls shall be interlocked with the vehicle brakes, transmission, or door, or shall provide other appropriate mechanisms or systems, to ensure that the vehicle cannot be moved when the lift is not stowed and so the lift cannot be deployed unless the interlocks or systems are engaged. The lift shall deploy to all levels (i.e., ground, curb, and intermediate positions) normally encountered in the operating environment. Where provided, each control for deploying, lowering, raising, and stowing the lift and lowering the roll-off barrier shall be of a momentary contact type requiring continuous manual pressure by the operator and shall not allow improper lift sequencing when the lift platform is occupied. The controls shall allow reversal of the lift operation sequence, such as raising or lowering a platform that is part way down, without allowing an occupied platform to fold or retract into the stowed position.
This provision is adapted from the FTA-sponsored Guideline Specification but generalized since it applies to a broader range of vehicles including vans which rarely have transmission or brake interlocks like large buses. Most large vehicles are specified with door interlocks which prevent the bus from moving when the door is open. Since the door must be open to operate the lift, the above provision would be satisfied. If an auxiliary door is provided exclusively for a lift or ramp, that door would also need to be interlocked. Alternatively, the lift or ramp itself could be provided with its own interlock system.
For vans and some small vehicles, the situation may be less straight forward. The "appropriate mechanisms or systems" might include some relatively simple electrical interlocks to prevent the lift from being deployed unless the interlock is engaged. For example, some vans have a switch in the shift lever collar which is activated when the lever is placed in the "park" position. Other vehicles have an instrument panel warning light which is activated when the parking brake is fully engaged as a reminder to release it before moving the vehicle. Either of these electrical functions could be tied into the lift electrical system (perhaps through a relay) so that it could not be operated unless the vehicle transmission were in park or the emergency brake engaged. For a manual ramp which has no electrical function, a door switch may be appropriate if the vehicle electrical system is tied to the door switch in some fashion that would not allow the vehicle to be moved unless the ramp were stowed. For example, in many vans, the lift is operated from an auxiliary battery so that the vehicle ignition switch can be turned off. It would be a relatively simple matter to wire the ignition switch through a relay to a switch on the lift or door which is activated when the platform is stowed or the door closed, preventing the ignition switch from being turned on until the lift is stowed. On the other hand, a flashing light or buzzer which is activated by the lift or open door is not sufficient since it could be ignored. The key operational criterion is that the vehicle cannot be moved while the lift or ramp is in use. The interlock mechanism or circuit may not be activated until the lift or ramp has moved some slight distance from its stowed position provided the interlock engages before any gaps occur which could pose a hazard. Generally, gaps between the platform and vehicle floor, for example, should not exceed 5/8 inch before the interlock engages.
Furthermore, the lift must be designed to deploy to all levels expected to be encountered in the operating environment. While generally not a problem with today's equipment, some older devices would not deploy to ground level unless the vehicle were first "kneeled". There are a few cases, however, where the device might not need to reach the ground. If, for example, the vehicle operates only along a restricted right-of-way such as a specially designed pedestrian mall where all of the stops are at raised curbs, or only stops at designated stations with raised platforms, then all stops encountered in the operating environment are above ground level.
One problem which has been encountered in some environments is that the curb is too high, rather than too low, for the lift. This also occurs when the road has a high crown, tipping the bus toward the curb. The problem is especially acute for front door lifts. At least one transit operator with front door lifts has specified a "kneeling" air bag on the left rear wheel. Lowering the left rear suspension raises the front right corner, thus leveling the bus, allowing the lift to be deployed. While this is not a requirement, it is worth considering for inclusion in new vehicles.
Finally, the controls must be of the momentary contact type, requiring continuous pressure to activate and must be interlocked to preclude the possibility of folding or stowing the lift when the platform is occupied (except as provided in the exception discussed below). Some lifts currently in service can be folded or stowed simply because the operator presses the wrong button at the wrong time. This regulatory provision is intended to preclude this possibility. Some lifts accomplish this function by incorporating a pressure sensitive switch in the platform to sense when it is occupied. Others incorporate a slip-clutch mechanism on the folding motor such that it is not capable of folding anything heavier than an empty platform. Photocells or proximity switches might also be employed to detect the presence of a person on the lift platform. Some lifts also employ pressure switches at pinch points to stop the lift operation if a passenger's foot is caught between opposing members. Whatever system is used, it should be designed so that, if the pressure switch, photocell or proximity switch is not operating, the lift will not operate.
The lift must be capable of reversal, but without folding or stowing. For example, if the platform is raised to the bus floor but the inner barrier fails to retract to allow the user to board, then the controls must allow the lift to be returned to the ground level for deboarding. In this case, the fold or stow function must still be precluded until the platform is empty.
Where the lift is designed to deploy with its long dimension parallel to the vehicle axis and which pivots into or out of the vehicle while occupied (i.e., "rotary lift"), the requirements of this paragraph prohibiting the lift from being stowed while occupied shall not apply if the stowed position is within the passenger compartment and the lift is intended to be stowed while occupied.
This provision simply permits the use of a certain type of lift which would be precluded by the previous requirement that the lift cannot be stowed when occupied. The particular type of device, a rotary lift, intended to be covered by this exception is one in which the platform rotates into the vehicle and this is the stowed position. In this case, the lift is intended to be stowed while occupied, which would otherwise be prohibited by strict application of the previous paragraph. It should be noted, however, that another type of rotary lift in which the platform is intended to be raised to a vertical position for stowage, is not covered by this exception. Such a design is not precluded, since the rotation of the platform while occupied is not prohibited, but the actual raising of the platform into the vertical stowed position must still be prevented when the platform is occupied.
(3) Emergency operation
The lift shall incorporate an emergency method of deploying, lowering to ground level with a lift occupant, and raising and stowing the empty lift if the power to the lift fails. No emergency method, manual or otherwise, shall be capable of being operated in a manner that could be hazardous to the lift occupant or to the operator when operated according to manufacturer's instructions, and shall not permit the platform to be stowed or folded when occupied, unless the lift is a rotary lift and is intended to be stowed while occupied.
This provision is intended to allow persons who need the lift to deboard, to do so even if the lift or bus power fails. Typically, this operation is performed by a hand operated crank or pump, although some devices incorporate a back-up power system. The emergency system is only intended to allow the lift to be deployed and lowered to the ground with an occupant, not to allow the passenger to board the vehicle. Whatever method is used for
emergency operation, it must continue to operate safely, when operated according to manufacturer's instructions. The emergency system must not permit the lift to be stowed or folded when occupied. This could be accomplished with a pressure valve in the hand pump system which would not allow sufficient pressure to fold a lift platform which had some specific weight on it. Another possible way to comply with this provision is to provide two separate pump control systems, one for raising and lowering and one for stowing, which require a hand lever to be removed from one valve and placed in another to allow operation. This could be especially effective if the stowage control access point were physically blocked by a lift occupant.
(4) Power or equipment failure
Platforms stowed in a vertical position, and deployed platforms when occupied, shall have provisions to prevent their deploying, falling, or folding any faster than 12 inches/second or their dropping of an occupant in the event of a single failure of any load carrying component.
This provision requires some sort of "braking" or "damping" mechanism, similar to those provided on elevators, to prevent "free fall" of an occupied platform in the event of a power failure or single failure of any load carrying component. The fall rate is substantively the same as the FTA-sponsored Guideline Specifications. The provision applies to the fall rate of the deployment cycle as well as an occupied lift platform because it is also intended to protect a person with a disability who might be waiting close to the vehicle for the lift to deploy when the power fails. This is not a "planned" event which can be anticipated and the slow rate might provide enough time to move out of the way. This provision applies only to those lifts which are stowed in a vertical position, generally the so-called "active" lifts, which could unfold when someone is waiting outside the vehicle. Most such lifts with a powered deploy cycle simply stop when the power fails. Preventing rapid deployment in the event of a single failure of a load carrying component, such as a chain or cable breakage, will require more ingenuity.
(5) Platform barriers
The lift platform shall be equipped with barriers to prevent any of the wheels of a wheelchair or mobility aid from rolling off the platform during its operation. A movable barrier or inherent design feature shall prevent a wheelchair or mobility aid from rolling off the edge closest to the vehicle until the platform is in its fully raised position. Each side of the lift platform which extends beyond the vehicle in its raised position shall have a barrier a minimum 1-1/2 inches high. Such barriers shall not interfere with maneuvering into or out of the aisle. The loading-edge barrier (outer barrier) which functions as a loading ramp when the lift is at ground level, shall be sufficient when raised or closed, or a supplementary system shall be provided, to prevent a power wheelchair or mobility aid from riding over or defeating it. The outer barrier of the lift shall automatically raise or close, or a supplementary system shall automatically engage, and remain raised, closed, or engaged at all times that the platform is more than 3 inches above the roadway or sidewalk and the platform is occupied. Alternatively, a barrier or system may be raised, lowered, opened, closed, engaged, or disengaged by the lift operator, provided an interlock or inherent design feature prevents the lift from rising unless the barrier is raised or closed or the supplementary system is engaged.
The first part of this provision covers the barrier (often called a "roll stop") which is intended to prevent the lift user from rolling or stepping off the platform edge closest to the vehicle. Some lifts have a flap which rises when the lift is deployed and lowers when the platform reaches the vehicle floor level. Other designs depend on the structure of the vehicle itself or a "close-out panel" to prevent falling off the inner edge. This feature is particularly important in some van applications where a persons' toes can be trapped between the rising lift platform and the underside of the door sill (as explained later, the lift must be designed to accommodate both inward and outward facing of wheelchair and mobility aid users).
Clarifying language has also been added to the provision with regard to the meaning of "entering the vehicle" and the need for side barriers on the portion of the lift which is outside the vehicle when the platform is raised. That is, the portion of the lift platform which remains outside the vehicle when the lift is in the raised position must have side barriers. The portion which is inside the vehicle envelope does not need side barriers, since such barriers could restrict the ability of a wheelchair or mobility aid user in turning into the aisle. In addition, a specific prohibition makes it clear that the side barriers cannot interfere with maneuvering. Care must be taken in this design because there is often a gap between the side of the lift platform and the bus floor when the lift is fully raised. Several lift manufacturers and transit operators use various "close-out" gaskets and devices to eliminate or reduce such gaps so that the wheel of a wheelchair or mobility aid will not be trapped when it turns into the aisle. The height requirement for side barriers has been chosen to accommodate some rims on the cambered wheels of sport wheelchairs which may need space to clear the barriers. Higher barriers might interfere with such chairs unless the platform is wider.
With respect to the requirement for the loading edge (outer) barrier, consideration was given to both a general performance requirement and a more specific requirement for application of a specified force at a specified height. Many transit agencies and lift manufacturers had suggested that the test procedure for outer edge barriers in the FTA-sponsored Guideline Specifications be included in �92.23(b)(5). This test procedure involved the use of actual wheelchairs being driven against outer barriers in order to determine the minimum height and strength for a barrier which would prevent a wheelchair from rolling off the lift platform. The Board also considered suggestions to set a maximum barrier height ranging from 2 inches to 6 inches and to require that the barrier angle outward at 45 degrees to accommodate larger wheelchairs.
The Board has not specified a safety test for the loading edge (outer) barrier in the final guidelines because NHTSA may issue proposed safety standards for lifts. The Board feels that NHTSA is the appropriate agency to define safety tests. In the meantime, �92.23(b)(5) includes only a performance requirement. The detailed force test in the original proposal could have been interpreted as meaning that a 3-inch high barrier was sufficient to prevent a power wheelchair from rolling off a platform. This is not the case, since some common power wheelchairs can easily ride over a 3-inch barrier, even if it is firmly locked in its raised position. A barrier with a height greater than 3 inches may be adequate, depending on the angle of the barrier and its rigidity, but a specific test has not been performed to determine what the appropriate height should be. Further, the proposed test seemed to ignore other potential solutions such as a reported Canadian standard which would address the issue of preventing the occupant of a wheelchair or mobility aid from falling from the platform in addition to restraining the chair. Accordingly, the final provision permits a supplementary system as an alternative to a high barrier.
Finally, whatever barrier or supplemental system is used, it must either rise or engage automatically when the lift is raised more than three inches off the ground, or there must be an interlock which prevents the lift from rising more than three inches off the ground unless the barrier or supplementary system is engaged. Thus, the barrier or system could be engaged manually, provided the lift could not rise unless it were properly engaged. Systems could employ an electrical switch which interrupts power to the lift unless the barrier is engaged or might use a mechanical slip-clutch or gear and sprocket arrangement which is engaged only when the barrier is raised or the supplemental system is engaged.
(6) Platform surface
The platform surface shall be free of any protrusions over 1/4 inch high and shall be slip resistant. The platform shall have a minimum clear width of 28-1/2 inches at the platform, a minimum clear width of 30 inches measured from 2 inches above the platform surface to 30 inches above the platform, and a minimum clear length of 48 inches measured from 2 inches above the surface of the platform to 30 inches above the surface of the platform. (See Fig. 1)
The 30 inch by 48 inch platform is consistent with accessibility requirements which have been in effect since 1980. The Board acknowledges that some power wheelchairs cannot be accommodated on such a platform but does not have sufficient data on which to base a requirement for a larger platform although some manufacturers and transit operators had suggested that the platform length be 50 inches. Lift platforms which exceed the minimum requirements of this section are desirable to accommodate a larger proportion of the potential population. Such lifts are, in fact, commercially available. The minimum platform size applies to both large and small vehicles since they will need to serve the same population in most cases.
The FTA-sponsored Guideline Specifications called for a platform length of only 44 inches, 2-1/2 inches above the platform, although 48 inches was recommended. This shorter length included in the FTA-sponsored Guideline Specifications was based on incomplete data and would not accommodate larger power wheelchairs and three wheeled scooters which are used by many individuals with disabilities who ride public transportation. These data were derived from the length of the wheelchair itself rather than the length of a wheelchair and its user.
On the other hand, UFAS and the ANSI A117.1-1980 standards specify a 48 inch length for an occupied wheelchair and require a space of 48 inches by 30 inches for the clear floor space required to accommodate a single stationary wheelchair and for a platform lift. A diagram in the appendix of the 1980 ANSI standard clearly shows that the toes of a wheelchair occupant extend four to six inches beyond the footplates. Furthermore, power wheelchairs usually have "anti-tip bars" behind and below the curve of the rear wheels and smaller rear wheels that are set further back than manual wheelchairs and which limit the location of lift safety barriers. This information has been readily available for some time, and was discussed at length in the Board's technical publication Lifts and Wheelchair Securement published in 1987. Most lift manufacturers have responded to this information and have designed their lifts accordingly.
Section 1192.23(b)(6) is consistent with the definition of common wheelchairs and mobility aids and provides that the 48 inch length and 30 inch width are to be measured 2 inches above the platform. The reason for the length measurement to be taken at the 2-inch height is to allow for certain elements such as barrier hinges or control rods to impinge on the 48-inch envelope only if they do not interfere with anti-tip bars and other parts of the wheelchair or mobility aid. While a minimum length at the platform surface is not specified (unlike the width requirement) obviously the platform surface cannot be less than the wheelbase of the mobility aid.
The width measurement acknowledges that the door structure of some buses would not permit a 30 inch wide platform unless the door or vehicle frame were modified. This section allows the width to be measured 2 inches above the platform to allow a narrower platform at the bottom only, thus permitting wider lifts to be incorporated without the need to modify the door frame. Also, the lift handrails are often attached to the platform at the bottom and the structural material takes up some portion of the usable surface. In order to achieve a platform with a clear width of 30 inches at the surface would require a lift with a much wider overall width. Measuring the width above the handrail anchor points allows a lift which does not affect door structure but still allows a clear 30 inches between handrails. The clear space is measured to a height of 30 inches to clear the armrests of most wheelchairs and mobility aids. The clear space required is shown as the shaded portion of Figure 1. In effect, a box of the indicated dimensions must be accommodated on the platform. The barriers must not intrude into this area when raised. Thus, the inner roll stop and outer barriers must be vertical or, preferably slant outward, to provide the clear area. Under no circumstances may the barriers slant inward into the required clear space.
The requirement for the 1/4-inch maximum protrusion is consistent with common accessibility standards, such as UFAS and ANSI, and is intended to reduce tripping hazards for standees.
The requirement for slip resistance is a general performance requirement. The Board had considered using a measure of the static coefficient of friction to determine slip resistance but the practical difficulties of defining an appropriate test procedure convinced the Board that a specific requirement should not be imposed.
The appendix notes that slip resistance is based on the frictional force necessary to keep a shoe heel or crutch tip from slipping on a walking surface under conditions likely to be found on the surface. While the dynamic coefficient of friction during walking varies in a complex and non-uniform way, the static coefficient of friction, which can be measured in several ways, provides a close approximation of the slip resistance of a surface. Contrary to popular belief, some slippage is necessary for walking, especially for persons with restricted gaits; a truly "non-slip" surface could not be negotiated.
The Occupational Safety and Health Administration recommends that walking surfaces have a static coefficient of friction of 0.5. A research project sponsored by the Board conducted tests with persons with disabilities and concluded that a higher coefficient of friction was needed by such persons. A static coefficient of friction of 0.6 is recommended for steps, floors, and lift platforms and 0.8 for ramps.
The coefficient of friction varies considerably due to the presence of contaminants, water, floor finishes, and other factors not under the control of transit providers and may be difficult to measure. Nevertheless, many common materials suitable for flooring or lift platform surfaces are now labeled with information on the static coefficient of friction. While it may not be possible to compare one product directly with another, or to guarantee a constant measure, transit operators or vehicle designers and manufacturers are encouraged to specify materials with appropriate values. As more products include information on slip resistance, improved uniformity in measurement and specification is likely. The Access Board's advisory guidelines on Slip Resistant Surfaces, available from the Board at no cost, provides additional information on this subject.
(7) Platform gaps
Any openings between the platform surface and the raised barriers shall not exceed 5/8 inch in width. When the platform is at vehicle floor height with the inner barrier (if applicable) down or retracted, gaps between the forward lift platform edge and the vehicle floor shall not exceed 1/2 inch horizontally and 5/8 inch vertically. Platforms on semi-automatic lifts may have a hand hold not exceeding 1-1/2 inches by 4-1/2 inches located between the edge barriers.
This section is intended to prevent the front caster of a wheelchair from turning sideways and dropping through the gap between the raised barrier and the platform. It is the quantification of a performance criterion because 5/8 inch is the approximate width of a wheelchair caster wheel. It should also be small enough to prevent a service dog paw from falling through. The provision applies only to the gap between the platform and the raised barrier and does not preclude the use of expanded metal platforms.
The proposed guidelines had separate subparts for buses and vans. The provision for a hand-hold in the platforms of semi-automatic lifts has been moved to �92.23(b)(7) in the final guidelines since the two previous subparts have been combined.
(8) Platform entrance ramp
The entrance ramp, or loading-edge barrier used as a ramp, shall not exceed a slope of 1:8, measured on level ground, for a maximum rise of 3 inches, and the transition from roadway or sidewalk to ramp may be vertical without edge treatment up to 1/4 inch. Thresholds between 1/4 inch and 1/2 inch high shall be beveled with a slope no greater than 1:2.
In most lift designs, the outer barrier folds down to form a ramp up onto the platform. The ramp slope in this section is based on common accessibility standards. The Board is inclined to relax certain slope standards where there is reason to do so, based on physical constraints. However, in view of the availability of equipment which meets the requirements of this section, and the lack of convincing evidence that the slope should be changed, the requirement has been retained. A suggestion to define the slope as being measured on level ground has been incorporated.
In general, the leading edge of the ramp must be tapered. A maximum vertical edge of 1/4 inch is permitted but, if the lip is 1/4 inch to 1/2 inch, the edge must be beveled to a slope of 1:2. In no case may the lip be greater than 1/2 inch high.
(9) Platform deflection
The lift platform (not including the entrance ramp) shall not deflect more than 3 degrees (exclusive of vehicle roll or pitch) in any direction between its unloaded position and its position when loaded with 600 pounds applied through a 26 inch by 26 inch test pallet at the centroid of the platform.
The FTA-sponsored Guideline Specifications provide for a 400 pound test for active lifts commonly used on small buses and vans and a 600 pound test load for passive lifts commonly used on large buses. During rulemaking, the Board considered whether the smaller load should be applied to active lifts.
The provision has been clarified so that the platform deflection is exclusive of vehicle roll or pitch. The exclusion of vehicle roll is to account for the case in which the lift is installed in a side door and the exclusion of pitch is for the case where an active lift may be located in the rear door of a van or small bus. In practice, however, the Board expects that the deflection would not be measured on the vehicle but would be measured by the manufacturer on a "test rig" in the factory. The manufacturer would then certify the lift as meeting the requirement. The same is also anticipated for other measures, such as acceleration and barrier resistance.
Since the vehicle will normally tilt when the lift is loaded, due to the weight of the wheelchair or mobility aid and the user, there will be a slope away from the vehicle toward the barrier. The reason for limiting the deflection of the lift platform is to minimize the contribution to this slope by the platform itself. This provision has been a part of the FTA-sponsored Guideline Specifications for passive lifts. The reason for not changing the deflection load is that the lift must function when occupied by a common wheelchair or mobility aid which is defined as weighing as much as 600 pounds when occupied. To increase the angle would allow the platform to slope more with a heavy wheelchair, a situation which is potentially the most dangerous and the most likely to result in a wheelchair or mobility aid overriding or defeating the outer barrier.
With respect to active lifts typically used on vans and small vehicles, the vehicle roll is even more pronounced due to the lighter vehicle weight and less stiff suspension. In reality, such lifts should be required to have less deflection, not more, to compensate for the greater vehicle roll. However, stricter requirements on these lifts is not required at this time. It should be noted that, under the ADA, persons who could use a fixed route bus, but the route needed is not yet accessible, are eligible for paratransit. Therefore, it makes no sense for the vehicles providing such demand responsive service to meet a lesser requirement than those for fixed route buses. They both must accommodate the same range of common wheelchairs and mobility aids. The test pallet defined is approximately the width of a typical wheelchair or mobility aid wheelbase and the length is the average between a common three-wheel scooter and a common power wheelchair. The platform centroid, or center of mass, will usually be close to the geometric center of the platform.
(10) Platform movement
No part of the platform shall move at a rate exceeding 6 inches/second during lowering and lifting an occupant, and shall not exceed 12 inches/second during deploying or stowing. This requirement does not apply to the deployment or stowage cycles of lifts that are manually deployed or stowed. The maximum platform horizontal and vertical acceleration when occupied shall be 0.3g.
The requirements in this section are taken directly from the FTA-sponsored Guideline Specifications which adopted a speed slower than some other specifications for reasons of safety and comfort. The slower speed is even more important for use by standees. However, the slower speed is primarily relevant to the raising and lowering of an occupied lift. The Board is concerned about unnecessarily increasing dwell time. Nevertheless, the speed with which the lift deploys or stows is not unrelated to safety. A potential user waiting outside the vehicle might not be able to get out of the way of a rapidly deploying lift. Similarly, some lifts which fold up into the passenger compartment, particularly active lifts, could pose a hazard to a person inside the vehicle near the lift if the platform is stowed too fast. Accordingly, the final rule provision specifies the 6 inch per second speed only for the raising and lowering of an occupied lift and a 12 inch per second speed for the deploy and stow portion of the cycle.
The FTA-sponsored Guideline Specifications specify an acceleration rate of 0.3g for active lifts and 0.2g for passive lifts. A lower rate was specified for passive lifts for reasons of comfort, even though an earlier report on lift safety had recommended a rate of 0.3g. The Advisory Panel which developed the FTA-sponsored Guideline Specifications did not examine, nor is the Board aware of, any evidence that the higher acceleration rate permitted for active lifts is unsafe or uncomfortable for passive lifts. Since the requirements for large and small buses and vans have been consolidated, the final guidelines specify the 0.3g acceleration rate.
The Board considered a requirement for the maximum rate of change of acceleration (jerk) but did not do so because it is difficult to measure and can be affected by other variables not directly related to the rate of change of acceleration of the lift platform itself. Also, there is no research which identifies acceptable rates for persons with disabilities.
(11) Boarding direction
The lift shall permit both inboard and outboard facing of wheelchair and mobility aid users.
This provision is taken directly from the Guideline Specifications and is straightforward. While some operators advise wheelchair or mobility aid users to back onto the lift, it is difficult for some persons to do so. Backward maneuvering past the fare box and into the aisle of a front door lift bus is especially problematic for some people. Therefore, the lift must permit persons to board and alight facing either in toward the vehicle or out toward the sidewalk or boarding area. This requirement should be considered in conjunction with the barrier or supplemental system designed to retain the wheelchair or mobility aid on the platform. For example, some barriers have been designed to rise under the curve of the rear wheel or under the front footrests of a wheelchair. Some designs may be usable only if the occupant is facing a particular direction. This is not permitted. Similarly, at least one supplementary lift restraint system used in Canada involves a belt connected between handrails. In some configurations, the belt is intended to be fastened around the front of the wheelchair when the wheelchair is facing outward. Since the lift must accommodate both inward and outward facing wheelchairs and mobility aids, the belt would need to be long enough to go around the back of the wheelchair or mobility aid if the person is facing inward.
(12) Use by standees
Lifts shall accommodate persons using walkers, crutches, canes or braces or who otherwise have difficulty using steps. The platform may be marked to indicate a preferred standing position.
The requirement in this section regarding use by standees received wide support from all commenters to the proposed rule, including APTA and two other transit organizations, individuals with disabilities and their organizations, government agencies concerned with accessibility, and consultants. Similar support was expressed for the same requirement with respect to vans and small buses.
The legislative history of the ADA clearly states that Congress intended lifts to accommodate standees. See H. Rept. 101-485, pt. 2, at 89. In view of the wide support for this provision, including transit operators and transit associations, the Board has retained the requirement in the final guidelines. The DOT rule requires that operators accommodate standees on lifts which meet the design requirements of Part 38. Some current lifts already meet those standards with respect to standees, providing handrails which move in tandem with the lift, and several transit systems have accommodated standees on lifts for several years with no reported problems. See 49 CFR 37.165(g).
There has been some consideration to providing contrasting marking around the perimeter of the platform. Some standards do specify such marking. In light of the other requirements for lighting on the platform, a contrasting edge, side barriers, and handrails, the Board does not believe that a perimeter marking should be required.
Platforms on lifts shall be equipped with handrails on two sides, which move in tandem with the lift, and which shall be graspable and provide support to standees throughout the entire lift operation. Handrails shall have a usable component at least 8 inches long with the lowest portion a minimum 30 inches above the platform and the highest portion a maximum 38 inches above the platform. The handrails shall be capable of withstanding a force of 100 pounds concentrated at any point on the handrail without permanent deformation of the rail or its supporting structure. The handrail shall have a cross-sectional diameter between 1 1/4 inches and 1 1/2 inches or shall provide an equivalent grasping surface, and have eased edges with corner radii of not less than 1/8 inch. Handrails shall be placed to provide a minimum 1 1/2 inches knuckle clearance from the nearest adjacent surface. Handrails shall not interfere with wheelchair or mobility aid maneuverability when entering or leaving the vehicle.
The 100 pound force requirement for lift handrails is derived from the Canadian and the California standards. Handrails and grab bars in buildings and facilities are required to withstand a force of 250 pounds and the White Book generally requires bus handrails to meet a 300 pound test. However, the Canadian standard is well established and the Board believes it should not be changed without evidence that it is inadequate.
With respect to the force requirements, handrails in buildings and facilities are required to withstand much higher forces because they are intended to provide support for rising from a sitting position, maneuvering into and out of a wheelchair or mobility aid, or walking up or down stairs or ramps. The handrails on a lift are intended only to provide stability as opposed to major support. Lift handrails meeting the 100 pound force requirement have been in service for many years with no known problem. Moreover, handrails mounted on walls, are subject to torques which are very different from those on lift handrails attached only to the platform. To withstand equivalent forces would require substantial reinforcement of the lift handrail attachment points, with corresponding increases in weight, and a potential decrease in the platform width. In the absence of information that the 100 pound force requirement is inadequate, it has not been changed.
As for handrail shape, the configuration is related to mounting height. For example, the FTA-sponsored Guideline Specifications specify mounting between 25 inches and 34 inches. Considerable research has been conducted in the past on the height of a handrail which can be used by persons with a disability. Until recently, the accepted height has been a minimum 30 inches and a maximum 34 inches above the platform. More recent research on handrail height has suggested that a height from 34 inches to 38 inches is better and these dimensions have been accepted by the model building codes and incorporated in the Board's final guidelines for buildings and facilities. Because of design constraints imposed by the vehicle, the Board is not inclined to impose these new dimensions on lift handrails. However, some entities have suggested a higher upper limit than the original proposal, so the Board has incorporated the 38 inch maximum but retained the 30 inch minimum height in this section. Consideration was given to establishing a performance criterion instead of height requirements, but the existence of such criteria currently has resulted in the placement of handrails which are too low, according to research. Clearly, specific guidance is needed to correct this situation.
With respect to handrail shape or configuration, the Board is not aware of any problems with either curved or vertical handrails, provided they move in tandem with the platform. Therefore, the provision contains no explicit reference to diagonal or horizontal configuration.
The proposed rule would have required the handrail to have a horizontal or diagonal component, at least 12 inches long, at the appropriate height. However, the usable length has been changed from 12 inches to 8 inches so that a vertical handrail between the mounting height limits would not be precluded. Handrails which extend above or below the limits are permitted, provided a usable segment is provided within the limits.
As for handrail diameter, the requirements in this section are consistent with the White Book. Also, the Board-sponsored Hand Anthropometrics research project tested gripping by persons with various hand disabilities and confirmed the appropriateness of the specified dimensions. A 1-inch diameter handrail would not be usable. The Board notes that most vehicle handrails are made of pipe. In the building industry, pipe size typically specifies inside diameter so that a 1-1/2 inch pipe handrail actually has a larger outside diameter, sometimes up to 2 inches. Such handrails have not posed any known problem. Thus, the 1-1/2 inch diameter requirement can result in a handrail of almost 2 inches under current building industry practices. The 1-1/2 inch clearance also received general support and has been included.
It is critical that more than one handrail be provided if standees are to be able to use the lift. The presence of two handrails is also critical for rotary lifts. However, because of the design of rotary lifts, it may be that a suitable configuration can be achieved with handrails that are not necessarily on opposite sides of the platform, but might be on two adjacent sides. Accordingly, this section specifies handrails on "two sides" rather than "both sides" of the platform. The performance criterion that the handrails be usable throughout the entire lift cycle still applies.
(c) Vehicle ramp
(1) Design load
Ramps 30 inches or longer shall support a load of 600 pounds, placed at the centroid of the ramp distributed over an area of 26 inches by 26 inches, with a safety factor of at least 3 based on the ultimate strength of the material. Ramps shorter than 30 inches shall support a load of 300 pounds.
The Guideline Specifications, from which most of the technical requirements for ramps were drawn, specifies only a 400 pound design load for ramps, based primarily on the small market identified at the time those guidelines were developed. However, since ramps are permitted in some cases instead of lifts, it is essential that they be designed to accommodate the same range of common wheelchairs and mobility aids. Therefore, the 600 pound design load has been specified for ramps of 30 inches or longer.
For ramps or bridge plates which are approximately the length of the specified test pallet, placing a loaded pallet on the ramp would not test the strength of the ramp but would instead merely rest on the vehicle and platform or curb. Furthermore, ramps shorter than 30 inches need support only about half the weight of a wheelchair or other mobility aid at a given point: when the front wheels are on the ramp, the rear wheels are still on the sidewalk or boarding area, and when the rear wheels move onto the ramp, the front wheels will be inside the vehicle. Therefore, a 300 pound design load is specified for shorter ramps. The provision does not specify a test pallet for making this measurement, but manufacturers should use a method which approximates the loading that would be expected from either the front or rear wheels of a wheelchair or mobility aid, applied at enough points along the ramp length to ensure that it will support a common wheelchair or mobility aid user without significant deflection.
(2) Ramp surface
The ramp surface shall be continuous and slip resistant; shall not have protrusions from the surface greater than 1/4 inch high; shall have a clear width of 30 inches; and shall accommodate both four-wheel and three-wheel mobility aids.
The term "continuous surface" is used instead of "solid surface" to mean a single, uninterrupted surface from edge to edge as opposed to a platform with a gap in the middle that may incorporate steps. It is also intended to preclude the use of two separate ramps placed some distance apart. Those configurations can accommodate four wheeled devices but cannot accommodate three wheeled scooters. Ramps having two parts are permitted, provided they are designed to be deployed together to provide a uniform, uninterrupted surface. The term is not intended to preclude expanded metal ramps which are often much lighter than solid platforms of the same strength.
While lift platforms are permitted to be 28-1/2 inches wide, ramps must have a clear width at the surface of 30 inches. This is because ramps are designed to be traversed, while a wheelchair or mobility aid user essentially remains stationary on a lift platform while it is in operation. For this reason, a wheelchair or mobility aid user needs more clearance on a ramp for maneuvering than on a lift platform. The restriction on 1/4-inch high protrusions is taken from common accessibility standards for accessible surfaces.
The Board had considered specifying a value of 0.8 for the static coefficient of friction as a measure of slip resistance. Due to the practical difficulties in specifying an easily measured value, there is no specific requirement for a coefficient of friction. The Board has included advisory information in the appendix to the guidelines and a technical assistance brochure "Slip Resistant Surfaces" is available from the Board at no cost. See the discussion of slip resistance under section 1192.23(b)(6) above.
(3) Ramp threshold
The transition from roadway or sidewalk and the transition from vehicle floor to the ramp may be vertical without edge treatment up to 1/4 inch. Changes in level between 1/4 inch and 1/2 inch shall be beveled with a slope no greater than 1:2.
This provision is drawn from common accessibility requirements for accessible ground and floor surfaces. The ends of the ramp, both where it meets the roadway, sidewalk or boarding area, and the transition to vehicle floor, must be tapered to 1/4 inch vertical lip or up to 1/2 inch, beveled to a slope of 1:2. In no case may the lip exceed 1/2 inch.
Since the requirement is based on common accessibility standards and ramp manufacturers said that it was easily achievable, the Board has not changed the provision. Operators who suggested a 5/8 inch threshold seemed to have been concerned about existing equipment which is not affected by these guidelines.
(4) Ramp barriers
Each side of the ramp shall have barriers at least 2 inches high to prevent mobility aid wheels from slipping off.
Some responses to the original proposal suggested that the height of side barriers should depend on the length of the ramp. One operator uses a short bridge plate placed between door posts which, in its view limits lateral movement of a wheelchair or mobility aid to the extent that side barriers are unnecessary.
The Board has no information which provides a rationale on how the barriers should vary according to ramp length. While short ramps or bridge plates that are placed between door posts limit the likelihood of a wheelchair or mobility aid rolling off, the Board believes there is still sufficient danger in many situations to require edge barriers. In the absence of any data on what the cutoff point should be, and in view of limited opposition to the provision, the Board has decided not to change this requirement until further study is completed or additional information is obtained. The Board will consider adding additional requirements during future revisions and updates of the guidelines.
The height requirement for side barriers on ramps is derived from common accessibility requirements for ramps. The height differs from that for lift platform side barriers because wheelchairs and mobility aids move along the ramp during boarding and alighting and there is substantially more opportunity for wheels to ride over the barriers than for lift platforms.
Ramps shall have the least slope practicable and shall not exceed 1:4 when deployed to ground level. If the height of the vehicle floor from which the ramp is deployed is 3 inches or less above a 6-inch curb, a maximum slope of 1:4 is permitted; if the height of the vehicle floor from which the ramp is deployed is 6 inches or less, but greater than 3 inches, above a 6-inch curb, a maximum slope of 1:6 is permitted; if the height of the vehicle floor from which the ramp is deployed is 9 inches or less, but greater than 6 inches, above a 6-inch curb, a maximum slope of 1:8 is permitted; if the height of the vehicle floor from which the ramp is deployed is greater than 9 inches above a 6-inch curb, a slope of 1:12 shall be achieved. Folding or telescoping ramps are permitted provided they meet all structural requirements of this section.
Tests of ramps on buses were conducted as part of the Transbus program. Those tests showed that a slope of 1:6 was generally the maximum slope which could be negotiated but that short ramps of 1:4 slope could be used by some persons under some circumstances. The Board recognizes that there are practical difficulties in meeting common accessibility standards in vehicles which are constrained by other factors, such as maximum width. Further, some ramped buses designed for and used in urban areas would have ramp slopes at curbs which meet common accessibility standards but may also operate under other conditions, such as rural areas. Nevertheless, because of the advantages of ramped buses in terms of cost, efficiency and speed of boarding, the Board does not want to preclude their use or continued development.
In view of the factors which could affect ramp slope, the proposed section was revised. The final provision requires that, in general, the least slope practicable be obtained, and may not exceed 1:4 when deployed to the ground. For purposes of determining the "normal" deployment condition, the provision assumes a 6 inch high curb. A slope of 1:4 is permitted if the vertical floor height is 3 inches or less above a 6 inch curb. This would require a ramp approximately 1 foot long and would be short enough to be negotiable by many people. If the floor height does not exceed 6 inches above the curb, a slope of 1:6 would be permitted. A slope of 1:8 would be permitted if the floor height does not exceed 9 inches above the 6 inch curb. A slope of 1:12 would be required for greater rises.
|Height of Vehicle Floor Above 6-inch Curb||Maximum Ramp Slope|
|3 in. or less||1:4|
|6 in. or less but more than 3 in.||1:6|
|9 in. or less but more than 6 in.||1:8|
|more than 9 in.||1:12|
When in use for boarding or alighting, the ramp shall be firmly attached to the vehicle so that it is not subject to displacement when loading or unloading a heavy power mobility aid and that no gap between vehicle and ramp exceeds 5/8 inch.
The 5/8 inch gap specified is based on the width of a wheelchair front caster. In this case, the Board believes simplicity should be the rule. The specified dimension is easy to measure whereas specifying a performance criterion would require the ramp manufacturer to first make an independent determination of what constitutes an appropriate gap for a variety of mobility aids. The measurement does not appear to be burdensome.
With respect to portable ramps, the ADA legislative history specifically mentions portable ramps as a viable option for some vehicles. The principal complaint about portable ramps has usually been the possibility of slipping which the Board believes is adequately addressed by the requirement that the ramp be attached to the vehicle when in use for boarding and alighting. Several commercially available portable ramps have brackets which are attached to the vehicle and which permit quick connect and disconnect. Others have a hole-and-pin arrangement which allows for firm attachment while in use. The definition of "firmly attached" in this case means that the ramp does not move enough to allow a gap between vehicle and ramp greater than 5/8 inch under any conditions, not necessarily that the ramp be rigidly or permanently attached.
A compartment, securement system, or other appropriate method shall be provided to ensure that stowed ramps, including portable ramps stowed in the passenger area, do not impinge on a passenger's wheelchair or mobility aid or pose any hazard to passengers in the event of a sudden stop or maneuver.
This section of the guidelines addresses the provision of a stowage compartment, securement system, or other means of ensuring that the ramp does not pose a hazard. In many situations where portable ramps are currently used, the ramp is simply set inside the passenger compartment, sometimes leaning against the passenger's mobility aid where it could cause injury in a sudden stop or maneuver. Some ramps automatically stow in a pocket under the floor or are folded back over the step. At least one manufacturer provides a storage area immediately inside the door as part of the handrail configuration.
If provided, handrails shall allow persons with disabilities to grasp them from outside the vehicle while starting to board, and to continue to use them throughout the boarding process, and shall have the top between 30 inches and 38 inches above the ramp surface. The handrails shall be capable of withstanding a force of 100 pounds concentrated at any point on the handrail without permanent deformation of the rail or its supporting structure. The handrail shall have a cross-sectional diameter between 1 1/4 inches and 1 1/2 inches or shall provide an equivalent grasping surface, and have eased edges with corner radii of not less than 1/8 inch. Handrails shall not interfere with wheelchair or mobility aid maneuverability when entering or leaving the vehicle.
During the rulemaking process, the Board solicited input on whether ramps should be required to have handrails. Opinion was divided. One suggestion was to require handrails on ramps with a slope greater than 1:12 or longer than 6 feet but other entities were concerned that handrails would interfere with maneuverability of wheelchair and mobility aid users.
The Board generally agrees that "short" ramps and bridge plates do not need handrails. Unfortunately, there is no general agreement on the definition of "short". Since most ramps and bridge plates will probably be "short" in some sense, the Board has not made the provision for handrails on ramps mandatory. However, where they are provided, they must meet structural requirements and not interfere with maneuverability. The Board will further review this issue when the guidelines are revised and updated.
(d) Securement devices
(1) Design load
Securement systems on vehicles with GVWRs of 30,000 pounds or above, and their attachments to such vehicles, shall restrain a force in the forward longitudinal direction of up to 2,000 pounds per securement leg or clamping mechanism and a minimum of 4,000 pounds for each mobility aid. Securement systems on vehicles with GVWRs of up to 30,000 pounds, and their attachments to such vehicles, shall restrain a force in the forward longitudinal direction of up to 2,500 pounds per securement leg or clamping mechanism and a minimum of 5,000 pounds for each mobility aid.
These requirements are taken directly from the Guideline Specifications. The force requirements for different weight vehicles is based on research on the g-forces experienced by various vehicles and their crash profiles. Smaller vehicles generally experience higher g_forces than large buses. In the absence of new data or research, the Board does not believe a change from the previous guidelines is warranted. The significant forces during collision are imposed primarily on the rear securement legs (for a forward-facing securement). Four-point securement systems are common in demand responsive and some fixed route operations but the two forward straps are primarily designed to provide containment and reduce or prevent rebound. Therefore, the front straps are not subjected to the same forces. This section is not intended to suggest a two-point securement system. However, most securement devices consist of two straps or clamping devices, one attached to each side of the wheelchair or mobility aid frame. As such, each leg accounts for about half of the force of restraint. At least one device in current use has a metal bracket which has a hook on each side that attaches to the wheel axles, both of which are secured to the vehicle floor through a single belt. In this case, the single belt must accommodate all of the 4,000 or 5,000 pounds of force, depending on the vehicle size. The more securement straps or devices used for each wheelchair or mobility aid, the less force each one must accommodate individually. To be effective, the securement devices must be attached to the wheelchair or mobility aid frame, not the wheels.
There are several securement devices which have been used successfully in a variety of situations which are described in the Board's technical assistance brochure "Securement of Wheelchairs and Other Mobility Aids on Transit Vehicles." This brochure, available free from the Board, provides detailed technical specifications for securement devices and lists available resources. Such devices, properly installed, should meet these guidelines. In addition, there are several new and on-going projects designed to produce better securement devices.
(2) Location and size
The securement system shall be placed as near to the accessible entrance as practicable and shall have a clear floor area of 30 inches by 48 inches. Such space shall adjoin, and may overlap, an access path. Not more than 6 inches of the required clear floor space may be accommodated for footrests under another seat provided there is a minimum of 9 inches from the floor to the lowest part of the seat overhanging the space. Securement areas may have fold-down seats to accommodate other passengers when a wheelchair or mobility aid is not occupying the area, provided the seats, when folded up, do not obstruct the clear floor space required. (See Fig. 2)
The clear floor area is consistent with the definition of a common wheelchair or mobility aid. Service animals should be able to be accommodated in an area adjacent to the space specified, not necessarily within it. Notice that the area may overlap an adjacent access aisle. However, there is no requirement that the access aisle remain clear and unobstructed by another wheelchair or mobility aid. The Board strongly recommends against interior designs which create "first-on-last-off" situations because such designs impose severe operational constraints on system operators.
Figure 2 shows the amount of the required space which can be accommodated under a seat provided there is a minimum clearance of 9 inches under the seat or object. The requirement, however, is not intended to be construed as pertaining only to seats. That is, a modesty panel or other fixture could also overhang the space, provided the same clearances are adhered to. Since a common wheelchair or mobility aid cannot achieve the required minimum clearance, two wheelchair or mobility aid spaces cannot overlap.
Fold-down seats may be placed in the securement area provided they do not reduce the required area when folded. Quick-release seats could also be placed in the securement area if they can be removed without affecting the provision of service. For example, if the seat on a fixed-route vehicle can be quickly and easily removed by the driver, it could be used. Seats which are bolted down would not generally provide equivalent service even in a demand responsive system if the time needed to remove seats caused a delay in the provision of service which was greater than that allowed for others. On the other hand, if all trips on a demand responsive system required advance notice so that the time needed to remove the seats did not affect response time, bolt-in seats would not be precluded.
(3) Mobility aids accommodated
The securement system shall secure common wheelchairs and mobility aids and shall either be automatic or easily attached by a person familiar with the system and mobility aid and having average dexterity.
The critical part of the above performance requirement is that the system, whatever its design, accommodate common wheelchairs and mobility aids, as defined in �92.3, including power wheelchairs and three-wheel scooters. Thus, a system consisting only of wheel clamps or "rim pins", which can be attached only to chairs of a particular design (i.e., large rear wheels with open spokes), clearly does not meet the requirements. Wheel clamps and rim pins do not accommodate many power wheelchairs, particularly the so-called power base chairs, or three-wheel mobility aids.
While there is no requirement to retrofit existing vehicles, the DOT regulation does not permit a transit operator to deny service to persons with disabilities even if its
current securement device does not fit the particular wheelchair or mobility aid. See 49 CFR 37.165(d). The operator is required to do the best he or she can with the existing system or device. Since securement devices exist which can secure common wheelchairs and mobility devices at moderate cost (one operator in the DOT Advisory Committee meeting reported a cost of $75), operators may wish to consider installing new devices. The brochure Securement of Wheelchairs and Mobility Aids on Transit Vehicles is available from the Board at no cost.
Some entities have suggested that standards for wheelchairs and mobility aids be developed which would require the provision of a common securement point. Neither the ADA nor any other statute confers upon the Board the authority to set standards or guidelines for wheelchairs and mobility aids. However, the development of some standards is currently under way through the International Standards Organization (ISO) and RESNA, a professional society of experts in rehabilitation technology. Furthermore, operators may want to get in touch with the local Independent Living Center to investigate whether there are wheelchair or mobility aid dealers or service and repair shops which have devised, or can devise, attachments or modifications to some types of wheelchair or mobility aid to make them compatible with the particular securement device or system.
In vehicles in excess of 22 feet in length, at least one securement device or system required by paragraph (a) of this section shall secure the wheelchair or mobility aid facing toward the front of the vehicle. In vehicles 22 feet in length or less, the required securement device may secure the wheelchair or mobility aid either facing toward the front of the vehicle or rearward. Additional securement devices or systems shall secure the wheelchair or mobility aid facing forward or rearward. Where the wheelchair or mobility aid is secured facing the rear of the vehicle, a padded barrier shall be provided. The padded barrier shall extend from a height of 38 inches from the vehicle floor to a height of 56 inches from the vehicle floor with a width of 18 inches, laterally centered immediately in back of the seated individual. Such barriers need not be solid provided equivalent protection is afforded.
In the original proposal, the Board pointed out that all available research data indicate that forward or rear-facing securement is the safest configuration and asked whether rear facing securement should be permitted. In light of the strong support for permitting rearward facing systems, the Board has included provisions for them in the final guidelines. Also, there was overwhelming support for permitting only forward or rearward facing securement. Several responses explicitly affirmed the conclusions of the research and none offered any evidence to suggest that the data were incorrect. The only objections arose from a concern for space limitations.
The section requires at least one forward facing system on vehicles in excess of 22 feet, with any additional positions permitted to be either rearward or forward facing. Vehicles 22 feet in length or shorter may provide only rearward facing systems or locations, at the option of the specifier. A requirement has also been added for a padded barrier for rearward facing systems, analogous to the headrests provided on many automobile seats. The padded barrier does not have to be solid. Barriers provided on some vehicles have consisted of a series of padded bars with spaces between, specifically for driver vision. It is also possible that the barrier could be removed or folded when the space is not occupied. It is critical, however, that the barrier be provided for rearward facing systems to prevent severe, possibly fatal, whiplash. Rearward facing systems are optional and operators can provide only forward facing systems.
The wording of this provision above is as it appears in the final guidelines issued by the Board. It contains an editorial revision, to clarify some confusion about the padded barrier, not included in 49 CFR 38.23(d)(4). The DOT provision is intended to be consistent with the Board's final guidelines which requires that the padded barrier pertain only to the securement locations and devices which are rear facing.
Side-facing securement is not permitted under any circumstances. This prohibition is not only based on the results of crash tests but is also related to the dynamics under ordinary sudden stop conditions. That is, during a sudden or panic stop, the wheels of a side-facing manual wheelchair in contact with the vehicle floor experience a force perpendicular to the plane of the wheel. However, the wheels are only intended to support forces radially from the axle. Engineers investigating the dynamics of wheelchairs in accordance with the new ISO standards have reported that wheels subjected to a perpendicular force will typically "dish" and fail under a force of 250 pounds, one tenth the force required to be sustained by the securement system itself. Power-base wheelchairs, some electric wheelchairs with "mag" wheels, and three-wheel mobility aids may fair somewhat better but three-wheel scooters have a higher center of gravity and will tend to tip under sideward forces. Since the DOT rule no longer permits operators to require the users of such devices to transfer to a fixed seat, the securement system must be capable of securing the mobility aid while occupied.
It also appears as if the concern for space is based on a misunderstanding of the requirements of this guideline as well as the dynamics of securement. First, this section does not apply to fixed seats provided for ambulatory passengers, as they are already covered by Federal Motor Vehicle Safety Standards for seat attachment and can face in any direction consistent with those standards. Second, some operators appear to believe that space can be conserved by placing two side-facing wheelchairs or mobility aids immediately adjacent to each other. These suggested configurations seem to assume wall-mounted rim-pins, which do not meet the requirements for securement of all common wheelchairs and mobility aids. In order to provide adequate securement for a side-facing wheelchair or mobility aid, only belts are currently available and they would need to be mounted in such a way that at least two feet would be required between wheelchairs or mobility aids to achieve the appropriate belt angle.
With respect to lap and shoulder belts, all but two responses to the original proposal supported a requirement for them. Again, from the available crash test data, lap and shoulder belts are more important on small vehicles, where the g-forces are greater. A requirement has been included in section 1192.23(d)(7) to require a lap and shoulder belt system at each securement location on vehicles of any length.
When the wheelchair or mobility aid is secured in accordance with manufacturer's instructions, the securement system shall limit the movement of an occupied wheelchair or mobility aid to no more than 2 inches in any direction under normal vehicle operating conditions.
The majority of responses to the original proposal supported this requirement, although a few said it was too stringent while others said it was too liberal. It was pointed out that the requirement for a 2 inch movement could be met only under normal operating conditions, not in a crash, and the final provision limits the application to normal operating conditions. In fact, some elasticity is desirable to absorb shock from collisions or even emergency stops. Note also that the provision applies to systems attached in accordance with the manufacturer's instructions.
When not being used for securement, or when the securement area can be used by standees, the securement system shall not interfere with passenger movement, shall not present any hazardous condition, shall be reasonably protected from vandalism, and shall be readily accessed when needed for use.
This section requires that securement devices not pose a hazard when stowed properly. Some entities contend that the area over the securement device have fold down seats and not be used by standees when not occupied by a wheelchair or mobility aid user. Whether standees are permitted to occupy the area over the securement device when not occupied by a wheelchair or mobility aid user is an operating decision to be made by the operator. The guidelines are intended to provide accessibility in a safe manner.
(7) Seat belt and shoulder harness
For each wheelchair or mobility aid securement device provided, a passenger seat belt and shoulder harness, complying with all applicable provisions of 49 CFR Part 571, shall also be provided for use by wheelchair or mobility aid users. Such seat belts and shoulder harnesses shall not be used in lieu of a device which secures the wheelchair or mobility aid itself.
As discussed above under orientation, there was significant support for the provision of a seat (lap) and shoulder belt at each securement position. Whether a true "harness" or a conventional diagonal shoulder belt is provided, it must meet all applicable provisions of Federal Motor Vehicle Safety Standards (FMVSS) at 49 CFR Part 571. In an automobile, a conventional diagonal shoulder belt is anchored to the frame above the door and connects to the lap belt on the opposite side. However, the same point on a bus, above the side window, may not have the required structural strength. Attaching the belt with screws is not adequate to meet the FMVSS requirements. A true harness, connected to an anchor point on the floor, provides better stability for the passenger (the diagonal belt causes some pivoting of the torso) but may be more difficult to install and use. Because of the g-forces involved, this arrangement may be more suited to vans and small vehicles. Diagonal shoulder belts can work, if installed properly.
The seat and shoulder belt are in addition to the wheelchair or mobility aid securement device. The aid must be secured independent of the passenger belt system. Under no conditions is the passenger seat and shoulder belt to be used to secure both simultaneously. In the event of a crash or sudden stop, the wheelchair or mobility aid would move forward, squeezing the passenger between the chair and the belt, possibly causing serious injury. Also, the lap belt must cross a passenger's pelvic region, not the abdomen or chest. Belts placed around the wheelchair backrest and a passenger's chest or abdomen should never be used.
�92.25 Doors, steps and thresholds
(a) Slip resistance
All aisles, steps, floor areas where people walk and floors in securement locations shall have slip-resistant surfaces.
This is a general performance requirement. As a result of the difficulties of specifying an adequate measure of the static coefficient of friction, no specific value is imposed in the final provision. Advisory guidance on slip resistance has been placed in the appendix, which has been included in this document under the discussion of slip resistance for lift platforms. See section 1192.23(b)(6), above.
All step edges, thresholds, and the boarding edge of ramps or lift platforms shall have a band of color(s) running the full width of the step or edge which contrasts from the step tread and riser, or lift or ramp surface, either light-on-dark or dark-on-light.
A specific value for contrast has not been included due to the practical difficulty of measuring it. The original proposal did contain a formula derived from research on signage sponsored by the Board. The formula has been deleted from the final guidelines for transportation vehicles and placed in the appendix as advisory material.
In general, it is recommended that the contrasting band material contrast by at least 70%. Contrast in percent is determined by:
Contrast = [(B1 - B2)/B1] x 100
where B1 = light reflectance value (LRV) of the lighter area
and B2 = light reflectance value (LRV) of the darker area.
Note that in any application both white and black are never absolute; thus, B1 never equals 100 and B2 is always greater than 0.
(c) Door height
For vehicles in excess of 22 feet in length, the overhead clearance between the top of the door opening and the raised lift platform, or highest point of a ramp, shall be a minimum of 68 inches. For vehicles of 22 feet in length or less, the overhead clearance between the top of the door opening and the raised lift platform, or highest point of a ramp, shall be a minimum of 56 inches.
In the original proposal, the requirements for large buses and vans were contained in separate subparts. Subpart G for small buses and vans contained a provision for minimum door height of 56 inches consistent with the Guideline Specifications issued in 1986. A question in the preamble asked whether a minimum door height should be specified for large buses and what it should be to allow space for overhead door opening mechanisms. Bus manufacturers suggested minimum door heights ranging from 68 inches to 72 inches. No responses were received on the proposed door height requirement for vans and small buses.
Based on the information supplied by the bus manufacturers which chose to respond, the Board selected the height which the information indicated would pose no problem, even though the vertical clearance of 5'8" represents only approximately the 70th percentile person with a disability.
The intent of the requirement is to provide clearance for standees, especially when they must pass through the door while on the raised lift platform. However, one lift design, sometimes called the "elevator" type, involves a standee position fully inside the vehicle. In this configuration, the platform is lowered to the ground and the individual passes though the opening which has a vertical clearance considerably greater than 68 inches. The individual then stands at the full inboard edge of the platform, as the position of the handrails requires, and is raised fully within the vehicle, inside the door. Since the standee never needs to pass through the door opening on the raised lift platform, the FTA Administrator has determined that such a configuration constitutes "equivalent facilitation" with respect to the door height requirement. It should be pointed out that the equivalent facilitation determination applies only to the described configuration. That is, if a different lift is used, one which raises the standee outside the vehicle, the door height requirement would apply. Only when the standee need not pass through the door is equivalent facilitation provided.
Notwithstanding any overhead clearance, it is still possible that an individual could strike his or her head on the door header. A person standing on an elevator-type lift, rising inside the vehicle, might actually be more prone to striking his or her head because the potential obstruction is behind. Operators must take care to warn passengers of such dangers before boarding. It is probably a good idea to provide this information in printed material, as well.
The door height requirement for small buses and vans poses a different problem. The height requirement, which has been in effect since 1986, is based on the seated height of a 95th percentile male in a wheelchair or mobility aid with a seat height of 18 inches. The seats of many power wheelchairs and three-wheel mobility aids are higher and tall people normally need higher seats to allow a seated posture which does not promote pressure sores. Although the required height does not accommodate standees, the Board did not impose the greater height because it may not be feasible for some small vehicles. The 56-inch requirement has been the standard since at least 1986 and imposing a greater height could adversely affect a small industry. Furthermore, the specification applies only to those vehicles required to be accessible by the DOT rule. Since most small vehicles are used in demand responsive service, every vehicle need not be accessible, provided there are enough vehicles to provide equivalent service to persons who need them. See 49 CFR 37.77, 37.101(d) and 37.103(c)-(d).
�92.29 Interior circulation, handrails and stanchions
(a) Interior handrails and stanchions shall permit sufficient turning and maneuvering space for wheelchairs and other mobility aids to reach a securement location from the lift or ramp.
This is a general performance requirement for maneuverability. The characteristics of vehicles, especially when the lift or ramp is located in the front door, do not lend themselves to the common accessibility standard applied to buildings and facilities. The Board recognizes that the provision of a 36 inch aisle is desirable but that is not always possible on all vehicles. Until further investigation on maneuvering space is conducted, the performance requirement should suffice. The need for more specificity will be considered when the guidelines are revised and updated.
(b) Handrails and stanchions shall be provided in the entrance to the vehicle in a configuration which allows persons with disabilities to grasp such assists from outside the vehicle while starting to board, and to continue using such assists throughout the boarding and fare collection process. Handrails shall have a cross-sectional diameter between 1 1/4 inches and 1 1/2 inches or shall provide an equivalent grasping surface, and have eased edges with corner radii of not less than 1/8 inch. Handrails shall be placed to provide a minimum 1 1/2 inches knuckle clearance from the nearest adjacent surface. Where on-board fare collection devices are used on vehicles in excess of 22 feet in length, a horizontal passenger assist shall be located across the front of the vehicle and shall prevent passengers from sustaining injuries on the fare collection device or windshield in the event of a sudden deceleration. Without restricting the vestibule space, the assist shall provide support for a boarding passenger from the front door through the boarding procedure. Passengers shall be able to lean against the assist for security while paying fares.
The 1-1/2 inch clearance is the industry standard and is consistent with the White Book specification. The handrail across the fare box is currently required by 49 CFR Part 609. The wording above has been taken from the White Book.
(c) For vehicles in excess of 22 feet in length, overhead handrail(s) shall be provided which shall be continuous except for a gap at the rear doorway.
This requirement is taken directly from 49 CFR 609.15 for vehicles in excess of 22 feet. Section 1192.29(c) has been revised to be consistent with that regulation. The design of small vehicles is such that overhead handrails may not be needed or practical, due to the generally much lower ceiling.
(d) Handrails and stanchions shall be sufficient to permit safe boarding, on-board circulation, seating and standing assistance, and alighting by persons with disabilities.
This requirement is currently contained in 49 CFR Part 609 and has been in effect for FTA-funded buses since 1976.
(e) For vehicles in excess of 22 feet in length with front-door lifts or ramps, vertical stanchions immediately behind the driver shall either terminate at the lower edge of the aisle-facing seats, if applicable, or be "dog-legged" so that the floor attachment does not impede or interfere with wheelchair footrests. If the driver seat platform must be passed by a wheelchair or mobility aid user entering the vehicle, the platform, to the maximum extent practicable, shall not extend into the aisle or vestibule beyond the wheel housing.
This requirement has been included to address a common problem encountered in buses with front door lifts. Frequently, there is a vertical stanchion immediately behind the driver platform. This stanchion often interferes with wheelchair footrests when the user attempts to turn into the aisle from the lift. A relatively simply solution is to "dog-leg" the stanchion so that its attachment point to the floor is behind or even with the wheel housing. Another solution is to terminate the stanchion at the lower seat rail of the aisle-facing seat immediately behind the driver.
Another problem often encountered with front door lifts is a driver seat platform. The best solution is to eliminate the platform altogether. If this is not practicable, the platform should be angled back, rather than rounded, so that it does not extend into the aisle.
(f) For vehicles in excess of 22 feet in length, the minimum interior height along the path from the lift to the securement location shall be 68 inches. For vehicles of 22 feet in length or less, the minimum interior height from lift to securement location shall be 56 inches.
This section has been added on interior height to be consistent with section 1192.25(c). The height requirement for small vehicles is taken from the FTA-sponsored Guideline Specifications for active wheelchair lifts and is a minimum requirement. The operator may specify a greater height. The height requirement for large vehicles is consistent with the door height requirements in section 1192.25(c).