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Accessibility Guidebook for Outdoor Recreation and Trails

Applying the Forest Service Trails Accessibility Guidelines (Continued)

Constructed Features Associated With Trails

In the FSTAG, the term "associated constructed features" refers to tent pads and platforms, pit toilets, viewing areas, benches, warming huts, and similar structures for trail users. To comply with the Architectural Barriers Act of 1968 and Section 504 of the Rehabilitation Act of 1973 (Section 504), associated constructed features provided along trails—even trails that are not accessible—must be designed to comply with the applicable provisions in the FSORAG.

The path of travel between associated constructed features, as well as the path connecting them to a trail, must comply with the FSTAG. These paths are not ORARs and are not required to meet the technical provisions for an ORAR.

Associated constructed features must be designed appropriately for the setting and in compliance with the applicable provisions in the FSORAG to ensure that the facility can be used for its primary purpose by all hikers, including hikers with disabilities. For example, a trail hut or lean-to with three walls may be provided along a trail. If its floor is above the ground, at least one section of the floor on the open side of the hut must be 17 to 19 inches (430 to 485 millimeters) above the ground to facilitate transfer onto the floor from a wheelchair, as explained in Warming Huts.

Requirements for all recreation facilities, including those that are commonly associated with trails, are contained in the FSORAG and explained in the section titled Applying the Forest Service Outdoor Recreation Accessibility Guidelines. The requirements for tent pads are explained in Camp Unit Tent Pads and Tent Platforms. The requirements for pit toilets are explained in Pit Toilets in General Forest Areas. Constructed features associated with trails must meet the requirements for those features provided in general forest areas (GFAs).

Overview of the FSTAG Implementation Process

Now that you have learned about the extent of application, general exceptions, and the technical provisions, you may be wondering how the whole process ties together. A process overview chart that graphically summarizes the FSTAG steps and sequencing is included below. It guides the trail designer through a series of questions to determine if the FSTAG would apply to the trail being designed. Following this process also enables trail designers to verify that opportunities to provide the highest level of accessibility have been evaluated and that the character, trail class, and experience of the setting have not been changed. You may want to look at a copy of the chart while reading the following explanation of its use.

Step 1: Determine the applicability of the FSTAG

Once a decision has been made to design or alter a trail, three questions must be asked:

  1. Is the designed use "hiker/pedestrian"?
    • If yes,

  2. Does the work meet the definitions for new construction or alteration that are explained in Understanding Trail Terminology?
    • If yes,

  3. Does the proposed trail connect to a trailhead or accessible trail? "Trailhead" is defined in Understanding Trail Terminology.

If the answer to any of those questions is "no," the FSTAG does not apply and no further analysis is required. The finding and reasons that the FSTAG does not apply should be briefly documented and put in the project file. Even so, it is always desirable to incorporate accessibility where opportunities exist.

If the answer to all three questions is "yes," the designer moves to step 2.

Step 2: Identify the Presence of Limiting Factors

This step addresses General Exception 1 and the four limiting factors that are explained in Using the General Exceptions in the FSTAG. The sequence for identifying the limiting factors may vary and does not need to be done in the order illustrated in the process overview chart.

Let's work our way through the process overview chart by asking four questions, each related to one of the limiting factors. The first question will be explained in detail to serve as an example for the other three.

"Does the combined trail grade and cross slope exceed 20 percent for a continuous distance of 40 feet (12 meters) or more?"

If not, the FSTAG may still apply, so you should consider the next limiting factor. A "continuous distance" means a sustained grade without rest areas or more moderate grades or grade breaks. If the alignment can be relocated to get a more moderate grade, this limiting factor doesn't apply.

Illustration of two people using a hand level, survey rod, and survey tape to determine the grade of a section of trail. One man holds the survey rod at the lower end of the trail segment. The other man looks through the hand level at the survey rod from the upper end of the trail segment. The survey tape is stretched between the two men. Text indicates that A equals the horizontal distance of the trail segment measured with the survey tape, B equals the known height between the ground and the hand level, and C equals the height above the ground that is observed on the survey rod by the person looking through the hand level. C minus B equals the vertical distance D between the lower end of the trail segment and upper end of the trail segment, D divided by A equals the slope per foot (or meter) E of the trail segment. The slope percent equals 100 times E. A divided by D equals F. The slope ratio equals 1 to F.
Figure 123—Surveying trail grade with a hand level.

Illustration of two people using a survey tape and digital level to determine the grade of a section of trail. One person is at each end of the trail segment. The survey tape is stretched on the trail between them. The digital level is on the trail with its long dimension parallel to the direction of travel. Text explains that the survey tape measures the running distance, and the digital level displays the slope.
Figure 124—Surveying trail grade with a digital level.

If the grade and cross slope are exceeded, you would need to determine whether a condition for departure exists that permits a deviation from the required grade. If there is no condition for departure, the FSTAG may still apply, so you should proceed to the next limiting factor.

If a condition for departure does exist, document the length of trail that exceeds those grades, the location of the area, and your data source (field survey, clinometer, etc.). The FSTAG requirements don't apply beyond the section with excessive grade.

Next, determine whether the extreme grade and cross slope are more than 500 feet (152 meters) from either end of the trail. If so, FSTAG requirements apply between the end of the trail and this limiting factor. If not, determine whether there is a prominent feature between the end of the trail and this limiting factor. If there is a prominent feature, FSTAG requirements apply from the end of the trail to the prominent feature. If there is no prominent feature, the FSTAG does not apply to this trail at all and no further review or analysis is required. This determination and the applicable condition for departure should be documented for the project file.

Work your way through the other three limiting factors the same way.

"Is the surface unfirm or unstable for 45 feet (14 meters) or more?"

Photo of a person adjusting the pressure on the wheel of a rotational penetrometer. The rotational penetrometer is a wheelchair caster that is mounted within a frame. The frame holds the caster in position against the ground while it is swiveled by hand using an attached rod. This action simulates wheelchair traffic on a surface.
Figure 125—Using the rotational penetrometer to
determine whether a surface is firm and stable.

"Is the trail width 18 inches (455 millimeters) or less for a distance of at least 20 feet (6 meters)?"

"Is there a trail obstacle at least 30 inches (760 millimeters) high?"

If you find a limiting factor where a condition for departure applies, there's no reason to evaluate the trail beyond that point for successive limiting factors. Just look at the section of trail between the limiting factor or prominent feature and the trail terminus. If there are no limiting factors that would prevent compliance with the FSTAG, proceed to step 3.

Step 3: Apply the Technical Provisions

This step involves looking at FSTAG sections 7.3.1 through 7.3.8, which are the provisions for trail grade, cross slope, resting interval, surface, clear tread width, passing space, tread obstacles, protruding objects, and openings. The provisions for edge protection and signs aren't included because they don't affect the accessibility of the trail to the extent the other provisions do.

This summary and the process overview chart don't contain everything you need to know about trail requirements. Designers must refer to the FSTAG for detailed instructions, definitions, conditions for departure, technical provisions 7.0 through 7.3.10, and exceptions.

A series of questions with yes or no answers is asked for each of the provisions listed above, similar to step 2. Let's take trail grade as an example.

First, look at the existing conditions on the ground and determine whether the trail alignment complies with the required grades (1:20 for any distance, 1:12 for up to 200 feet [61 meters], 1:10 for up to 30 feet [9 meters], and so forth). If not, is there a condition for departure that would prevent adjusting the trail alignment or making other changes to achieve compliance? If a condition for departure exists, measure and record the length of the deviation and proceed to the next provision. If the trail alignment complies with the required grades or there is no condition for departure, compliance with the provision for trail grade is required.

Each technical provision is addressed in a similar manner. A determination is made for every provision: either compliance is required, or deviations are permitted. Be sure to measure and record the length of each deviation from a particular provision. Once you have worked through the provisions, proceed to the last step.

If at any point during step 3 you find that the recorded length of deviations from the provisions adds up to 15 percent or more of the total trail length, proceed directly to step 4.

Step 4: Calculate Cumulative Deviation Percentage

This is the final step in determining how much of the trail must comply with the FSTAG as addressed by general exception 2.

Tally up the measurements of permitted deviations from step 3. If they occur on less than 15 percent of the total trail length, the FSTAG technical provisions apply to the entire trail.

However, if the length of permitted deviations is 15 percent or more of the total trail length, the FSTAG applies to only part of the trail, or may not apply at all.

If the first deviation occurs more than 500 feet (152 meters) from one end of the trail, apply the FSTAG from that end of the trail to the first deviation.

If the first deviation occurs less than 500 feet (152 meters) from one end of the trail and a prominent feature is between the end of the trail and the deviation, the FSTAG applies from that end of the trail to the prominent feature.

If the first deviation occurs less than 500 feet (152 meters) from one end of the trail and no prominent feature is between the end of the trail and the deviation, the FSTAG doesn't apply to the trail.

Schematic illustration of a trail from a trailhead to Herman's Peak. Text repeats information described in the Design Tip above.
Figure 126—This trail schematic illustrates how to determine
where the trail must comply with the FSTAG.

That's all there is to it!

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