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 MTDC > MTDC Pubs >1223-2806P-MTDC; Accessibility Guidebook for Outdoor Recreation and Trails T&D Publications Header

Accessibility Guidebook for Outdoor Recreation and Trails

Applying the Forest Service Trails Accessibility Guidelines

General Exceptions in FSTAG

Some public lands are reasonably well suited for pedestrian travel. Other public lands are rocky, soggy, excessively steep, or otherwise less well suited to casual foot traffic. Two general exceptions are provided in FSTAG, section 7.2 to ensure that accessibility is provided to the extent appropriate to the setting where it will have the most benefit, be practicable, and provide a meaningful hiking opportunity.

Document the basis for the determination that either of the general exceptions applies to a trail or a portion of a trail and maintain the documentation with the records of the construction or alteration project. In addition, if General Exception 2 applies, send notification to the U.S. Access Board. Documentation and notification requirements are explained in "Documenting Exceptions and Notifying the U.S. Access Board about Exemptions" of this guidebook.

General Exception 1 allows deviations from the technical requirements if a condition for an exception prohibits full compliance. It's not a complete exemption from the provision, because it requires that the technical requirement must still be met to the extent practicable.

For instance, if Condition for an Exception 3 prohibits importing several tons of stabilization material to ensure that the surface of a trail in a nonmotorized area will be firm and stable during the primary season(s) of use under normally occurring weather conditions, you must still make sure the surface is as firm and stable as is practicable. For instance, if relocating a section of trail a few feet laterally will achieve firmness and stability with native soils during the dry portion of the season or even during part of the wetter season, you must relocate that section. Such measures are practicable and should be utilized. General Exception 1 only applies to the portion of the trail where the condition for an exception exists. On all other sections of the trail, ensure that technical requirements are met. All of the unaffected technical requirements must be met for the full length of the trail, including the section where the condition for an exception prohibits full compliance with the particular technical requirement. Practicable means reasonable rather than technically possible. (See TERMINOLOGY TIP—What's practicable?, page 32.)

Another example of the use of General Exception 1 is when construction of a trail appears to fall under Condition for an Exception 4, where compliance is not possible because the cultural, historic, or significant natural features are protected or are eligible for protection under Federal, State, or local law. For instance, consider a situation where a trail is needed between a stream with endangered aquatic species and a cliff with petroglyphs on it and you can't get the required trail width without either filling part of the stream or destroying some petroglyphs. A narrower trail would be allowed past the petroglyphs. However, the other technical requirements still apply to that stretch of trail and the technical requirement for width still applies to all the rest of the trail.

Design Tip

Compliance is required on both sides of a deviation from the technical requirements.

Although accessible design is based on wheelchair dimensions, clear space, maneuvering room, and reach ranges, only 4 percent of people with disabilities use wheelchairs. The majority of people who have mobility limitations don't use a wheelchair. They either use no assistive devices or rely on crutches, canes, walkers, or braces. They may be able to get around or over an obstacle without too much difficulty. Although steep terrain may be difficult, it may be manageable for limited distances.

Likewise, a person using a wheelchair might need assistance to make it up a steep grade (figure 124) or to get over an obstacle, but after that challenge, the individual can continue on the trail independently if the rest of the trail complies with the accessibility guidelines.

Photo of 4 people on a very rocky trail.  Two people are assisting by a hiker in a wheelchair up a cliff-like section of the trail by pushing from behind. Pulling poles are hooked to the front of the wheelchair so that other people who are not in the photo can also assist by pulling from the front of the wheelchair.
Figure 124—Members of the Northeast Passage
hiking team assist their teammate up a steep
part of the Galehead Trail. She only needs
assistance for a short distance. Photo
credit: Northeast Passage, Durham, NH

General Exception 2 addresses extreme environmental barriers that are effectively impassable and trails with numerous environmental barriers that can't be eliminated. These barriers can make the rest of the trail unreachable for many people with mobility limitations. General Exception 2 may be considered only after applying General Exception 1 so that the trail sections where full compliance with the technical requirements can't be achieved are identified. Then evaluate the entire trail comparing the trail sections that can and can't meet the full technical requirements to determine whether it would be impracticable for the entire trail to comply with the accessibility requirements.

The following condition criteria have been accepted by the U.S. Access Board for identifying when extreme environmental barriers may exempt an entire trail from technical accessibility requirements:

  • A combination of running slope and cross slope exceeds 1:2.5 (40 percent) for more than 20 feet (6 meters) (figure 125).

  • An obstacle 30 inches (760 millimeters) high or more crosses the full tread width of the trail (figure 126).

  • The surface of the trail is neither firm nor stable for a distance of 45 feet (14 meters) or more.

  • The tread width of the trail is 12 inches (305 millimeters) or less for a distance of 20 feet (6 meters) or more.

  • 15 percent or more of the trail does not fully comply with the technical requirements.

Photo of two people going up and two people coming down a stair step-like trail on the side of a cliff.  Metal railings are provided on the drop-off side of the trail.
Figure 125—The combination of running slope
and cross slope on the trail to Hanging Lake is
so severe for such an extended distance that
the entire trail was exempted from the
technical requirements.

Illustration of a hiker wearing a backpack approaching a section of trail where natural rock outcroppings create 13-inch (330 millimeter) and 33-inch (840 millimeter) vertical barriers in the route. Text indicates the height of the two barriers.
Figure 126—The 33-inch (840-millimeter) rock face is an
example of an extreme environmental barrier.

Some long-distance trails, such as the Continental Divide, Pacific Crest, Appalachian, and Florida National Scenic Trails and the Nee-Me-Poo National Historic Trail, span many districts or forests. For these trails, only the length of trail planned for construction or alteration within the current planning period is considered when figuring the 15 percent, not the entire length of the trail. This principle applies even if the planning period is several years long. Consider connected sections of trail that will be constructed or altered over several years, together. Do not consider unconnected segments of trail that are covered by the same planning process together, unless there is a special circumstance where several segments function together to access one attraction or serve one purpose.

Short Hikes and Interesting Features

Sometimes it makes sense to provide a short section of trail meeting the technical requirements for accessibility on a trail that would otherwise be totally exempted from the technical requirements under General Exception 2. Even if visitors can't hike the entire trail, a short hike may be enjoyable (figure 127). If there are no uncorrectable environmental barriers and few or no significant conditions requiring exceptions between the trailhead and the first extreme environmental barrier, and that trail segment is at least 500 feet (152 meters) long, consider constructing that section of trail to meet the technical requirements even though the rest of the trail is not accessible.

Photo of a mother and her two children watching waterfowl from an overlook at a lake.  The mother is using a motorized scooter.
Figure 127—A short hike on a trail that meets accessibility standards
brings the family to a viewing platform next to Picture Lake at the Mt.
Baker-Snoqualmie National Forest.

A short section of trail is especially enjoyable if an interesting natural, cultural, or historic feature is located between the trailhead and the first extreme environmental barrier. The feature might be the focal point, main attraction, or destination of the trail or it may simply be an interesting secondary feature, such as a boulder outcrop, a waterfall, a grouping of old or unique trees, a cultural or historic structure, a wildflower meadow, an area popular for wildlife viewing, or a vista. In such cases, hikers would appreciate you constructing the section of the trail leading to the prominent feature in compliance with the technical accessibility requirements.

Here's an example of how the guidance on General Exception 2 can be used. Consider the design for a new 1-mile (1,600-meter) -long trail with a waterfall (an interesting feature) about 300 feet (91 meters) from the trailhead. Fifteen percent of 1 mile (1,600 meters) is 792 feet (240 meters). Add together all the lengths of trail where technical requirements can't be met because of conditions for an exception. If the total length is more than 792 feet (240 meters), the trail would be eligible for a total exemption from the technical requirements of FSTAG. However, if there are no uncorrectable environmental barriers and few or no significant conditions requiring exceptions between the trailhead and the waterfall, that section of trail should, in most cases, comply with the technical requirements even though the rest of the trail does not.

Documenting Exceptions and Notifying the U.S. Access Board About Exemptions

U.S. Access Board About Exemptions When a condition for an exception prohibits full compliance with a specific technical requirement on a section of trail as allowed in General Exception 1, document the reason that full compliance wasn't achieved and file it with the project records for the trail construction or alteration project. Include which condition for an exception applies to the trail or segment of trail, the reason that it applies, the date the decision that the exception applies was made, and the names of the individuals who made the decision.

Infrequently, extreme or numerous conditions for exemptions make it impracticable to provide a route that meets the requirements, so General Exception 2 allows exempting the entire trail from the technical requirements. In these cases, document the explanation of the conditions that make it impracticable for the entire trail to comply. Retain the documentation with the records for that construction or alteration project. Notify the U.S. Access Board of the determination to exempt the entire trail. Contact information for the U.S. Access Board is available at The U.S. Access Board has drafted a form that may be used to document and submit an exemption decision. The form will be available at when the U.S. Access Board final guidelines are published.