Courtesy of Field Trip Chairmen's Association. Source of this scale is GPAA Sacramento Chapter
1 - 2 Vehicle access and parking to include bus’s, RV’s, handicap vehicles, handicap parking available.
3 - 4 Vehicle access and parking good for most vehicles and RV‘s, no specific handicap parking
5 2 wheel, vehicle parking on rough terrain or trail end
6 2 wheel access or parking on roads, dirt or gravel, limited parking areas, car pooling may be recommended
7 Difficult access by 2 wheel drive, high clearance required (2 wheel SUV‘s, truck’s)
8 4 x 4 or high clearance with Positraction or all wheel slip prevention equipped vehicles.
9 4 x 4 required due to unknown and possibly difficult roads and trails. Possible inclement weather causing changing road conditions on approach or return
10 4 x 4 required, high clearance necessary, experienced 4 x 4 driver. Recovery equipment required, basic survival supplies aboard each vehicle
1 - 2 Flat ground or paved handicap access to and at site
3 - 4 Flat ground, unpaved sections, handicap access with some help
5 ¼ to ½ mile trail to site with moderate difficulty
6 ¼ to ½ mile with trails on hill sides, or through brush and creek beds
7 ½ mile or more to site, difficult trails and ravines or water crossings. Potential exploration for additional sites
8 Difficult trails, difficult access to sites, or difficult collecting conditions at the site. Unknown trail or collecting conditions at other unknown sites in the area. Exploration trips for additional
sites in rough terrain
9 Experienced and equipped expedition participants only
10 Experienced, and equipped, and physically fit participants only