2016 ADA CHECKLIST FOR POLLING PLACES

Sloped Surfaces

Measuring the slope of a ramp, parking space, pedestrian route, or other ground or floor surface is important to identify whether the surface is accessible. Two slope measurements perpendicular to one another should be taken at each location. One is the running slope that runs parallel to the direction of travel and the other is the cross slope, which runs perpendicular to the running slope.

The amount of slope or grade is described as the proportion of a vertical rise to a horizontal length. It is usually described as:

• a ratio (e.g., 1:20, means one unit of vertical rise for each 20 units of horizontal length); or
• a percentage (e.g., 8.33% which equates to a ratio of 1:12 or 4.76 degrees).

The easiest way to measure slope is to use a digital level. The digital display gives a reading that may be shown as a ratio, percent, or degree. Calibrate the digital level before each use.

A digital level that can be used with measurements in degrees, percentages, or ratios

Another way to measure slope is to use a 24 inch level with leveling bubbles and a tape measure. Place the level on the sloped surface in the direction you wish to measure. Rest one end of the level at the highest point of the sloped surface and lift the other end (see image) until the bubble is in the middle of the tube. This is the "level" position. While the level is in this position, measure the distance between the bottom end of the level and the sloped surface below. If the distance is two inches or less, then the slope is 1:12 or less. When the distance is more than two inches, record the distance on the checklist so the exact slope can be calculated later. For measuring cross slope, if the distance measured from the level position is 1/2 inch or less then the slope is 1:48 or less.

Measuring slope using a 24 inch bubble level and tape measure