Step 2: Defining a study area type

Once you create a study area, you need to select the appropriate study area type. Each study area can be defined by rings (radii), donuts (bands), or drive-time polygons.

The measurement units (e.g., kilometers or miles) are pulled from your preference settings. See Setting the default country settings.

In this topic, you will learn how to define a study area using each of the following methods:

• Define a study area by rings
• Define a study area by donuts
• Define a study area by drive-time polygons

Note:

The Drivetime option is only available when the country is set to USA. You will not see the Drivetime option for other countries.

Defining a study area by rings

Rings are calculated as circles, using your site as the center point.

For example, a site with 1, 3, and 5 mile rings will calculate statistics using the following three areas:

• 0-1 mile area
• 0-3 mile area
• 0-5 mile area

The maximum parameter for rings is 300; the minimum parameter is 0.1. Rings automatically default to 1, 3, and 5 miles. You can modify the default parameters in your user preferences. See Setting the default study area type.

Steps:

1. Create a new study area.
2. Select the Rings radio option.
3. Enter three ring radii.
   Note:

   The radii input values can range from 0.1-300 regardless of the metric or US Customary units.

4. Click Apply.

   The study area buffer is drawn on the map.

5. Click Next.

   The Create a Study Area wizard proceeds to the next step. See Step 3: Naming a study area.

Defining a study area by donuts

Donuts are study areas that are cut out like donuts with no overlap. Donut rings offer the traditional ring study without duplication of overlapping areas.

For example, a site with 1, 3, and 5 mile donuts will calculate statistics using the following three areas:

• 0-1 mile area
• 1-3 mile area
• 3-5 mile area

The maximum parameter for rings is 300; the minimum parameter is 0.1. Rings automatically default to 1, 3, and 5 miles. You can modify the default parameters in your user preferences. See Setting the default study area type.

Steps:

1. Create a new study area.
2. Select the Donuts radio option.
3. Enter three donut radii.
   Note:

   The donut parameters can range from .01-300 regardless of the metric or US Customary units.

4. Click Apply.

   The study area buffer is drawn on the map.

5. Click Next.

   The Create a Study Area wizard proceeds to step 3. See Step 3: Naming a study area.

Defining a study area by drive-time polygons

Drive-times are defined by the time it takes to drive from the outder border of the area to a site location. The drive-time polygons are an effective tool for defining areas where access to a site is affected by natural and man-made barriers, such as mountains, rivers, lakes, canyons, bridges, and highways. The drive-time polygons are calculated under normal traffic conditions.

For example, a drive-time with 5, 10, and 15 minute intervals calculates the drive-time report using the following three areas:

• 0-5 minute area
• 0-10 minute area
• 0-15 minute area

The maximum parameter for drive-time polygons is 120 minutes; the minimum parameter is 2 minutes. Drive-times automatically default to 5, 10, and 15 minute intervals. You can modify the default parameters in your user preferences. See Setting the default study area type.

Note:

The Drivetime option is only available when the country is set to USA. You will not see the Drivetime option for other countries.

Steps:

1. Create a new study area.
2. Select the Drivetime radio option.
3. Enter three drive-time durations.
   Note:

   The drivetime duration can range from 1-120 minutes.

4. Click Apply.

   The study area buffer is drawn on the map.

5. Click Next.

   The Create a Study Area wizard proceeds to step 2. See Step 3: Naming a study area.