How To Select...

What Are Selection Criteria ?

Before producing an AirData report or map, you need to specify what data should be selected and presented. For example, to produce a report of air monitoring data, you would select a pollutant and year. Options such as pollutant and year are report/map selection criteria.

Nearly all AirData reports and maps have pollutant and year as selection criteria. Some reports and maps have additional criteria, such as:

• Emissions threshold
• Source type
• Monitoring station type
• Page size (lines per page)
• Optional report columns

The selection criteria Web page for each AirData report or map lists the particular criteria available for it. The Web page also indicates which criteria you must specify, and which ones are optional.

How Do I Specify Report/Map Criteria ?

AirData Web pages display report/map selection criteria using lists, checkboxes, and radio buttons. These standard Web page elements allow you to learn what options are available, and to choose among them. On some AirData Web pages, you enter a value (an emissions threshold, for example) as part of the selection criteria.

Lists

With the "Single" list style, you select one of the available choices. The selected choice is visible. Clicking your mouse pointer on the small arrow (triangle) expands the list and makes additional choices visible. Clicking on a choice selects it, collapses the list, and displays the selected choice. (Keyboard alternative: use up and down arrow keys to scroll the list until the desired choice is displayed.)

The "Multiple" list style lets you select any number of the available choices: none, some, or all of them. (In practice, "all of them" may be too many. AirData Web pages indicate how many selections are allowed.) A scroll bar beside the choices allows you to scroll the list, if all choices are not visible. Clicking your mouse pointer on a choice selects it and unselects all other choices. (Keyboard alternative: use up and down arrow keys to scroll to a choice.) The selected choice is highlighted, usually with a different background color.
- To select an additional choice, or to deselect a choice, hold down the Control key (Windows) or Command key (Macintosh) while clicking on a choice.
- To select a contiguous group of choices, click on the first choice, hold down the Shift key, and click on the last choice. (Keyboard alternative: hold down the shift key while scrolling to select a contiguous group of choices.)

Checkboxes

Generally, AirData Web pages use checkboxes in the same way as multiple-style lists (above). The checkboxes let you select all, some, or none of a related group of options.

Radio Buttons

A visual radio button indicator (circle) contains a dot or is filled with a dark shade to indicate the selected state, and is empty in the unselected state. The radio button examples near this paragraph illustrate both states. Click your mouse pointer on a radio button to select the associated choice. (Keyboard alternative: Tab to a radio button and press Space bar, or Tab to a radio button group, and use up or down arrows keys to select among buttons in the group.)