There are two categories of radon in air tests-

Short Term Tests and Long Term Tests.

Short term tests measure radon levels for exposure periods of 2 days to 90 days, depending on the device. Short term testing is extremely useful when you need results quickly such as during a real estate transaction. Most common tests for radon last 2-7 days.

RTCA® offers the following short-term tests:

Long term tests
measure radon levels for 90 days to one year. These tests give results which are more likely to reflect the seasonal or year round average radon level of the home.

RTCA® offers the following long-term tests: