Final answer:
According to EPA protocols, the minimum distance a radon measurement device should be placed from an exterior opening such as a door or window is 10 feet.
Step-by-step explanation:
The minimum distance a radon measurement device should be placed from an exterior opening such as a door or window, according to EPA protocols, is 10 feet. This is to ensure accurate readings of radon levels, as placing the device too close to an exterior opening may lead to interference from outside air. It is important to follow proper protocols when measuring radon levels to ensure accurate results and to take appropriate action if elevated levels are detected.