Short-term testing is not useless. Although, in any situation, a greater level of data is always better. I generally tell my clients, " Listen, if you're going to focus on the 7.8 in that one hour, you also need to focus on the 0.9 in the other hour, since we are averaging the data" Everyone wants to focus on the worst case scenario. There is no such thing as too much data or detail in your reports, as long as it is clearly presented in you can explain it standing on your head. It is up to us to help people understand what they are reading and how to interpret it. I do not come from a perspective that less is more in a home inspection. People generally want the detail. A high percentage of people do not even know what radon is and it is probably one of the areas in a home inspection where people are least educated, including our agents. So, learn your reporting system, how to interpret it. Learn when anomalies occur, why they may have happened and how to explain them.... Meaning if you haven't taken a radon course yet, you really should consider it so that you can explain the information to the best of your ability and to best practice. A short-term test does give you a snapshot. I have certainly seen data drastically change over three and four days to the levels that if we went with the first 48 hours, the home would need a mitigation system. But a mitigation system is never a bad thing, as now many contractors are installing fan systems to handle the moisture coming into the home from under the pad anyway as an energy update. So either way, it will be good for the home if a system has to go in.