Closed-House Violation During a Real Estate Deadline
On Tuesday at 09:00 a measurement professional deploys two 48-hour continuous radon monitors in a 2,400 ft2 two-story house with a finished basement: one in the basement bedroom and one in the first-floor living room. The house has been closed for 14 hours when the test starts. At 14:00 on Wednesday the seller opens six windows and runs a whole-house fan for three hours to clear paint odors. Both monitors log a 4 F temperature drop and a relative-humidity drop from 56% to 37% during that window. The test is scheduled to end Thursday at 09:00. The real estate agent says closing is in three days and asks for the first-floor result only, because it reads 2.9 pCi/L while the basement monitor reads 6.8 pCi/L. The buyer's lender requires a report by Friday. The professional must decide whether the data are reportable and how to handle the deadline.
1. Are the 48-hour results valid? Identify the condition that was violated, explain how the monitor data support your conclusion, and state whether the test can be salvaged.
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The results are not valid. A short-term test requires closed-house conditions for at least 12 hours before the test and throughout it. Opening six windows and running a whole-house fan during the measurement violates that requirement. The monitors independently corroborate the disturbance: a 4 F temperature drop and a 19-point relative-humidity drop at the same time are consistent with a large air exchange, not normal occupancy. You cannot salvage the test by discarding only the disturbed hours, because the dilution affected the whole house and the 12-hour precondition for the remainder was broken. You also cannot assume the basement was unaffected. The defensible options are to notify the client in writing that the test is invalid, restore closed-house conditions, and start a new 48-hour test. If the lender deadline cannot be met, provide a status letter rather than an invalid number.
2. How should you respond to the agent's request to report only the 2.9 pCi/L first-floor result?
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Decline. The lowest livable level in this house is the finished basement because it contains a bedroom. The 6.8 pCi/L basement result, if valid, is the actionable result; the first-floor 2.9 pCi/L does not clear the basement. Reporting only the lower number would misrepresent the house and could affect the buyer's decision. There is an additional problem: the 2.9 pCi/L was collected during a period when closed-house conditions were violated, so it is not a valid result either. Explain in writing to the agent and buyer that the test is invalid and that the basement must be retested under proper conditions. If the agent continues to pressure you to select a favorable number, document the request and reiterate that you cannot report partial or invalid data. Protecting the buyer from an inaccurate clearance is the professional obligation here.
3. What documentation and next steps should you provide before Friday?
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Provide a clear record: device identifiers and calibration dates, start and end times, the closed-house confirmation at deployment, the CRM graphs showing the temperature and humidity excursion, and a written disturbance log noting the date, time, duration, windows, and fan operation. State plainly that the test is invalid and why. Do not backdate or alter the original data. Offer a new 48-hour test beginning after closed-house conditions are restored. If the closing cannot wait, give the lender a letter explaining that a valid result is pending, not a clearance. Keep the original records and all communications with the agent. This documentation protects the client and shows that you followed the protocol rather than yielding to the deadline.