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Short-Term Test

 

 

A PGL report for a short-term radon and radon decay products test utilizing an ERPISU has 3 test specific areas as follows:

Test Results (Located near the top of page 1 of your report)

Test and Building Details (Located in the lower portion of page 1 of your report)

Measurement Precision (Located on the upper portion of page 2 of your report)

Test Results:

Property Tested: Address of the property within which the test was conducted

Average Radon Decay Product Activity: The number presented is in units of Working Levels (WL) and is a direct measurement of the radon decay products that cause the health risk associated with radon.  This number is to be compared to the US EPA guidance of 0.02WL as shown in the July 2000, Home Buyer's and Seller's Guide.

Average Equivalent Radon Levels Based on this Test:  This is an estimation of the amount of radon gas needed to be in a room to result in a level of radon decay products as measured by this test.   This allows the radon decay product measurement to be expressed in terms of pCi/L, which may be a more familiar measurement, and can be compared to the EPA guidance of 4.0 pCi/L.  The calculation used to determine this equivalency is from section 4.7 of the US EPA "Protocols for Radon Decay Product Measurements in Homes," EPA 402-R-92-003.

EPA Recommendations Based on Results of this Test: The recommendations within this section are based upon the Average Radon Decay Product Activity or Average Equivalent Radon Level with conditional responses as follows:

Radon Decay Product Activity Average Equivalent Radon Response
Less than 0.02 WL Less than 4.0 pCi/L Although some risks exists at exposures of less than 0.02 WL, based upon these results, and the assumption that proper testing procedures were followed, the US EPA does not recommend follow-up action.  Should building conditions change significantly, retesting in the future may be advisable.
Equal to or greater than 0.02 WL Equal to or greater than 4.0 pCi/L Assuming proper testing procedures were followed, the US EPA recommends follow-up action either in the form of mitigation (reducing exposure) or if time allows and levels are less than 0.05 WL, determine long-term exposure by conducting a long-term (>90 day) measurement.

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Test and Building Details

In this section of the report, the measurement professional will note certain attributes of the building and also specific conditions that could have affected measurement, as well as other relevant details. 

Test Start Date and Time: The date and time is expressed as a single string, with the first set of digits referring to the month, the second set of digits being the day within that month, the third set of digits being the year within the century beginning with 2000, and the last four numbers referring to the hour and minute (based on a 24-hour clock).  All dates and times to be local time for the time zone in which the building is located.

Location of test:  This is a description of the room in which the test was conducted.

Closed House Conditions: A properly conducted short-term test requires that all exterior doors and windows be closed (except for normal entry and exit) for 12-hours prior to and all during a minimum 48-hour test.  The professional will indicate either a Yes or No, to the best of their knowledge.  This area should be marked Yes.  If this field is marked No, the test would be considered invalid.  In this case, please contact your measurement professional.

House Occupied: A Yes or No answer will be indicated here and is a further indication of the potential for test tampering.  Neither a Yes or No reply is reason for concern.

Furniture in Home: This is filled in as either a Yes or No response and is only indicated for research purposes to determine the impact that additional surfaces, as presented by furniture may have on the beneficial reduction of radon decay products.

Test Type: This will be filled in as either Pre-Mitigation meaning there is no radon or radon decay product reduction system in the home, or as Post-Mitigation to determine the effectiveness of a Mitigation system. 

Individual Detectors: The ERPISU has two parallel measurement heads to allow for duplicate measurements.  The Radon Decay Product Activity reported in the Test Results section are actually the average of these two measurements.  The presence of duplicate measurements provides the analyst the means to check the precision of these measurements.  It is expected that there will be some difference in the measurements, for a determination if these are too far apart, see the Measurement Precision portion of your report on the second page and described below.  The individual results are expressed in units of Working Levels (WL).

Test Stop Date and Time: The date and time is expressed as a single string, with the first set of digits referring to the month, the second set of digits being the day within that month, the third set of digits being the year within the century beginning with 2000, and the last four numbers referring to the hour and minute (based on a 24-hour clock).  All dates and times to be local time for the time zone in which the building is located.

Forced Air System: This indicates if a forced air heating or cooling system exists in the house and what mode the fan unit is in.  If there is no forced air system this portion will either be blank or say None.  If there is a forced air system, the mode will either be Auto or Constant On.  It should be noted that air circulation can have a beneficial effect in reducing radon decay products.  If this test was conducted with the fan in Auto Mode, operating the fan in Constant Mode could reduce radon and radon decay products further than indicated by the results of this test.  Conversely, if the test was conducted with the fan in constant, operating it on Auto (intermittent) could increase radon and radon decay products to a level higher than indicated by this test.

Air filter System: More and more people are installing air filtration systems to reduce airborne particulates.  These can have a beneficial effect in reducing radon decay product exposures.  This field will indicate if there is a filter in the home and the type.  NOTE:  If a test was conducted with an air filter in the home in the home and later the filter is turned off or removed, radon decay product levels could increase above the values reported in your report.  If this is a whole house filter, removal is unlikely, but it should be maintained and operated in the manner it was operated during the test if results similar to those observed during the test are desired.

Sq Ft of Building:  An approximate measurement of the size of the home.  This is for research purposes and has no impact on the results of this report.

Mitigation System: This field is for the description of a radon or radon decay product mitigation system if such a system exists within the building.  It is important to note that if a radon or radon decay product reduction system is operating in the building, the results of this report are impacted by this system.

Actual Radon Measured:  The ERPISU system measures radon in addition to radon decay products.  This measurement provides an indication of what the potential risk is in the building if factors that may be reducing radon decay exposure (such as air circulation, or air filters) change, and even more so, if indoor particulate levels increase significantly (i.e. if someone smokes frequently within the building).  

Equilibrium Factor:  This is the percentage of radon decay products suspended in the air as compared to the theoretical amount of radon decay products produced by the radon present.  The US EPA assumes that most homes have equilibrium levels of 40-50%.  However, this level can be much lower (which is good) in homes with air circulation and low particulate levels.

Notes:  These will be unique circumstances or recommendations made by the measurement professional who conducted the measurements.

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Measurement Precision

This section describes a calculation performed on the duplicate radon decay product measurements.  This is a unique feature of the ERPISU system that provides an indication of the precision of the overall measurement. 

Relative Percent Difference:  This is the difference of the two radon decay product measurements divided by their average and expressed as a percentage.  Beneath this value is a conditional statement that provides an indication of confidence.  The response will be as follows:

Duplicate Results Desired Range or Relative Percent Difference Interpretation
Average is equal to or greater than  0.02 WL Less than 36% Results can be used even if Relative Percent Difference is greater than 36% since both results are above 0.02WL.
Average is less than 0.02 WL Less than 67% Results can be used even if Relative Percent Difference is greater than 67% since both results are below 0.02WL.
One result exceeds 0.02 WL and the other is below 0.02 WL The higher value should not be more than twice the lower value If the higher value is more than twice the lower value the test should be repeated.

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Last modified: 06/05/08