• Power Supply: Transformer converts 120 VAC to 12 VDC. Optional 220 VAC power supply available


• Sensitivity: 2.5 counts per hour per picocurie per liter


• Measurement Range: 0.1 to 999 picocuries/liter (pCi/l)


• Operating Range: 45 degrees F to 95 degrees F


• Accuracy: ±20% NRSB


• Detector: Diffused-junction photodiode


• Measurement Intervals: 1 hour


• Data Port: RS-232 9 pin D connector allows printer data to be sent to PC


• Battery Backup: One 9 V alakaline battery supplies 24 our operation. LED indicated low battery


• Tilt Switch: Disturbance Detector


• Weight: 2 lbs


• Size: 8" * 4.7" * 2.5"


• Display: 3 digit LED display


• Displayed Values:
  Long-term average- Accumulates until device is reset.
  Short-term average- rolling  12 hour average


• Key Lock: Inhibits tampering with the device


• EPA Evaluation: US EPA accepted

Q: Why do the hourly readings on my radon monitor always seem to show the same numbers (such as 0.0, 0.3, 0.7, etc.), especially at lower radon levels? Why doesn’t it measure values between these numbers, such as 0.5? Does this mean there is something wrong with my monitor?
A: There is nothing wrong with the monitor. The reason the same set of numbers appear is because the number of alpha particle counts is so low. At very low radon levels, only one, two, or even zero radon-emitted alpha particles may be detected in an hour interval. A typical one-detector SNC radon monitor, such as a model 1027 or 1028, has a sensitivity roughly in the range of 3.0 counts per hour per pCi/L (individual monitors may have higher or lower sensitivities – check your calibration factor for the actual number). If only one count is detected in an hour, this means that the monitor has measured 1 cph / 3.0 cph per pCi/L = 0.3333 pCi/L, which is rounded to 0.3. Two counts would mean 0.6666 pCi/L, which would round to 0.7. It will not measure an hourly value like 0.5, because this would mean that it has measured something like one and a half counts, something it cannot do because of the quantized nature of radiation. However, because radon measurements are generally performed over a longer time period, such as 48 hours, the average of many of these discrete hourly measurements is capable of measuring any value, even at low radon levels. So a radon level of 0.5 pCi/L measured over 48 hours might have individual hourly measurements of 0.0, 0.3, 0.7, or 1.2, but the average of all 48 hourly measurements would still read 0.5 pCi/L.

Q: What type of cable is used for communication between a 1027 and PC?
A: The cable is a standard "9-pin D" Serial Extension Cable. A USB adapter cable (p/n 850029) is available for purchase upon request.

Q: Do I have to run the software (log.exe) from the CD?
A: YES, or you can copy all the files from the CD to your computer hard drive and run the software from that location.

Q: What test results are invalid and may indicate a problem with the Radon Monitor?
A: Following are the printouts that display test results that are invalid and may indicate a problem with the Sun Nuclear Radon Monitor. If you encounter similar test results then please contact Sun Nuclear Technical Support for further assistance.

Figure 1
The test results show that all the hourly averages were 0.0 pCi/1. Note that hourly averages of 0.0 pCi/1 are possible when testing a low concentration area but is unlikely over a consecutive time period.

Figure 2
The test result shows a group of hourly averages that were 0.0 pCi/1 but the rest of the test shows normal results. As stated above hourly averages of 0.0 pCi/1 are possible when testing a low concentration area but is unlikely over a consecutive time period.

Figure 3
The test results show a group of hourly averages that were 0.0 pCi/1 and other values that fluctuate greatly.

Q: How do I retrieve the radon monitor data after the test is completed?
A: To stop the test, turn the battery backup switch to the off position and disconnect the power adapter from the monitor and the wall outlet . As long as there is no power supplied to the radon monitor then it will not collect any new data. The data will not be erased until the user clears the monitor's memory. You can print the information at the test site or download later.

Q: Can I print the data from the monitor more than once without losing the data?
A: Yes, you can print or transmit the data to a PC as many times as you want. The data is only erased when the user clears the monitor's memory.

Q: What does a "T" indicate on the printout?
A: A "T" on the printout indicates that the monitor was moved during that hour of operation.

Q: What does a "P" indicate on the printout?
A: A "P" on the printout indicates that the monitor lost complete power from both the power adapter and backup battery.

Q: I ran a 150 hour test with a radon monitor but there was only 90 hourly averages on the printout. Where is the rest of the data?
A: The radon monitor has a storage limit of 90 data points. The first 90 hourly averages are stored for the printout. The printed overall average will still reflect the 150 hour test period.

Q: What is the difference between the OVERALL average and the EPA Protocol average?
A: The EPA Protocol average does NOT include the first 4 hours of data in the calculation. The EPA considers the first 4 hours as a warm up or equilibrium period for the radon.

Q: How do I change the time interval for the printed report so that each data point represents a 4 hour average instead of a 1hour average?
A: The Model 1027 is shipped from the factory, set to store a radon gas measurement every one hour during a test period. The monitor may be set to store a measurement value each hour, every 4 hours, every 8 hours or every 24 hours. The Model 1027 is capable of storing 90 interval measurements for any given test period. These measurement values reflect the first 90 intervals from the start of the test. Once all 90 points are stored, no more data points will be collected, even though the test period may continue. It is important to note that the AVERAGE value continues to collect measurement information, and the final AVERAGE value reflects the entire test period, independent of the total length of time. The interval selection is determined, to some extent, by the total period of the test. When set to store data values each hour, the longest test period that can be made and have periodic data will be 90 hours. While a data interval of four hours will give periodic data points for a total test period of 90 x 4, or 360 hours, and so on. The data interval is set by an internal dip-switch. The Model 1027 must be physically opened in order to gain access to the dip-switch. The procedure is as follows:

*************************************

WARNING: High Voltage Inside
Disconnect power (Power Converter and Battery),
Wait 30 minutes before removing the cover.

*************************************

(See Above Warning) With the key side facing you, remove the four screws on both ends of the Model 1027. You should be able to find the tamper proof tips at local hardware stores.
Lift the cover, making certain the battery ON-OFF switch is free, and rotate the cover away from you letting it come to rest upside down above the battery compartment side of the base.
The electronics are now visible in the upside down cover, in the lower right corner you will see a four position dip-switch.
The switch positions are numbered 1 through 4, the switch will have labels which will identify which side is OFF and/or ON. On one side of the switch are interval values printed on the circuit board. Position Interval 1 (1 hr), 2 (4 hrs), 3 (8 hrs), 4 (24 hrs).
Select the switch position for the interval desired, and shift it to the ON position. Make certain to shift the previously selected interval to the OFF position; only one switch should be in the ON position at any time.
The new data interval has now been selected, however, this interval will not actually be used by the monitor until a memory CLEAR procedure is completed. After the first memory CLEAR, all subsequent tests will use the selected interval.
Reassemble the monitor by reversing the earlier steps.

Q: How can I learn more about the technology and theory of operation for the Model 1027?
A: Click here to download a PDF document that discusses these topics on an in-depth and technical basis

Q: My thermal printer settings are incorrect.  How can I set them to the original factory settings?
A: Users can modify the thermal printer settings that are set at the factory.  Doing so may cause the printer to function improperly.  Click here for instructions on how to return the thermal printer settings to the factory settings.

Q: Do you provide a sample Radon Measurement Report?
A: Yes. Choose either link below to download a form for reporting the results of Radon Testing with our Radon Monitors to clients.

PDF format (41k): RadonRpt.pdf      Word Document (22k): RadonRpt.doc