Current through Register Vol. 54, No.43, October 26, 2024
Section 240.606 - QA requirements for laboratories(a)CRMs for laboratories.(1)Calibration. Each Department-listed CRM must have a current calibration. To have a current calibration, the CRM shall be calibrated in a Department-approved calibration facility within 1 year from the date of the previous calibration and when alterations or repairs are made to the CRM. A current calibration certificate shall be retained for each monitor. Analysis may not be performed on a monitor that was not calibrated during any portion of the testing period.(2)Data collection log. CRM data shall be tracked on a form that contains all of the following: (i) The CRM serial number.(ii) The exposure dates and times.(iv) The address of the building tested.(v) The test location in the building.(vi) The name of the tester who placed the CRM.(vii) The name of the tester who retrieved the CRM.(viii) The calibration, repair and Department listing dates.(b)CWLM for laboratories.(1)Calibration. Each Department-listed CWLM must have a current calibration. To have a current calibration, the CWLM shall be calibrated in a Department-approved calibration facility within 1 year from the date of the previous calibration and when alterations or repairs are made to the CWLM. A current calibration certificate shall be retained for each monitor. Analysis may not be performed on a monitor that was not calibrated during any portion of the testing period.(2)Data collection log. CWLM data shall be tracked on a form that contains all of the following: (i) The CWLM serial number.(ii) The exposure dates and times.(iv) The address of the building tested.(v) The test location in the building.(vi) The name of the tester who placed the CWLM.(vii) The name of the tester who retrieved the CWLM.(viii) The calibration, repair and Department listing dates.(c)Electret ion chamber for laboratory analysis.(1)Calibration. Each Department-listed electret reader shall have a current calibration. To have a current calibration, the electret reader shall be calibrated in a Department-approved calibration facility within 1 year from the date of the previous calibration and when alterations or repairs are made to the electret reader. Each electret reader shall be calibrated simultaneously with its corresponding reference electret's recertification.(2)Voltmeter routine instrument checks.(i) Proper operation of the surface voltmeter shall be monitored following the manufacturer's procedures for zeroing the voltmeter and analyzing the reference electrets.(ii) A voltage reading of a reference electret difference of more than 2 volts from its specified value shall be considered a wrong reading and corrective action shall be taken.(iii) If the voltmeter displays more than (±) 3 volts, corrective action shall be taken.(iv) Voltmeter checks shall be conducted at least once each week while the voltmeter is in use and shall be documented. Documentation of routine instrument checks must include all of the following: (A) The reader serial number.(B) The date of analysis.(D) The reference electret values.(E) Corrective actions performed.(3)Known exposure measurements (spikes).(i) Spikes shall be conducted at a rate of 3 for each 100 test devices deployed, with a minimum of 3 spikes for each certification year when tests were conducted in the certification year, and with a maximum of 6 spikes each month.(ii) Spikes shall be analyzed in the same manner as all other testing.(iii) Spikes shall be monitored using a means control chart. The means control chart must be established as follows: (A) Using an RPE value of plus and minus 10%, which corresponds to the 1 sigma level.(B) A warning level of the RPE of plus and minus 20%, which corresponds to the 2 sigma warning level.(C) Control limits of the RPE of plus and minus 30%, which correspond to the 3 sigma control level.(iv) Each RPE value shall be plotted on the means control chart within 1 week of return of the device from the radon chamber. If the RPE value is outside the 3 sigma control level, all measurements shall cease until the problem is evaluated and corrected. All evaluations shall be documented.(v) In addition to the means control chart, all spikes shall be documented on a form that contains all of the following: (A) The radon chamber name.(B) The electret serial numbers.(C) The RV from the radon chamber.(D) The measured spike value or values.(E) The individual RPE results.(F) The certification year beginning date and end date.(4)Duplicate measurements.(i) Duplicates shall be made in at least 10% of the total number of test devices deployed each month, or 50 each month, whichever is smaller.(ii) The RPD shall be calculated for all duplicate results with an average of greater than or equal to 2.0 pCi/L. Two control charts shall be constructed to monitor duplicate precision:(A) One for duplicates when the average is greater than or equal to 4.0 pCi/L.(B) One for duplicates when the average is greater than or equal to 2.0 pCi/L and less than 4.0 pCi/L.(iii) Each RPD value shall be plotted on the control chart within 1 week of performing the duplicate measurement.(iv) The RPD shall be tracked using control charts from "Protocols for Radon and Radon Decay Product Measurements in Homes," EPA 402-R-92-003, May 1993, Appendix B, Exhibits B-2 and B-3.(v) For duplicates when the average is greater than or equal to 4.0 pCi/L, all of the following apply: (A) The control level shall be set at an RPD of 14%.(B) The warning level shall be set at an RPD of 28%.(C) The control limit shall be set at an RPD of 36%.(vi) For duplicates when the average is greater than or equal to 2.0 pCi/L and less than 4.0 pCi/L, all of the following apply:(A) The control level shall be set at an RPD of 25%.(B) The warning level shall be set at an RPD of 50%.(C) The control limit shall be set at an RPD of 67%.(vii) If the plotted RPD result falls outside of the control limit, the measurements shall cease until the problem is identified and corrected.(viii) If the plotted RPD result falls outside of the warning level, "Protocols for Radon and Radon Decay Product Measurements in Homes," EPA 402-R-92-003, May 1993, Appendix B, Exhibit B-5, shall be used to determine the action to be taken.(ix) Documentation of duplicates must include all of the following:(A) The device serial numbers.(C) Each duplicate measurement result.(d)AC and LS.(1)Calibration. All AC or LS laboratory systems shall be calibrated at least once every 12 months, when alterations or repairs are made to the system, or when a new batch of charcoal is received. This requires a determination of calibration factors for AC and LS devices by the exposure of these devices to a known concentration of radon in a Department-approved radon chamber. Calibration factors shall be determined for a range of exposure times and humidity levels.(2)Laboratory control devices. The laboratory background level for each batch of AC and LS devices shall be established by each laboratory. Laboratories shall measure the background of at least 5% of unexposed AC and LS devices that have been processed according to their standard operating procedures (laboratory blanks).(3)Routine counting system checks. Daily counting of a reference source shall be performed and documented. The characteristics of the check source (geometry, type of radiation emitted, and the like) must be similar to the samples to be analyzed. The count rate of the check sources must be high enough to yield reliable counting statistics in a short period of time, such as 1,000 to 10,000 counts per minute, to provide a maximum random uncertainty of 5%.(4)Known exposure measurements (spikes).(i) Spikes shall be conducted at a rate of 3 for each 100 test devices deployed, with a minimum of 3 spikes for each certification year when tests were conducted in the certification year, and with a maximum of 6 spikes each month.(ii) Spikes shall be analyzed in the same manner as all other testing.(iii) Spikes shall be monitored using a means control chart. The means control chart must be established as follows:(A) Using an RPE value of plus and minus 10%, which corresponds to the 1 sigma level.(B) A warning level of the RPE of plus and minus 20%, which corresponds to the 2 sigma warning level.(C) Control limits of the RPE of plus and minus 30%, which correspond to the 3 sigma control level.(iv) Each RPE value shall be plotted on the means control chart within 1 week of receiving the result from the laboratory. If the RPE value is outside the 3 sigma control level, all measurements shall cease until the problem is evaluated and corrected. All evaluations shall be documented.(v) In addition to the means control chart, all spikes shall be documented on a form that contains all of the following: (A) The radon chamber name.(B) The device serial numbers.(C) The RV from the radon chamber.(D) The measured spike value or values.(E) The individual RPE results.(F) The certification year beginning date and end date.(5)Duplicate measurements.(i) Duplicates shall be made in at least 10% of the total number of test devices deployed each month, or 50 each month, whichever is smaller.(ii) The RPD shall be calculated for all duplicate results with an average of greater than or equal to 2.0 pCi/L. Two control charts shall be constructed to monitor duplicate precision:(A) One for duplicates when the average is greater than or equal to 4.0 pCi/L.(B) One for duplicates when the average is greater than or equal to 2.0 pCi/L and less than 4.0 pCi/L.(iii) Each RPD value shall be plotted on the control chart within 1 week of performing the duplicate measurement.(iv) The RPD shall be tracked using control charts from "Protocols for Radon and Radon Decay Product Measurements in Homes," EPA 402-R-92-003, May 1993, Appendix B, Exhibits B-2 and B-3.(v) For duplicates when the average is greater than or equal to 4.0 pCi/L, all of the following apply: (A) The control level shall be set at an RPD of 14%.(B) The warning level shall be set at an RPD of 28%.(C) The control limit shall be set at an RPD of 36%.(vi) For duplicates when the average is greater than or equal to 2.0 pCi/L and less than 4.0 pCi/L, all of the following apply:(A) The control level shall be set at an RPD of 25%.(B) The warning level shall be set at an RPD of 50%.(C) The control limit shall be set at an RPD of 67%.(vii) If the plotted RPD result falls outside of the control limit, the measurements shall cease until the problem is identified and corrected.(viii) If the plotted RPD result falls outside of the warning level, "Protocols for Radon and Radon Decay Product Measurements in Homes," EPA 402-R-92-003, May 1993, Appendix B, shall be used to determine the action to be taken.(ix) Documentation of duplicates must include all of the following:(A) The device serial numbers.(C) Each duplicate measurement result.(e)ATs.(1)Calibration. All AT laboratory systems shall be calibrated at least once every 12 months, when alterations or repairs are made to the system, or when each new batch or sheet of detector material is received. This requires a determination of calibration factors for AT devices by the exposure of these devices to different concentrations of radon in a Department-approved radon chamber.(2)Laboratory control detectors. Laboratory control detectors for each batch of ATs shall be established and documented. Each laboratory shall measure the background of a statistically significant number of unexposed ATs. The laboratory control background value shall be subtracted from the field readings to produce a final result.(3)Known exposure measurements (spikes).(i) Spikes shall be conducted at a rate of 3 for each 100 test devices deployed, with a minimum of 3 spikes for each certification year when tests were conducted in the certification year, and with a maximum of 6 spikes each month.(ii) Spikes shall be analyzed in the same manner as all other testing. The RV of a spike may not be revealed to the laboratory prior to analysis.(iii) Spikes shall be monitored using a means control chart. The means control chart must be established as follows:(A) Using an RPE value of plus and minus 10%, which corresponds to the 1 sigma level.(B) A warning level of the RPE of plus and minus 20%, which corresponds to the 2 sigma warning level.(C) Control limits of the RPE of plus and minus 30%, which correspond to the 3 sigma control level.(iv) Each RPE value shall be plotted on the means control chart within 1 week of receiving the result from the laboratory. If the RPE value is outside the 3 sigma control level, all measurements shall cease until the problem is evaluated and corrected. All evaluations shall be documented.(v) In addition to the means control chart, all spikes shall be documented on a form that contains all of the following: (A) The radon chamber name.(B) The device serial numbers.(C) The RV from radon chamber.(D) The measured spike value or values.(E) The individual RPE results.(F) The certification year beginning date and end date.(4)Duplicate measurements.(i) Duplicates shall be made in at least 10% of the total number of test devices deployed each month, or 50 each month, whichever is smaller.(ii) The RPD shall be calculated for all duplicate results with an average of greater than or equal to 2.0 pCi/L. Two control charts shall be constructed to monitor duplicate precision:(A) One for duplicates when the average is greater than or equal to 4.0 pCi/L.(B) One for duplicates when the average is greater than or equal to 2.0 pCi/L and less than 4.0 pCi/L.(iii) Each RPD value shall be plotted on the control chart within 1 week of performing the duplicate measurement.(iv) The RPD shall be tracked using control charts from "Protocols for Radon and Radon Decay Product Measurements in Homes," EPA 402-R-92-003, May 1993, Appendix B, Exhibits B-2 and B-3.(v) For duplicates when the average is greater than or equal to 4.0 pCi/L, all of the following apply: (A) The control level shall be set at an RPD of 14%.(B) The warning level shall be set at an RPD of 28%.(C) The control limit shall be set at an RPD of 36%.(vi) For duplicates when the average is greater than or equal to 2.0 pCi/L and less than 4.0 pCi/L, all of the following apply:(A) The control level shall be set at an RPD of 25%.(B) The warning level shall be set at an RPD of 50%.(C) The control limit shall be set at an RPD of 67%.(vii) If the plotted RPD result falls outside of the control limit, the measurements shall cease until the problem is identified and corrected.(viii) If the plotted RPD result falls outside of the warning level, "Protocols for Radon and Radon Decay Product Measurements in Homes," EPA 402-R-92-003, May 1993, Appendix B, Exhibit B-5, shall be used to determine the action to be taken.(ix) Documentation of duplicates shall include all of the following:(A) The device serial numbers.(C) Each duplicate measurement result.