Semiannual Maintenance and Calibration Report Prepared by Air Resource Specialists, Inc.

Semiannual Maintenance and Calibration Report Prepared by Air Resource Specialists, Inc. Client: National Park Service Field Personnel: Mike Farinacci Site: Island in the Sky (CANY-IS) Service Date(s): /29/26 Site Operator: Cody Marsh Subject: Semiannual Maintenance All site visit and calibration forms are attached, detailing the pre- and post-maintenance calibrations and test results. SUMMARY OF FINDINGS GASEOUS POLLUTANT SUPPORT EQUIPMENT Zero-Air System (Werther / Panther Compressor PC7/4E): Maintenance - No maintenance for the pump or compressor was required at this time. The media for the zero-air system was replaced. Station Temperature: Pre-Maintenance Testing - The sensor was compared against a certified temperature transfer standard. The sensor was found to be responding outside of calibration acceptance criteria. Maintenance - There was a -3.5 offset on the STP channel, which was removed. Post-Maintenance Testing - The sensor was compared against a certified temperature transfer standard. The sensor was found to be responding within calibration acceptance criteria. GASEOUS POLLUTANT ANALYZERS Ozone Analyzer (Thermo 49i): Pre-Maintenance Testing - The ozone analyzer was compared against a Level 2 ozone transfer standard. The ozone analyzer was found to be responding within calibration acceptance criteria. Maintenance - Cooling fan filter was cleaned and the instrument was calibrated at 2 ppb. Post-Maintenance Testing - The ozone analyzer was compared against a Level 2 ozone transfer standard. The ozone analyzer was found to be responding within calibration acceptance criteria. Ozone Station Reference (Thermo 49i): Pre-Maintenance Testing - The Level 3 ozone station reference was recertified using a Level 2 ozone transfer standard. The ozone station reference was found to be responding within calibration acceptance criteria. Maintenance - New coefficients were entered in the datalogger to reflect the updated certification. Post-Maintenance Testing - The ozone station reference was compared against a Level 2 ozone transfer standard. The ozone station reference was found to be responding within calibration acceptance criteria.

METEOROLOGICAL SENSORS Ambient Temperature and Vertical Temperature Difference (RM Young 4342VC): Pre-Maintenance Testing - The sensor was compared against a certified temperature transfer standard in three water baths controlled at temperatures between and 5 degrees Celsius. The sensor was confirmed to be responding within calibration acceptance criteria. The aspirator fan was functioning correctly. Maintenance - No maintenance was performed. Post-Maintenance Testing - No post-maintenance checks were performed. Relative Humidity (Rotronic MP6): Pre-Maintenance Testing - The sensor was collocated with a certified relative humidity transfer standard. The sensor was confirmed to be responding within calibration acceptance criteria. The aspirator fan was functioning correctly. Maintenance - The sensor was swapped with a laboratory certified sensor. Post-Maintenance Testing - The sensor was collocated with a certified relative humidity transfer standard. The sensor was confirmed to be responding within calibration acceptance criteria. Wind Speed (Climatronics 75): Pre-Maintenance Testing - The sensor was challenged with a certified anemometer drive. The sensor was confirmed to be responding within calibration acceptance criteria. The starting threshold test for the sensor was within acceptance criteria. The heater for the sensor was found to be functioning correctly. Maintenance - The sensor was swapped with a laboratory rebuilt sensor. Post-Maintenance Testing - The sensor was challenged with a certified anemometer drive. The sensor was confirmed to be responding within calibration acceptance criteria. The starting threshold test for the sensor was within acceptance criteria. The heater for the sensor was functioning correctly. Wind Direction (Climatronics 76): Pre-Maintenance Testing - The reference alignment for the sensor was checked using a compass. The reference alignment for the sensor was confirmed to be within acceptable limits. The accuracy of the sensor was tested by comparison to a reference. The sensor was confirmed to be responding within calibration acceptance criteria. The linearity of the sensor was within acceptable limits. The starting threshold test results were within acceptance criteria. The heater for the sensor was confirmed to be functioning correctly. Maintenance - The sensor was swapped with a laboratory rebuilt sensor. Post-Maintenance Testing - The reference alignment for the sensor was checked using a compass. The reference alignment for the sensor was confirmed to be within acceptable limits. The accuracy of the sensor was tested by comparison to a reference. The sensor was confirmed to be responding within calibration acceptance criteria. The linearity of the sensor was within acceptable limits. The starting threshold test for the sensor was within acceptance criteria. The heater for the sensor was functioning correctly.

Solar Radiation (Li-Cor Pyranometer): Pre-Maintenance Testing - The sensor was collocated with a certified solar radiation transfer standard. The sensor was confirmed to be responding outside of calibration acceptance criteria. (SELECT) Maintenance - The sensor was re-leveled and the zero was calibrated on the Climatronics translator. The solar levels were very low during this visit. A shunted sensor will be installed during the next SAM visit. Post-Maintenance Testing - The sensor was collocated with a certified solar radiation transfer standard. The sensor was confirmed to be responding outside of calibration acceptance criteria. Precipitation (Climatronics 58): Pre-Maintenance Testing - The sensor was challenged using a known volume of water. The sensor was found responding within calibration acceptance criteria. The sensor was found to be level and clean. The heater was found to be functional. Maintenance - No maintenance was performed. Post-Maintenance Testing - No post-maintenance checks were performed. PARTICULATE MONITORS AND SAMPLERS CASTNET Filter Pack Flow: Pre-Maintenance Testing - A leak check on the system was performed and results were within acceptable limits. The flow was checked using a certified flow standard measuring flow in standard conditions. The measured flow was found to be within calibration acceptance criteria. Maintenance - The balston filter was replaced, the brass elbow was cleaned, and the pump diaphragm was replaced. No calibration was performed. Post-Maintenance Testing - The flow was checked using a certified flow standard measuring flow in standard conditions. The measured flow was confirmed to be within calibration acceptance criteria. ADDITIONAL COMMENTS The site is in good condition.

SITE INFORMATION ABBR. CANY-IS SITE NAME NETWORK TYPE CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 Island in the Sky DATE OF LAST VISIT 5/4/26 NPS Deg Min Sec LATITUDE North 38 27 32 LONGITUDE West 9 49 6.5 --CALCULATE-> Decimal 38.4589 9.823 Decimal Deg Min Sec --CALCULATE-> ELEVATION Meters --CALCULATE-> Feet Feet 5869 --CALCULATE-> Meters 789 Photo Documentation Completed? Yes No N/A Cellular Phone Coverage Cellular Phone Coverage Protocol? Carrier? # of Bars? Signal Strength? -X dbm -X dbm DAY TIME IN TIME OUT /29/26 95 75 SITE STANDARDS PM Flow Reference Please verify site standards used by the site operator MANUFACTURER MODEL SERIAL # Calibration Expiration Date NOTES:

TEMPERATURE / VERTICAL TEMPERATURE DIFFERENCE SYSTEM VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS MANUFACTURER MODEL SERIAL NUMBER EXPIRATION DATE Temperature Reference Eutechnics 44 38286 9/8/27 2m Temperature Sensor Climatronics 88-2 578 List sensors according to height on tower, from highest to lowest. Climatronics 88-2 578 Temp. Deltas CALIBRATION ACCEPTANCE CRITERIA (<=) Ambient Temperature Difference ( o C).5 Vertical Temperature Difference ( o C) N/A 2m Temperature Bath Temp ( o C) DAS Difference.3.6.3 24.3 24.6 -.4 4.76 4.5.29 MAX ABS Difference.29 MAX ABS Difference Aspirator fan functional 2m? Yes No N/A Yes No N/A Yes No N/A Yes No N/A Each sensor was verified against its data channel? Yes No N/A Each Temperature Difference = Upper - Lower? Yes No N/A Bath Temp ( o C) MAX ABS Difference MAX ABS Difference NOTES:

STATION TEMPERATURE SENSOR VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE SITE NAME Island in the Sky DATE OF LAST VISIT Network type NPS /29/26 5/4/26 Temperature Reference MANUFACTURER Eutechnics MODEL SERIAL NUMBER 44 38286 EXPIRATION DATE 9/8/27 CALIBRATION ACCEPTANCE CRITERIA (<=) Temperature Difference ( o C). Temperature Temperature Reference ( o C) DAS ( o C) Difference Reference ( o C) DAS ( o C) Difference 23.6 2.7-2.5 FAIL 24.77 25.33.6 NOTES: -3.5 offset was removed from STP channel.

RELATIVE HUMIDITY SENSOR VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE SITE NAME Island in the Sky DATE OF LAST VISIT Network type NPS /29/26 5/4/26 RH SENSOR REFERENCE MANUFACTURER Vaisala MODEL HMP55 SERIAL NUMBER G2837 EXPIRATION DATE 4/5/27 Rotronic MP6 5269 Rotronic MP6A 5264 FIELD CALIBRATION ACCEPT. CRITERIA (<=) Relative Humidity Difference (%) 5% Hour 2 3 Relative Humidity (%) Relative Humidity (%) STD DAS Difference V Hour STD DAS Difference 49.% 52.% 2.9% 4 4.% 42.7%.7% 42.2% 44.9% 2.7% 5 46.6% 49.% 2.5% 42.2% 44.6% 2.4% 6 54.3% 56.8% 2.5% V Average 2.7% Average 2.2% Aspirator fan functional? Yes No N/A NOTES: Sensor was swapped.

WIND SPEED SENSOR VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS MANUFACTURER MODEL SERIAL NUMBER EXPIRATION DATE Wind Speed Reference RM Young 882 CA 3628 4/8/27 Wind Speed Torque Gauge RM Young 83 n/a and Climatronics - 75 / and Climatronics - 75 / Heavy Duty Aluminum Heavy Duty Aluminum Sensor Serial # 478 Sensor Serial # 284 Cups Serial # 44 Cups Serial # 44 CALIBRATION ACCEPTANCE CRITERIA (<=) Wind Speed Difference (m/s) Wind Speed Difference (%).25 5.% if wind speed <= 5 m/s if wind speed > 2 m/s Wind Speed Threshold (m/s vs % Diff.) 5. 2. Select UNITS m/s Motor Speed (rpm) Target Speed. 3 7.274 6 4.325 9 2.375 2 28.426 8 42.527 Wind Speed DAS Difference.93 N/A N/A N/A 7.36 -.9% 4. -.6% 2.6 -.5% 28.5 -.3% 4.99 -.3% Starting Threshold Torque <=.3 g-cm TORQUE.3 NO ACTION REQUIRED Heater sleeve functional? Yes No N/A Wind Speed Motor Speed (rpm) Target Speed DAS Difference..99 N/A N/A N/A 3 7.274 7.47 -.7% 6 4.325 4.9 -.6% 9 2.375 2.6 -.5% 2 28.426 28. -.5% 8 42.527 4.92 -.4% Starting Threshold Torque <=.3 g-cm TORQUE.3 NO ACTION REQUIRED NOTES: Sensor was swapped.

WIND DIRECTION SENSOR VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS Direction Alignment Reference Direction Linearity Reference Direction Torque Gauge MANUFACTURER MODEL SERIAL NUMBER Brunton Transit 584258 Wilson Machining 8 pt jig 85 RM Young 83 n/a EXPIRATION DATE & Sensor Serial # Vane Serial # Climatronics - 76 & Climatronics - 76 2228 Sensor Serial # #2 35 Vane Serial # 35 Local Magnetic Declination (degrees). Method Solar Azimuth CALIBRATION ACCEPTANCE CRITERIA (<=) Cross-arm Alignment Error (degrees) 2 Total Align. Diff (degrees) 5 Sensor Linearity (degrees) 5 Mag. Dec. from NOAA (deg/min/sec) Landmarks From the North From the South From the East From the West 23 3.39 http://www.ngdc.noaa.gov/geomag-web/#declination Degrees 8 9 27 Is the Reference Alignment intended to be N-S? YES Is the Reference Alignment intended to be N-S? YES Reference Alignment (degrees) 358. Reference Alignment (degrees) 358. SENSOR ALIGNMENT N-S Reference Degrees DAS From the North 36.5 From the South 8 82.2 From the East 9 448.5 From the West 27 272.3 Total Alignment MAX ABS Diff OR SENSOR ALIGNMENT N-S Reference Degrees DAS From the North 357.6 From the South 8 82.5 From the East 9 448. From the West 27 269.9 Total Alignment MAX ABS Diff SENSOR ALIGNMENT SENSOR ALIGNMENT Landmark Degrees DAS Difference Landmark Degrees DAS Difference From the North From the North From the South 8 From the South 8 From the East 9 From the East 9 From the West 27 From the West 27 Total Alignment MAX ABS Diff Total Alignment MAX ABS Diff OR Difference.5 2.2 -.5 2.3 4.3 SENSOR ALIGNMENT SENSOR ALIGNMENT X Reference Degrees DAS Difference X Reference Degrees DAS 358 Align with Ref (N) 358 538 Align with Ref (S) 538 448 Perp with Ref (E) 448 628 Perp with Ref (W) 628 Total Alignment MAX ABS Diff Total Alignment MAX ABS Diff OR OR Difference -2.4 2.5-2. -. 4.5 Difference SENSOR LINEARITY Point DAS Difference 489.5 N/A 2 77.5 3 3 223.2 4 267.9 5 32.8 6 358. 7 4.5-2 8 446. - 489.5-2 MAX Difference 3 SENSOR LINEARITY Point DAS Difference 33.3 N/A 2 348. 3 39.7-4 436.7 5 48.4 6 69.2 3 7 24.3 8 259.2 33.4 - MAX Difference 3 NO ACTION REQUIRED NO ACTION REQUIRED Starting Threshold TORQUE Starting Threshold Torque <= 6. g-cm 5.3 Torque <= 6. g-cm NO ACTION REQUIRED TORQUE 5.3 NO ACTION REQUIRED Heater sleeve functional? Yes No N/A NOTES: Sensor was swapped.

SOLAR RADIATION SENSOR VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT Network type NPS 5/4/26 Solar Radiation Reference MANUFACTURER MODEL SERIAL NUMBER EXPIRATION DATE Licor Pyranometer PY 83379 /5/27 MULTIPLIER 2. Translator Logger Type ESC Licor Pyranometer PY 46778 Climatronics High Input (V) 5. Low Input (V). High Output 396. Low Output. Licor Pyranometer PY 46778 Translator Climatronics Logger Type High Input (V) 5. ESC Low Input (V). High Output 396. Low Output. CALIBRATION ACCEPTANCE CRITERIA (<=) Difference from CTS (%) % Solar Radiation Hour CTS (W/m 2 ) DAS (W/m 2 ) Difference 27. 287 6.2% 2 337.2 357 5.8% 3 2.6 22 4.3% V DARK RESPONSE DAS (W/m 2 ) MEAN ABS % DIFF 5.4% ACTION Sensor found clean? Yes No Sensor found level? Yes No Solar Radiation DAS (W/m 2 ) Hour CTS (W/m 2 ) 4 33.9 336 24.3 25 53.6 64 Difference 7.2% 5.% 6.5% V DAS (W/m 2 ) DARK RESPONSE MEAN ABS % DIFF 6.2% ACTION NOTES: Sensor level was adjusted, zero was calibrated. Low solar levels and clouds prevented a valid check after sensor was leveled and zero calibrated.'

PRECIPITATION SENSOR VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS MANUFACTURER MODEL SERIAL NUMBER Precipitation Reference Texas Electronics FC-525 n/a EXPIRATION DATE Climatonics 58 NPS 987 Climatonics 58 CALIBRATION ACCEPTANCE CRITERIA (<=) Difference from Input Volume (%) 5% x Reference Chart Input Volume (ml) Climatronics Climatronics Met One 97--G-H 58 37 Diameter (in.) 8 9.66 8 mm/tip.254..254 ml/tip 8.24 4.73 8.24 Met One 385 2.254 8.53 RM Young 5222 6.2825. 2. Texas Electronics TR-525I-HT 6.6.254 4.73 94 DAS target 28.99 9.88 28.99 2.88 47. 5.52 Conversions Value Units Value. inch 25.4 25.4 mm. Units mm inch Reference (ml) Target (mm) 94 9.88 Precipitation DAS (mm) Difference 9.2-3.4% Heater functional? Yes No N/A Sensor found level? Yes No Sensor found clean? Yes No Precipitation Reference (ml) Target (mm) DAS (mm) Difference 94 NOTES:

CASTNET FLOW SYSTEM VERIFICATION & CALIBRATION ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS MFC High Flow Reference MANUFACTURER MODEL SERIAL NUMBER BIOS Definer 22-H 2694 EXPIRATION DATE 2/8/27 MFC Tylan FC-28 AW94322 MFC Tylan FC-28 AW94322 Pump Flow Target 3. Thomas 7CAB8A 682A ENTER FLOWS IN SLPM Pump Thomas 7CAB8A 682A MFC Display Linear MFC VDC Linear Regression Regression Date 5/3/26 Setpoint Slope Intercept 2.77.757.658 Setpoint Slope Intercept 2.838.58 -. ESC Logger Scaling High Input (V) Low Input (V) High Output (LPM) Low Output (LPM) 5.. 5.452 -.29 Operational Checks Vacuum DAS Flow MFC Flow Flow Standard Target 8. 3. 2.8 3. Flow Standard Rotometer MFC Display MFC Volts DC DAS Display Difference Value % Pump Off. SLPM. -.2.24.5 Leak Test. SLPM...3.6 2. SLPM.929 2..76.765.92 -.27 -.4% 2 (low) 2.5 SLPM 2.54 2.8 2.3 2.32 2.53 -.28 -.% 3 (target) 3. SLPM 3.4 3.4 2.77 2.778 3.5 -.26 -.9% 4 (high) 3.5 SLPM 3.795 4. 3.45 3.46 3.765 -.3 -.8% 5 4. SLPM 4.95 4.6 3.82 3.825 4.58 -.37 -.9% MAX > 4. SLPM 4.573 5. 4.6 4.72 4.537 -.36 -.8% Leak Test Results Flow (SLPM).3 *Note: A leak is present if the difference between the zero and leak test value is greater than. lpm Recalibration Not Required *Note: A calibration is required if the difference between the transfer standard and the DAS value is greater than +/- 2.% at the target setting or greater than +/- 2.5% at either the low or high point NEW CALIBRATION FACTORS MFC Display Linear MFC VDC Linear Regression Regression ESC Logger Scaling Setpoint 2.73 Setpoint 2.739 High Input (V) 5. Slope. Slope. Low Input (V). Intercept -.5 Intercept -.4 High Output (LPM) 5.489 Correlation. Correlation. Low Output (LPM) -.4 Target Flow Standard Rotometer MFC Display MFC Volts DC DAS Display Value % Pump Off. SLPM. -..6. Leak Test. SLPM...28.3 2. SLPM 2.8 2.2.82.833.98 -.28 -.4% 2 (low) 2.5 SLPM 2.48 2.7 2.25 2.26 2.448 -.32 -.3% 3 (target) 3. SLPM 3.43 3.3 2.75 2.767 3.2 -.4 -.3% 4 (high) 3.5 SLPM 3.553 3.8 3.2 3.222 3.56 -.47 -.3% 5 4. SLPM 4.22 4.5 3.72 3.73 4.62 -.6 -.5% MAX > 4. SLPM 4.75 5. 4.28 4.292 4.67 -.79 -.7% Leak Test Results Flow (SLPM).2 *Note: A leak is present if the difference between the zero and leak test value is greater than. lpm Operational Checks Vacuum 9. DAS Flow 3. MFC Flow 2.8 Flow Standard 3. NOTES: Pump diaphragm replaced, filter replaced, elbow cleaned. No calibration was necessary. Difference

OZONE ANALYZER VERIFICATION & CALIBRATION () ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS Logger Slope Correction.9966 Logger Intercept Correction.848 CALIBRATION ACCEPTANCE CRITERIA (<=) TRANSFER STANDARD AMBIENT ANALYZER STATION REFERENCE Mean Absolute Difference (%) 3% Thermo Thermo Thermo Maximum Absolute Difference (%) 3% Linearity % of Fullscale % 49i 49i 49i DATA ACCEPTANCE CRITERIA (<=) 34596 374586 374584 Mean Absolute Difference (%) % Coefficient Coefficient.6 Coefficient. Maximum Absolute Difference (%) % Background Background -.2 Background Linearity % of Fullscale 2% Cell A Intensity (Hz) 53 Cell A Intensity (Hz) 7389 Cell A Intensity (Hz) 8638 SLOPE INT Cell B Intensity (Hz) 8769 Cell B Intensity (Hz) 866 Cell B Intensity (Hz) 92997 Transfer Standard Correction Factors Flow A (lpm).744 Flow A (lpm).78 Flow A (lpm).67 Flow B (lpm).762 Flow B (lpm).697 Flow B (lpm).67 Full Scale (ppb) 25 Pressure (mmhg) 625.3 Pressure (mmhg) 597.7 Pressure (mmhg) 624.6 Linear Regression Plot Bench Temp ( C) 26.8 Bench Temp ( C) 36.4 Bench Temp ( C) 33.2 Bench Lamp Temp ( C) 54.3 Bench Lamp Temp ( C) 53.9 Bench Lamp Temp ( C) 53.9 Ozone Lamp Temp ( C) 68.3 Ozone Lamp Temp ( C) 67. Ozone Lamp Temp ( C) Ozone Source X Ozone Source Transfer Standard Level LEVEL 2 Transfer Standard Level LEVEL 3 O3 LAMP TRANSFER STANDARD AMBIENT ANALYZER STATION REFERENCE POINT TARGET % or mv Display Corrected DAS Diff %Diff Linearity % DAS Diff %Diff Linearity % ZERO -.2.. -. N/A.% -. -.2 N/A.% 225 96 98.9 24.6 5.7 2.9% -.2% 2.6.7.9%.% 2 5 53.7 56. 6. 4. 2.5%.% 57.5.5.9% -.% 3.6 3.2 5.6 2.4 2.3%.% 4.4.2.% -.2% 4 8 69 7.2 72..8 2.5%.% 7.2..%.% 5 6 57.7 58.8 59.8..8%.% 58. -.7 -.2%.2% ZERO -.2..3.2 N/A -.% -.6 -.7 N/A -.% Mean ABS % Diff 2.4% Mean ABS % Diff.8% Max ABS % Difference 2.9% Max ABS % Difference.2% Analog Test Analyzer DAS Reference DAS Slope.28 Slope.5 Line Loss Test Analyzer Display Span (site tubing) 25 Span (bypass tubing) 23 NOTES: Zero Full Scale -.22 249.9.7 25. % P/F.% Y-Intercept -.7 Y-Intercept -.99 Correlation. Correlation. Analyzer DAS (ppb) 5 4 3 2 Residuals Plot Residual (ppb) 5-5 -.987 -.2998 2 3 y =.289x -.367 Transfer Standard (ppb) R² = 5-5 5 5 2 25 Regression Concentration Value (ppb)

OZONE ANALYZER VERIFICATION & CALIBRATION () ABBR. CANY-IS CLIENT NPS FIELD SPECIALIST M. Farinacci DATE /29/26 SITE NAME Island in the Sky DATE OF LAST VISIT 5/4/26 Network type NPS Logger Slope Correction.9964 Logger Intercept Correction.36 CALIBRATION ACCEPTANCE CRITERIA (<=) TRANSFER STANDARD AMBIENT ANALYZER STATION REFERENCE Mean Absolute Difference (%) 3% Thermo Thermo Thermo Maximum Absolute Difference (%) 3% Linearity % of Fullscale % 49i 49i 49i DATA ACCEPTANCE CRITERIA (<=) 34596 374586 374584 Mean Absolute Difference (%) % Coefficient Coefficient.8 Coefficient. Maximum Absolute Difference (%) % Background Background -.2 Background Linearity % of Fullscale 2% Cell A Intensity (Hz) 98593 Cell A Intensity (Hz) 7375 Cell A Intensity (Hz) 8622 Cell B Intensity (Hz) 858 Cell B Intensity (Hz) 7988 Cell B Intensity (Hz) 92839 Transfer Standard Correction Factors.987 Flow A (lpm).733 Flow A (lpm).77 Flow A (lpm).674 Flow B (lpm).763 Flow B (lpm).697 Flow B (lpm).669 Full Scale (ppb) 25 Pressure (mmhg) 625.6 Pressure (mmhg) 598.6 Pressure (mmhg) 625.2 Linear Regression Plot Bench Temp ( C) 33.4 Bench Temp ( C) 34.7 Bench Temp ( C) 35 Bench Lamp Temp ( C) 54.3 Bench Lamp Temp ( C) 53.7 Bench Lamp Temp ( C) 53.9 Ozone Lamp Temp ( C) 68.5 Ozone Lamp Temp ( C) 67.3 Ozone Lamp Temp ( C) Ozone Source X Ozone Source Transfer Standard Level LEVEL 2 Transfer Standard Level LEVEL 3 POINT TARGET O3 LAMP TRANSFER STANDARD AMBIENT ANALYZER STATION REFERENCE % or mv Display Corrected DAS Diff %Diff Linearity % DAS Diff %Diff Linearity % ZERO -..2.2 -. N/A.% -. -.3 N/A.% 2 99.9 22.8 23.9..5%.% 24..2.6%.% 2 5 55.8 58.2 59.4.2.8% -.% 58.9.7.5%.% 3 2.7 4.4 5..6.6%.% 4.6.2.2%.% 4 8 69.4 7.6 7..4.6%.% 7.7..%.% 5 6 57.7 58.8 59.3.5.9%.% 59..4.6% -.% ZERO -.3..8.8 N/A -.2% -.4 -.4 N/A.% Mean ABS % Diff.7% Mean ABS % Diff.4% Max ABS % Difference.9% Max ABS % Difference.6% Analog Test Analyzer DAS Reference DAS Slope.4 Slope.7 Zero.7 Full Scale 25.7 25 Y-Intercept.3 Y-Intercept -.3 Correlation. Correlation. 5 4 3 2 Residuals Plot Residual (ppb) Analyzer DAS (ppb) 5-5 - SLOPE INT -.2998 2 3 y =.26x -.6234 Transfer Standard (ppb) R² = 5-5 5 5 2 25 Regression Concentration Value (ppb) NOTES:

CALIBRATION AND VERIFICATION STANDARDS ABBR. CANY-IS SITE NAME Network type CLIENT NPS Island in the Sky NPS FIELD SPECIALIST M. Farinacci DATE DATE OF LAST VISIT /29/26 5/4/26 MANUFACTURER MODEL SERIAL # Calibration Expiration Date Ozone Transfer Standard Thermo 49i 34596 /28/27 MFC High Flow Reference BIOS Definer 22-H 2694 2/8/27 MFC Low Flow Reference Temperature Reference Eutechnics 44 38286 9/8/27 AT/RH Sensor Reference Vaisala HMP55 G2837 4/5/27 Barometric Pressure Reference Wind Speed Reference (high rpm) RM Young 882 CA 3628 4/8/27 Wind Speed Reference (low rpm) Wind Speed Torque Gauge RM Young 83 n/a Wind Direction Alignment Reference Brunton Transit 584258 Wind Direction Linearity Reference Wilson Machining 8 pt jig 85 Wind Direction Torque Gauge RM Young 83 n/a Solar Radiation Reference Multiplier 2. Licor Pyranometer PY 83379 /5/27 UV Radiation Reference Multiplier Precipitation Reference Volume 94 ml Texas Electronics FC-525 n/a Voltage Measurement Reference Voltage Source PM Flow Standard # PM Flow Standard #2 PM Flow Standard #3 PM Flow Standard #4 PM Temperature Standard # PM Temperature Standard #2 PM Temperature Standard #3 PM Temperature Standard #4 PM Barometric Pressure Standard # PM Barometric Pressure Standard #2 PM Barometric Pressure Standard #3 PM Barometric Pressure Standard #4 TEOM MTV Standard HiVol Direct Flow Standard HiVol Orifice Plate Orifice Manometer Stagnation Manometer

Calibration Certificate CertificateNo. 77674 Sold To: Air Resource Specialists, Inc. Product 2-22H Definer 22 High Flow 9 Sharp Point Drive Serial No. 2694 Fort Collins, CO 8525 Cal. Date 8-Feb-26 US All calibrations are performed at Mesa Laboratories, Inc., Park Place, Butler, NJ, 745, an ISO 725:25 accredited laboratory through NVLAP of NIST. This report shall not be reproduced except in full without the written approval of the laboratory. Results only relate to the items calibrated. This report must not be used to claim product certification, approval, or endorsement by NVLAP, NIST, or any agency of the Federal Government. As Received Calibration Data Lab. Pressure 757 mmhg Technician Lilianna Malinowska Lab. Temperature 22.2 C Instrument Reading Lab Standard Reading Deviation Allowable Deviation As Received sccm 26446.52 sccm -.%.% Out of Tolerance sccm 536.67 sccm -.%.% Out of Tolerance sccm 624.89 sccm -.%.% Out of Tolerance 2.4 C 2.4 C - ±.8 C In Tolerance 757 mmhg 757 mmhg - ± 3.5 mmhg In Tolerance Mesa Laboratories Standards Used Description Standard Calibration Date Calibration Due Date ML-8-44 897 29-Nov-25 28-Nov-26 Percision Thermometer 3546 2-Sep-25 2-Sep-26 Precision Barometer 298392 28-Jun-25 27-Jun-26 Mesa Laboratories Inc. Park Place Butler, NJ 745 USA (973) 492-84 FAX (973) 492-827 www.mesalabs.com Symbol MLAB on the NAS of 2 CAL2-48 Rev G5

As Shipped Calibration Data Certificate No 77674 Lab. Pressure 766 mmhg Technician Lilianna Malinowska Lab. Temperature 22.2 C Instrument Reading Lab Standard Reading Deviation Allowable Deviation As Shipped 25322 sccm 2523.5sccm.79%.% In Tolerance 528.6 sccm 5.8 sccm.54%.% In Tolerance 5.3 sccm 5.65 sccm.58%.% In Tolerance 22.2 C 22.2 C - ±.8 C In Tolerance 766 mmhg 766 mmhg - ± 3.5 mmhg In Tolerance Mesa Laboratories Standards Used Description Standard Calibration Date Calibration Due Date ML-8-44 897 29-Nov-25 28-Nov-26 Percision Thermometer 3546 2-Sep-25 2-Sep-26 Precision Barometer 298392 28-Jun-25 27-Jun-26 Calibration Notes The expanded uncertainty of flow, temperature, and pressure measurements all have a coverage factor of k = 2 for a confidence interval of approximately 95%. Flow testing is in accordance with our test number PR8-3 with an expanded uncertainty of.8% using high-purity nitrogen or filtered laboratory air. Flow readings in sccm are performed at STP of 2. C and 76 mmhg. Pressure testing is in accordance with our test number PR8- with an expanded uncertainty of.6 mmhg. Temperature testing is in accordance with our test number PR8-2 with an expanded uncertainty of.4 ºC. Traceability to the International System of Units (SI) is verified by accreditation to ISO/IEC 725 by NVLAP under NVLAP Code 266-. Technician Notes: Louis Guido, Chief Metrologist Mesa Laboratories Inc. Park Place Butler, NJ 745 USA (973) 492-84 FAX (973) 492-827 www.mesalabs.com Symbol MLAB on the NAS 2 of 2 CAL2-48 Rev G5