Instrumentation Information

Ozone •  PM2.5 •  PM2.5 Speciation •  Carbon Monoxide • Nitrogen DioxideSulfur Dioxide • Carbonyl and VOC •  PAH • BTEX 

Ozone

Ozone analyzer Advanced Pollution Instruments (API) Model 400E Ultraviolet Absorption Ozone analyzer: The State of Vermont AQCD operates two continuous ozone monitoring sites within the state. The instrument samples local ambient air quality 24 hours a day, 365 days a year. Averaging intervals of 1, 5, 60, 480 minutes are automatically logged with the data acquisition systems. The unit is setup and operated to monitor ambient ozone concentrations up to 500 parts per billion. Reference/Equivalent Method Designation: The Model 400 is designated by EPA as a automated Equivalent Method (EQOA-0992-087) for the measurement of ambient concentrations of ozone. The Model 400 must be and is set up and operated as per the reference designation. Principle Utilized: The instrumental operation utilizes the principle of "Ultraviolet Absorption" that is based on the fact that ozone molecules absorb ultraviolet energy at a known wave length of 254nm. The UV light available for detection is proportional to the amount of ozone in the sample chamber.


Fine Particulates (PM2.5)

Sequential SamplerPartisol 2025i Sequential Sampler: Vermont AQCD has 2025i in monitoring sites Burlington, Zampieri and Underhill,  the 2025i samples local ambient air quality every third day for a period of 24 hours. This sampler we operate uses the US EPA VSCC inlet based reference system PM2.5 method. Air is sample at a rate of 1 m3/ hour and the particulate matter is collected on a Teflon filter that is weighed both before and after sampling. 

 

 

 

 

 

Dynamic Measurement SystemR&P TEOM Series 8500 with Filter Dynamic Measurement System (FDMS) : The State of Vermont AQCD operates three FDMS TEOMs in Burlington, Underhill and Bennington, VT. The instrument samples local ambient air quality 24 hours a day, 365 days a year. The FDMS TEOM operates at 30°C and continuously measures PM2.5 mass.

 

 

 

 

API T640Teledyne Advanced Pollution Instrumentation Model T640 PM Mass Monitor Automatic Equivalent Method: EQPM–0516–236

‘‘Teledyne Advanced Pollution Instrumentation Model T640 PM mass monitor,’’ continuous ambient particulate monitor operated at a volumetric flow rate of 5.0 Lpm, equipped with a TAPI 5-Lpm sample inlet (P/N: 081050000), TAPI aerosol sample conditioner (P/N: 081040000), configured for operation with firmware version 1.0.2.126 or later, and operated in accordance with the Teledyne Model T640 Operations Manual. This designation applies to PM2.5 measurements only.

 

 

 

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Fine particulate (PM2.5) Speciation

SASS SamplerMetOne SASS Sampler: The MetOne SASS unit, which measures PM2.5 mass and PM2.5 chemical speciation, is located in Burlington, VT at the Zampieri State Office Building and is part of the EPA Speciation Trends Network (STN). The MetOne SASS was deployed on 12/14/00 on a 1-in-6 day sampling schedule. Sampling frequency was increased to 1-in-3 day sampling on 3/2/01. Data is validated on a monthly basis when reports are received from the contract laboratory (Research Triangle Institute). 

 

 

 

IMPROVE SamplerIMPROVE Sampler: The IMPROVE (Interagency Monitoring of Protected Visual Environments) sampler, which measures PM2.5 mass, PM10 mass and PM2.5 chemical speciation, was deployed on 2/15/01 on a 1-in-3 day sampling schedule in Underhill, VT at the Proctor Maple Research Facility. Data is validated at the Crocker Nuclear Laboratory at UC-Davis and is then reported to the operating site usually within a 6-month period. 

 

 

 

URG SamplerURG-3000N Sequential Particulate Speciation Sampler: The State of Vermont AQCD operates the URG sampler at the monitoring site in Burlington at the Zampieri State Office Building. Samples are collected for 24-hours (midnight to midnight) following EPA's 3 day sampling schedule. The URG consists of one module C, one controller, one stand, one stand rain shield and one 36" inlet tube. The controller contains a timer, keypad, and other electronic equipment. The stand contains the vacuum pump & mass flow controller to provide active volumetric flow control; corrections are made for temperature & barometric pressure variations. The sampler controller is used to control the sample collection & acquired data during the sampling. The ambient air enters through an inlet to then pass through a cyclone that removes particulates larger then 2.5 um. The cyclone is located inside the module. The module C collects PM2.5 particulates on a quartz filter. These filters are analyzed for organic & elemental carbon using thermal optical analysis method. (TOA) 

 

 

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Carbon Monoxide (CO)

CO AnalyzerAdvanced Pollution Instruments (API) Model T300 Gas Filter Correlation Carbon Monoxide Analyzer: The State of Vermont AQCD operates two continuous carbon monoxide monitoring sites within the state. The carbon monoxide instrument samples local ambient air quality 24 hours a day, 365 days a year. Carbon monoxide averaging intervals of 1, 5, 60, 480 minutes are automatically logged with the data acquisition systems. The unit is setup and operated to monitor ambient concentrations up to 50 parts per million.  Reference/Equivalent Method Designation: The Model T300 is designated by EPA as a Reference Method (RFCA-0981-054) for the measurement of ambient concentrations of carbon monoxide. The Model T300 must be and is set up and operated as per the reference designation. Principle Utilized The instrumental operation utilizes the principle of "Gas Filter Correlation" that is based on the fact that carbon monoxide molecules absorb infrared radiation at a know spectral wavelength of 4.6 mm. The infrared absorption characteristic is a non-linear technique. The API Model T300 electronics package transforms the data output to a linear format. The signal is then processed to digital and analog outputs.

Carbon Monoxide (CO Trace Level)

CO AnalyzerEcoTech EC9830 TL Analyzer: The State of Vermont AQCD operates two continuous carbon monoxide monitoring sites within the state. The trace level instrument is located at our Underhill site. The carbon monoxide instrument samples local ambient air quality 24 hours a day, 365 days a year. Carbon monoxide averaging intervals of 1, 5, 60, 480 minutes are automatically logged with the data acquisition systems. The unit is setup and operated to monitor ambient concentrations up to 0-5.0 parts per million. Reference/Equivalent Method Designation: The Model EC9830 is designated by EPA must be and is set up and operated as per the reference designation as a Reference Method RFCA-0992-088 for the measurement of ambient concentrations of carbon monoxide. Principle Utilized The instrumental operation utilizes the principle of nondispersive infrared photometer that accurately and reliably measures low concentrations of CO, using gas filter correlation and state-of-the-art optical and electronic technology. The EC9830 analyzer generates infrared radiation (IR) that is absorbed by the CO within the 5-meter folded pathlength. The gas filter correlation wheel facilitates rejection of interferents and the narrow band-pass filter ensures measuring only the CO-sensitive IR wavelengths. The CO content of the sample is continuously measured from a user-supplied air stream of which the instrument extracts 1 slpm (standard liter per minute) of sample. 

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Nitrogen Dioxide (NO2)

NOX AnaylzerAdvanced Pollution Instruments (API) Model T200 Chemiluminescence Oxides of Nitrogen Analyzer: The State of Vermont AQCD operates two continuous oxides of nitrogen monitoring sites within the state. The instrument samples local ambient air quality 24 hours a day, 365 days a year. Averaging intervals of 1, 5, 60, 480 minutes are automatically logged with the data acquisition systems. The unit is setup and operated to monitor ambient NO and NO2 concentrations up to 500 parts per billion. Reference/Equivalent Method Designation: The Model T200 is designated by EPA as a automated Reference Method (RFNA-1289-074) for the measurement of ambient concentrations of nitric oxide. The Model T200 must be and is set up and operated as per the reference designation. Principle Utilized: The instrumental operation utilizes the principle of "Chemiluminescence" that is based on the rapid gas phase reaction of nitric oxide molecules and ozone molecules. Light emissions from the excited nitrogen dioxide molecule to it's lower ground state by a photomultiplier tube (PMT). The API Model T200 electronics package transforms the data output to a linear format.

Nitrogen Oxide (NOy)

NOy analyzerEcoTech 9843 Total Reactive Nitrogen analyzer: The State of Vermont AQCD operates two continuous oxides of nitrogen monitoring sites within the state. The trace level instrument is located at our Underhill site. The instrument samples local ambient air quality 24 hours a day, 365 days a year. Averaging intervals of 1, 5, 60, 480 minutes are automatically logged with the data acquisition systems. Reference/Equivalent Method Designation: This method is utilized to comply with 40 CFR Part 58 Appendix C requiring Ncore monitoring. Principle Utilized: The EC9843 NOy analyzer combines microprocessor control with chemiluminescence detection to provide accurate measurements of NO and NOy in the range of 0-50 ppb with a detection limit of 0.5 ppb.

 

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Sulfur Dioxide (SO2)

SO2 analyzerAdvanced Pollution Instruments (API) Model T100 UV Fluorescence SO2 Analyzer:The State of Vermont AQCD operates two continuous sulfur dioxide monitoring sites within the state. The instrument samples local ambient air quality 24 hours a day, 365 days a year. Averaging intervals of 1, 5, 60, 480 minutes are automatically logged with the data acquisition systems. The unit is setup and operated to monitor ambient concentrations up to 500 parts per billion. The one hour and running three and twenty four hour averages from the two monitoring sites are compiled and presented on a hourly basis on this web site. Reference/Equivalent Method Designation The Model T100 is designated by EPA as a automated Equivalent Method (EQSA-0486-060) for the measurement of ambient concentrations of sulfur dioxide. The Model T100 must be and is set up and operated as per the equivalency designation. Principle Utilized: The instrumental operation utilizes the principle of "Pulsed Fluorescence" that is based on the fact that sulfur dioxide molecules absorb fluorescent energy, producing electronically excited SO2 molecule with a known spectral decay rate to the ground state. The fluorescence emitted by the reaction is detected by a photo multiplier tube and the signal is converter proportionally to a electronic output signal. 

 

 

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Combined Carbonyl & VOC

Carbonyl and VOC SamplerATEC Model 2200 Combined Cartridge/ Canister Sampler: The State of Vermont AQCD operates sampling for these methods in Burlington, RUtland and Underhill. Carbonyl compound sampling and analysis is performed following EPA method TO11A from EPA's Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air EPA/625/R-96/010b. Carbonyl samples are collected using Waters Sep-Pak DNPH-silica cartridges (2,4-Dinitrophenylhydrazine) and an ATEC Model 2200 Cartridge/ VOC sampler. Carbonyl samples are collected over 24-hour periods (midnight to midnight) . DNPH cartridges are transported at 4°C to the laboratory for analysis. 

The Vermont Agriculture & Environmental Lab performs the Carbonyl cartridge sample extraction and subsequent analysis for 14 compounds using a Waters High Performance Liquid Chromatograph (HPLC) with a multi-wavelength UV detector. VOC sampling and analysis is performed following EPA method TO15 from EPA's Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air EPA/625/R-96/010b. VOC samples are collected in specially treated 6-liter Silcosteel stainless steel canisters (which have been pre-cleaned and certified prior to each use) using ATEC Model 2200 Cartridge/Canister Sampler. VOC samples are collected over 24-hour periods (midnight to midnight). Canister samples are transported to the laboratory for analysis. 

The Vermont DEC performs the VOC canister sample analysis for 59 compounds using an ENTECH model 7100 Cryogenic Concentrator Microscale Purge and Trap Unit (to acquire and condition the sample) and a Hewlett-Packard (HP) 6890 gas chromatograph/5973 mass spectrometer (GC/MS) with the mass selective detector.

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PAH (Semi Volatile)

PAH SamplerPAH (semi-volatile) TISCH PUF+: The State of Vermont AQCD operates the PUF at the monitoring site in Underhill . Samples are collected for 24-hours (midnight to midnight) following EPA's 6 th day sampling schedule. Poly-aromatic hydrocarbon (PAH) sampling and analysis is performed following EPA method TO-13A from EPA's Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air EPA/625/R-96/010b and the ASTM D6209-98. The TISCH PUF+ sampler is used to collect ambient air samples for determining vapor and particulate concentrations of PAHs (semi-volatile organic compounds such as naphthalene and benzo [a] pyrene). This sampler is comprised of a small outdoor aluminum shelter which houses a vacuum/blower motor and a programmable microprocessor timer/controller which automatically starts and stops sample collection, controls air flow through the sampling module and collects and stores sample-related information. Approximately 200m 3 of air is sampled through a special module containing a polyurethane foam (PUF) plug insert combined with a special adsorbent (XAD-2: styrene-divinylbenzene resin) and a 104 mm quartz-fiber filter. Samples are kept cool during transport/shipment to the laboratory for analysis. The EPA contract lab performs the PAH/semi-volatile analysis for 22 compounds using a Soxhlet extraction and gas chromatography/mass spectrometry (GS/MS).

 

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BTEX  (Gas Chromatograph)

Gas ChromatographSyntech Spectras GC955 series 600 Gas Chromatograph: The State of Vermont AQCD operates a semi-continuous BTEX (benzene, toluene, ethylbenzene, xylene) monitoring site in Burlington . The BTEX instrument samples local ambient air quality 24 hours a day, 365 days a year. BTEX 15 minute averaging intervals are automatically written to a log file on the instrument. The unit is setup and operated to monitor ambient concentrations up to 5 parts per billion. Principle Utilized The instrumental operation utilizes the principle of "Gas Chromatography" with a "Photoionization Detector" (GC/PID). During each 15-minute cycle, the sampling cylinder/piston draws a total of 150 cc of ambient air sample through a preconcentrator at set intervals. Simultaneously, the previous 15 minute sample undergoes a 15 minute analysis cycle. The sample is thermally desorbed from the preconcentrator into a stripper column and then into the analysis column. Once BTEX compounds move through the stripper column (after injection mode) the 10-port valve switches and back flushes the remaining VOCs from the stripper column. The BTEX compounds are separated in the column and exit to the PID for measurement at specific retention times. The PID ionizes the molecules using ultraviolet radiation. The charged gas ions flow to charged electrodes in the sensor and produce a current which is measured and displayed as a concentration on the meter. The greater the concentration of the component, the more ions are produced, and the greater the current. 

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