When you need to perform critical water testing, look to us for an extensive selection of electrochemical meters, controllers, probes, electrodes, test kits, buffers, and standards. Our field and laboratory instrumentation include water analysis instruments for dissolved oxygen, temperature, pH, conductivity, salinity, and turbidity.
Environmental Express offers a full line of products for pH, Electrochemistry, and Water Quality testing. Oakton® is now part of the Environmental Express brand in the Cole-Parmer family of products. Oakton provides incredible quality at budget-friendly prices. Whether you are performing water analysis in the lab or field, we have the meter or tester for you. The Oakton line includes handheld portable meters, pocket testers, benchtop meters, and specialty pH/mV meters plus ISE electrodes and ISFET electrodes that handle specific ion applications and harsh environments.
We also carry Thermo Orion, YSI, Lamotte, and other brands to meet all of our customers' needs.
If you don't see the product you need, please reach out to our Tech Support Team and they will be happy to assist you. Please contact us at 800-745-8218 or email [email protected].
Benchtop Meters and Kits
pH Benchtop Meters
pH meters measure the water quality parameters critical to many laboratory, industrial, chemical, and processing applications. Whether you are performing water analysis in the lab or field, we have the pH meter to meet your needs.
Conductivity Benchtop Meters
Conductivity, resistivity, and TDS (total dissolved solids) meters are available for a variety of environments and applications. When you need to measure conductivity in the field, our pocket conductivity testers and portable conductivity meters may be the right choice for you. Many models have an onboard memory to store and recall conductivity readings taken. If the laboratory is your base, select from benchtop conductivity meters. Conductivity meters can include a USB or RS-232 computer interface.
Ion Selective Benchtop Meters
Ion selective meters measure the water quality parameters critical to many laboratory, industrial, chemical, and processing applications. Whether you are performing water analysis in the lab or field, we have the ISE meter to meet your needs. Pocket-sized testers are an economical alternative for routine measurements. Handheld portable meters are ideal for field, manufacturing floor, and lab. Benchtop meters are the choice for high-accuracy measurements on the lab bench. Specialty pH/mV meters plus ISE electrodes and ISFET electrodes handle specific ion applications or harsh environments.
Dissolved Oxygen Benchtop Meters
Dissolved oxygen meters (DO) are available in handheld and benchtop models. When selecting a dissolved oxygen meter, keep in mind the following variables: types of probes, waterproof housing, automatic barometric pressure compensation, manual barometric pressure compensation, salinity adjustment, temperature compensation, memory capabilities, and replaceable membranes, caps and modules.
Turbidity Benchtop Meters
We offer a range of turbidity meters to meet your regulatory standards: US EPA Method 180.1, ISO 7027, and ASTM 6855-03. Select your turbidity meter based on the measurement requirements. Handheld, portable turbidity meters are good for the laboratory, manufacturing floor, and field use. Benchtop turbidity meters are ideal for lab applications typically offering larger displays and more robust data management systems.
Multiparameter Benchtop Meters
Multiparameter water testing meters are key tools for electrochemistry measurements. Many environmental, laboratory, and research scientists rely on these water quality meters to take accurate and efficient measurements of many different substances simultaneously. The parameters most commonly measured include pH, conductivity, dissolved oxygen (DO), temperature, ORP, TDS, turbidity, barometric pressure and salinity.
Benchtop Meter Parts/Accessories
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Portable Meters and Kits
pH Portable Meters
pH meters measure the water quality parameters critical to many laboratory, industrial, chemical, and processing applications. Whether you are performing water analysis in the lab or field, we have the pH meter to meet your needs. Handheld portable meters are ideal for field, manufacturing floor, and lab.
Conductivity Portable Meters
Conductivity, resistivity, and TDS (total dissolved solids) meters are available for a variety of environments and applications. When you need to measure conductivity in the field, our pocket conductivity testers and portable conductivity meters may be the right choice for you. Many models have an onboard memory to store and recall conductivity readings taken. If the laboratory is your base, select from benchtop conductivity meters. Conductivity meters can include a USB or RS-232 computer interface.
Ion Selective Portable Meters
Ion selective meters measure the water quality parameters critical to many laboratory, industrial, chemical, and processing applications. Whether you are performing water analysis in the lab or field, we have the ISE meter to meet your needs. Pocket-sized testers are an economical alternative for routine measurements. Handheld portable meters are ideal for field, manufacturing floor, and lab. Benchtop meters are the choice for high-accuracy measurements on the lab bench. Specialty pH/mV meters plus ISE electrodes and ISFET electrodes handle specific ion applications or harsh environments.
Dissolved Oxygen Portable Meters
Dissolved oxygen meters (DO) are available in handheld and benchtop models. When selecting a dissolved oxygen meter, keep in mind the following variables: types of probes, waterproof housing, automatic barometric pressure compensation, manual barometric pressure compensation, salinity adjustment, temperature compensation, memory capabilities, and replaceable membranes, caps and modules.
Turbidity Portable Meters
We offer a range of turbidity meters to meet your regulatory standards: US EPA Method 180.1, ISO 7027, and ASTM 6855-03. Select your turbidity meter based on the measurement requirements. Handheld, portable turbidity meters are good for the laboratory, manufacturing floor, and field use. Benchtop turbidity meters are ideal for lab applications typically offering larger displays and more robust data management systems.
Multiparameter Portable Meters
Multiparameter water testing meters are key tools for electrochemistry measurements. Many environmental, laboratory, and research scientists rely on these water quality meters to take accurate and efficient measurements of many different substances simultaneously. The parameters most commonly measured include pH, conductivity, dissolved oxygen (DO), temperature, ORP, TDS, turbidity, barometric pressure and salinity.
Portable Meter Parts/Accessories
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Pocket Testers
pH Pocket Testers
pH meters and ion meters measure the water quality parameters critical to many laboratory, industrial, chemical, and processing applications. Whether you are performing water analysis in the lab or field, we have the pH meter to meet your needs. Pocket-sized testers are an economical alternative for routine measurements. Handheld portable meters are ideal for field, manufacturing floor, and lab. Benchtop meters are the choice for high-accuracy pH measurements on the lab bench. Specialty pH/mV meters plus ISE electrodes and ISFET electrodes handle specific ion applications or harsh environments.
Conductivity Pocket Testers
Conductivity, resistivity, and TDS (total dissolved solids) meters are available for a variety of environments and applications. When you need to measure conductivity in the field, our pocket conductivity testers and portable conductivity meters may be the right choice for you. Many models have an onboard memory to store and recall conductivity readings taken. If the laboratory is your base, select from benchtop conductivity meters. Conductivity meters can include a USB or RS-232 computer interface.
ORP Pocket Testers
ORP meters are ideal for checking sanitizing solutions, chromate reduction, cyanide oxidation, and other ORP readings.
The pocket-sized Oakton ORPTestr® 5 has a replaceable single-junction sensor which can be easily switched out, allowing you to save money by using the tester body over and over again. A large LCD makes viewing measurements easy and features a three-color backlight indicating operational mode-blue for measurement, green for calibration and red for alarm condition. It is ideal for checking dirty water, heavy metals, sulfides, and organic materials.
The Oakton ORPTestr® 50 features a replaceable double-junction platinum electrode. Valox® electrode body resists most chemicals. Use these versatile instruments for applications ranging from swimming pool testing to pulp bleaching. Meter features 2 mV accuracy and a ±200 mV offset. Housing allows you to attach a lanyard (included) for easy retrieval. Additional features include a hold function, auto-off function, self-diagnostic error messages, and a three-segment battery-life indicator.
Multiparameter Pocket Testers
Multiparameter water testing meters are key tools for electrochemistry measurements. Many environmental, laboratory, and research scientists rely on these water quality meters to take accurate and efficient measurements of many different substances simultaneously. The parameters most commonly measured include pH, conductivity, dissolved oxygen (DO), temperature, ORP, TDS, turbidity, barometric pressure and salinity.
Pocket Tester Parts/Accessories
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Probes and Electrodes
pH Probes and Electrodes
We offer a wide variety of pH probes and electrodes for your specific application including general and field-rugged electrodes.
Conductivity Probes
Conductivity electrodes work with conductivity meters to measure the electrical conductivity in a solution. The conductivity cell surface is usually platinum, titanium, gold-plated nickel, or graphite. When choosing conductivity cells keep in mind the cell constant, body material, electrode material, ATC element, fitting, cell type, and temperature range.
Ion Selective Electrodes
Ion-selective electrodes (ISE) are pH laboratory electrodes that determine the concentration of specific ions. Choose from cost-effective ion-selective electrodes and solutions to combination ion-selective electrodes featuring both half-cell and reference cell in one electrode. To get the most out of your electrodes, rinse between samples with distilled or deionized water and gently blot with a lab wipe. Never wipe. Do not store electrodes in distilled or deionized water.
Dissolved Oxygen Probes
Our DO/BOD probes and accessories are compatible with dissolved oxygen transmitters and controllers. Probes are available in a variety of materials including glass and stainless steel. Cables and replacement membrane cartriges are also available. When choosing probes, refer to the following specifications: temperature compensation and range, stability, response time, sterilization temperature, maximum pressure, "H" length, body diameter, and mount.
ORP Probes
Oakton combination electrodes are available in a variety of styles to meet the needs of your application. Epoxy electrodes are impact resistant and provide excellent durability for field applications. Glass electrodes withstand aggressive chemicals. Choose junction and tip style based on the needs of your application. All electrodes feature Ag/AgCl reference cells.
Multiparameter Probes
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Probe Parts/Accessories
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Buffers, Standards and Solutions
pH Buffers
pH buffers or hydrogen ion buffers are buffer solutions that allow you to adjust your testing system to precisely measure your samples' unknown pH. Our selection of pH value buffers and pH solution packs can help you feel more confident about accuracies. For best accuracy make sure you perform standardization with fresh buffer solution. Never pour used buffer back into the bottle. Always discard buffer solution after use. Use buffers that frame the pH range of the samples you are testing; match the temperature of the buffer to the temperature of the samples. Calibrate your system before each use or set of uses. We even have buffer pouches to keep your accuracy when you're on the go!
Oakton pH buffers are compared against, and are traceable to, NIST Standard Reference Materials. Each bottle includes a NIST-traceable calibration report stating accuracy at 25°C to ±0.010 pH. Color-coded and colorless buffers are available in 500-mL, 1-L, or 4-L packaging sizes. Additional values and packaging sizes are available. Store at room temperature.
Certified Reference Materials (CRM) meet federal, state, and or local agencies' strictest mandates, and deliver exact calibration results for any pH meter. A2LA ISO/IEC 17025:2005 (1750.01) (Calibration Laboratory) and ISO 17034 (Certified Reference Material Producer) provide highest achievable levels of product production, documentation, and accuracy. Additional accreditations include ISO 31 (content) and ISO 35 (statistical analysis). ISO 9001 ensures that world-class product standards for Materials are always met.
Traceable® products are calibrated to NIST-traceable standards and ready to use as soon as you receive it. Each product goes through an intense vetting process before it can carry the Traceable name, and it includes NIST-traceable certification. This means that a 17025-accredited calibration test lab has confirmed that the product meets or exceeds all stated specifications, saving you both time and money by not having to calibrate separately. NIST-traceable calibration also helps you meet quality standards and regulatory compliance for ISO, FDA, cGMP, VFC, CAP, CLIA and Joint Commission requirements.
Conductivity Standards
Oakton Conductivity Standards are ideal for laboratory and field analysis.
- All Oakton Conductivity and TDS Standards are traceable to NIST standard reference materials
- Solutions help you calibrate conductivity instruments to ensure accuracy
- Standard values given at 25°C
- KCl, NaCl and 442 conversions printed on the bottle for ease of use (excluded on 60-mL bottle, but included in insert)
- Temperature corrections are printed on the bottle, with certified values listed in tables and referenced to 25°C (excluded on 60-mL bottle, but included in insert)
- Manufactured under ISO 9000 quality guidelines and traceable to NIST standards
- If unopened, shelf life is 1 year. If opened recommended shelf life is 4 months
- Conductivity options range from 1 µS/cm to 200,000 µS/cm
Traceable® conductivity standards are Certified Reference Materials, making one of the most accurate available.
- All Oakton® Traceable® conductivity standards are NIST-traceable reference materials
- Supplied with a calibration report from an ISO 17034 and ISO 17025 accredited laboratory
- These standard solutions let you calibrate conductivity instruments to ensure accuracy
- If unopened, shelf life is one year; once opened, shelf life will vary by solution value
- Oakton® Traceable® conductivity and TDS standards have detailed labels: KCl, NaCl, and 442 conversions, temperature corrections, and certified values referenced to 25°C-convenient!!
- Average accuracy at 25°C is ±0.25 microsiemens for 1, 5, 10 microsiemen (µS) solutions, or ±0.25% for all other solutions. The tested uncertainty is shown on the certificate, whichever is greater
- Conductivity options range from 1 to 200,000 µS/cm
- Batch-tested solutions are lot certified; a few bottles from a single lot are analyzed
- Individually-tested solutions are certified by the bottle-each bottle is analyzed for the best accuracy
METHODS SUPPORTED
Certified reference material meets test requirements for Federal, State, and local agencies, CAP, ASTM, NCCLS, CLSI, ACS, CLIA, AOAC, EPA, APHA, AWWA, WEF, USGS, USP, and ISO. Traceable® Conductivity Standards complies with and is essential for use in these official methods: AOAC 973.40, EPA 120.1, Standard Method 2510 (APHA, AWWA, WEF), ISO 7888, DIN 38404, ASTM D1125, USGS I-1780, USP 645, and for A2LA/NVLAP accreditations/ISO 9000 certifications. Material may be used to calibrate all conductivity meters and to determine all conductivity cell constants.
A2LA ACCREDITATION ISO/IEC 17025:2005 (1750.01)
To assure accuracy an individually serial-numbered Traceable® Certificate is supplied to indicate traceability to standards provided by NIST (National Institute of Standards and Technology) and/or a National Standards Laboratory. A2LA accredited certification provides the highest achievable level of quality assurance, documentation, and accuracy. Conductivity Standards are produced in an A2LA accredited ISO/IEC 17025:2005 (1750.01) calibration laboratory. Additional certifications include ISO 31 (certificate content) and ISO 35 (statistical analysis), plus ISO 9001 (certified quality manufacturer).
Turbidity Standards
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Water quality standards, and solutions are available in a wide variety of buffers, storage solutions, cleaning solutions, and standards including NIST-traceable reference materials; a calibration report from an ISO Guide 34 and ISO 17025 accredited laboratory for the highest accuracy available!
ORP Standards
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Dissolved Oxygen Solutions
Oakton® zero oxygen standard solution ensures accuracy of your dissolved oxygen meter. For accurate dissolved oxygen blanking, the solution undergoes testing using the Winkler method. The special packaging in the PETG bottle improves shelf life. Follow all precautions recommended by your electrode manufacturer to ensure acceptable results.
Electrode Fill/Storage Solutions
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Keep your pH probes clean and properly stored for longevity Remove grease and oil deposits from your electrodes with our cleaning solution. Cleaning solution contains pepsin. After cleaning, keep your electrodes in proper working condition with our storage solution.
Ion Selective Electrode Solutions
Ensure consistent and accurate readings from your ISE with these ionic strength adjustors .
Test Strips
pH and Water Quality Test Strips
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Field Test Kits
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