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Material Measurement Laboratory / Chemical Sciences Division

Gas Sensing Metrology Group

Projects/Programs

Displaying 1 - 16 of 16
Photograph of gas cylinders

Audit of EPA Protocol Gas Suppliers

Ongoing
Protocol gas standards are employed in measurements made for compliance purposes; one of the major uses is for measurements of regulated gaseous species from stationary source emitters, i.e., stack gases. Many of these stationary sources are regulated through the Cap and Trade program; therefore
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Bringing the SI to Global Atmospheric Greenhouse Gas Measurement

Ongoing
This multifaceted program leverages expertise in three complementary technical focus areas- all of which involve SI-traceable measurements of relevant atmospheric species such as carbon dioxide, methane, water vapor and oxygen. The efforts include gravimetrically based preparation of primary
Image showing a variety of gas tanks with carbon dioxide

Carbon Dioxide Measurements and Reference Materials

Ongoing
CO 2 Reference Materials The Gas Sensing Metrology Group at NIST has a long history of providing reference materials to industry, monitoring communities, and academia. The program began in the 1970’s by developing an initial suite of CO2 primary standard mixtures (PSMs) to support the US Department
Wordcloud consisting of words CCQM metrology group task etc.

CCQM Activities in the Gas Analysis Working Group

Ongoing
The results from these Key comparisons will be used to benchmark the appropriate Calibration and Measurement Claims (CMCs) of the participating NMIs. CMCs are basically the declared capabilities that an NMI offers to customers, and they are included in a searchable database at the BIPM web site
Illustration of satellite sensing of sunlight reflected by buildings, roads, water and trees to assess radiative warming of the earth.

Climate Science

Ongoing
This program encompasses multifaceted efforts to advance the metrology of climate science. Projects include: development of ultra-high accuracy optical standards and technologies to determine greenhouse gases (GHGs) concentrations, atmospheric lifetimes, and aerosol radiative forcing development of
Photograph of SRM SRM 1694a sulfur dioxide in nitrogen showing a labeled gas cylinder.

Gas Concentration Standards Supporting Atmospheric Monitoring

Ongoing
NIST develops suites of SI-traceable, amount-of-substance, primary gas standard mixtures (PSMs) for key trace and greenhouse gas species to provide traceability to the International System of Units for a range of user communities. Standard Reference Materials (SRMs), certified to the PSMs, are
Map of the world, with six colors used to identify the six regional metrology organizations.

International Comparisons for Chemical Measurements

Ongoing
International agreements and decisions concerning trade and our social well-being increasingly require mutual recognition of measurements and tests among nations. The Mutual Recognition Arrangement (MRA) on national measurement standards and calibration and measurement certificates issued by NMIs
Photograph of an automobile at an emissions testing station, with testing equipment and probe positioned at the car tailpipe.

New Gas Standard Reference Materials to Support the Automotive Industry

Completed
NIST currently supports AIGER members by maintaining reasonable inventories of required gas SRMs that consist of dilute mixtures of key pollutants such as carbon dioxide, carbon monoxide, hydrocarbons, and nitric oxide. Newer vehicles produce lower levels of these pollutants because their engines
Photograph of the NIST Standard Reference Photometer showing the component modules consisting of optical bench with sample and reference tubes, ozone generator module with controls and tubing, and control module with numeric LED displays.

The NIST Standard Reference Photometer for Ozone Measurement Traceability

Ongoing
The concentration of ozone in the atmosphere continues to be an important global issue both scientifically and politically. Stratospheric ozone protects the Earth from harmful UV radiation, while tropospheric ozoneis a major health concern and contributes to global climate change as a greenhouse gas
Photograph of hundreds of gas cylinders in a gas storage facility.

NIST Traceable Reference Material Program for Gas Standards

Ongoing
The Gas Mixture SRM, NTRM, and EPA Protocol Programs provide a mechanism to produce needed calibration gas standards with a well-defined traceability. These mixtures are specified in the Code of Federal Regulations (CFR) to calibrate instruments to be used to monitor regulated emissions. The NTRM

Standards Development to Ensure Reliable Breath Analysis in the Field

Ongoing
Numerous volatile organic compounds (VOCs) have been identified in human breath. These compounds can be produced by the body or by organisms in the body (e.g., bacteria or viruses) and provide a non-invasive window into human health. Inexpensive point-of-care devices are being developed to diagnose
Photography of gas cylinder storage facility with cylinders stored horizontally in movable cabinets.

Traceable Calibration Gases: SRMs, NTRMs, and Protocol Gases

Ongoing
The Gas Sensing Metrology Group prepares the highest level gas standards, known as Primary Standard Gas Mixtures based on precise gravimetric methods and accurate purity analysis. These Primary Standards are verified at NIST, stability confirmed through reanalysis over many years, and compared