Page 162 - Praxair - Specialty Gases and Equipment Solutions

Environmental

Assuring Compliance

NIST Traceable Reference Materials (NTRMs) EPA Protocols
NIST Traceable Reference Materials (NTRM) – Certified by EPA Protocol gas mixtures are required for the monitoring
the National Institute of Standards and Technology (NIST) of emissions from stationary sources and are used for the
and accepted by the Environmental Protection Agency calibration and Relative Accuracy Test Audit (RATA) of
(EPA), as the highest accuracy standards commercially Continuous Emission Monitors (CEMs) as specified under
produced. These standards are the regulatory equivalent EPA 600/R-12/531.
to NIST’s Standard Reference Materials (SRMs) and are Praxair EPA Protocols are NIST traceable with a ± 1%
made up of the same components and are within the accuracy, produced in accordance with the latest EPA
same analytical range. specifications. The benefits to you include:
The NIST Traceable Reference Materials (NTRM) program, ■ Certified analytical uncertainty of ±1% is possible for
was developed in a consortium with NIST, EPA, and reliable analyzer certification, calibration and audit.
industry participation. The program was intended to ■ Multiple production facilities and stocking locations
increase the availability of NIST traceable primary gas to help ensure an uninterrupted supply of Protocol
standards to industry. NTRMs supplement the supply of standards.
existing gaseous Standard Reference Materials (SRMs)
and can be used wherever SRMs have been used in the ■ Standards that are labeled and supplied with complete
past. These mixtures are similar in composition to NIST documentation required to help ensure compliance.
primary and SRM standards. However, because the ■ Praxair’s cylinder treatment process is designed to
concentration of the certified component can be bracketed provide maximum allowed shelf life within the stated
by existing primary NIST standards, NTRM component analytical uncertainty. (Please see page D•162 for
concentrations can fall above, below or between exist- certification periods).
ing SRM concentrations. This offers end users additional ■ Praxair maintains a complete range of NIST Standard
calibration reference points for greater accuracy and lower Reference Materials (SRMs) and NIST Traceable
uncertainty measurements. Reference Materials (NTRMs).
NTRMs are manufactured in a batch by Praxair, with
NIST assigning the component concentration. The
NTRM program was designed to replace the EPA’s
Certified Reference Material (CRM) program. EPA has
stated that it accepts NTRMs in place of CRMs and
allows their use as equivalent to SRMs for certification Environmental
of emissions and production of mixture standards, such
as EPA Protocols.
Available mixture components include:
■ Carbon Dioxide
■ Carbon Monoxide
■ Hydrogen Sulfide
■ Methane
■ Nitric Oxide
■ Nitrogen Dioxide
■ Oxygen
■ Propane
■ Sulfur Dioxide
Concentration ranges fall closely above, below or between
existing NIST SRM concentrations.
To address any application questions you have, technical
support is available from your Praxair Sales Representative
or North America Technical Support Center:
1-877-PRAXAIR

1-877-PRAXAIR www.praxairdirect.com D•161