ASTM D5454-11(2020)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5454 − 11 (Reapproved 2020)
Standard Test Method for
Water Vapor Content of Gaseous Fuels Using Electronic
Moisture Analyzers
This standard is issued under the fixed designation D5454; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope changes the capacity of the capacitor in relation to the water
vapor present. Silicone cells also operate on this principal by
1.1 This test method covers the determination of the water
reporting a capacitance change when adsorbing or desorbing
vapor content of gaseous fuels by the use of electronic moisture
water vapor.
analyzers. Such analyzers commonly use sensing cells based
on phosphorus pentoxide, P O , aluminum oxide, Al O , or
2 5 2 3
3.1.2 electrolytic-type cell—this cell is composed of two
silicon sensors piezoelectric-type cells and laser based tech-
noble metal electrode wires coated with P O . A bias voltage is
2 5
nologies.
applied to the electrodes, and water vapor chemically reacts,
1.2 This standard does not purport to address all of the
generating a current between the electrodes proportional to the
safety concerns, if any, associated with its use. It is the
water vapor present.
responsibility of the user of this standard to establish appro-
3.1.3 piezoelectric-type cell—sensor consists of a pair of
priate safety, health, and environmental practices and deter-
electrodes which support a quartz crystal (QCM) transducer.
mine the applicability of regulatory limitations prior to use.
When voltage is applied to the sensor a very stable oscillation
1.3 This international standard was developed in accor-
occurs. The faces of the sensor are coated with a hygroscopic
dance with internationally recognized principles on standard-
polymer. As the amount of moisture absorbed onto the polymer
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom- varies, a proportional change in the oscillation frequency is
mendations issued by the World Trade Organization Technical produced.
Barriers to Trade (TBT) Committee.
3.1.4 laser-type cell—consists of a sample cell with an
optical head mounted on one end and a mirror mounted on the
2. Referenced Documents
other; however, some models will not need a mirror to reflect
2.1 ASTM Standards:
the light wavelength emitted from the laser. The optical head
D1142 Test Method for Water Vapor Content of Gaseous
contains a NIR laser, which emits light at a wavelength known
Fuels by Measurement of Dew-Point Temperature
to be absorbed by the water molecule. Mounted, the laser is a
D1145 Test Method for Sampling Natural Gas (Withdrawn
detector sensitive to NIR wavelength light. Light from the laser
1986)
passes through the far end and returns to the detector in the
D4178 Practice for Calibrating Moisture Analyzers
optical head. A portion of the emitted light, proportional to the
3. Terminology
water molecules present, is absorbed as the light transits the
sample cell and returns to the detector.
3.1 Definitions of Terms Specific to This Standard:
3.1.1 capacitance-type cell—this cell uses aluminum coated
3.1.5 water content—water content is customarily expressed
with Al O as part of a capacitor. The dielectric Al O film
2 3 2 3 in terms of dewpoint, °F or °C, at atmospheric pressure, or the
nonmetric term of pounds per million standard cubic feet,
1 lb/MMSCF. The latter term will be used in this test method
This test method is under the jurisdiction of ASTM Committee D03 on Gaseous
Fuels and is the direct responsibility of Subcommittee D03.06.04 on Analysis by
because it is the usual readout unit for electronic analyzers.
Colorimetric Techniques. 3
One lb/MMSCF = 21.1 ppm by volume or 16.1 mgm/m of
Current edition approved Jan. 1, 2020. Published January 2020. Originally
ε1
water vapor. Analyzers must cover the range 0.1 to
approved in 1993. Last previous edition approved in 2011 as D5454 – 11 . DOI:
10.1520/D5454-11R20.
50 lb ⁄MMSCF.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM 3.1.6 water dewpoint—the temperature (at a specified pres-
Standards volume information, refer to the standard’s Document Summary page on
sure) at which liquid water will start to condense from the
the ASTM website.
3 water vapor present. Charts of dewpoints versus pressure and
The last approved version of this historical standard is referenced on
www.astm.org. water content are found in Test Method D1142.
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D5454 − 11 (2020)
4. Significance and Use 5.1.4 Power Supply—Analyzers for field use will have
rechargeable or easily replaceable batteries. (Warning—
4.1 Water content in fuel gas is the major factor influencing
Analyzers for use in hazardous locations because of combus-
internal corrosion. Hydrates, a semisolid combination of hy-
tible gas must be certified as meeting the appropriate require-
drocarbons and water, will form under the proper conditions
ments.)
causing serious operating problems. Fuel heating value is
reduced by water concentration. Water concentrat
...