ASTM E879-01

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: E 879 – 01
Standard Specification for
Thermistor Sensors for Clinical Laboratory Temperature
1
Measurements
This standard is issued under the fixed designation E879; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2.2 dumet, n—round, copper-coated 42% nickel-iron
wireintendedprimarilyforsealingtosoftglass.Alsoknownas
1.1 This specification covers the general requirements for
CuNiFe in some communities.
negative temperature coefficient thermistor-type sensors in-
3.2.3 insulation resistance, dc, n—the resistance at a speci-
tended to be used for clinical laboratory temperature measure-
fied direct-current voltage between the insulated leads of a
ments or control, or both, within the range from−10 to 105°C.
thermistor sensor and the metallic enclosure of the sensor, if
1.2 This specification also covers the detailed requirements
such an enclosure is present, or else between the sensor leads
for ASTM designated sensors.
and a conductive medium in which the sensor is immersed.
1.3 This standard does not purport to address all of the
3.2.4 qualificationtest,n—aseriesoftestsconductedbythe
safety concerns, if any, associated with its use. It is the
procuring agency or an agent thereof to determine conform-
responsibility of the user of this standard to establish appro-
ance of thermistor sensors to the requirements of a specifica-
priate safety and health practices and determine the applica-
tion, normally for the development of a qualified products list
bility of regulatory limitations prior to use.
under the specification.
2. Referenced Documents
3.2.5 response time, n—the time required for a sensor to
change a specified percentage of the total difference between
2.1 ASTM Standards:
its initial and final temperatures as determined from zero-
E344 Terminology Relating to Thermometry and Hydrom-
2
power resistances when the sensor is subjected to a step
etry
function change in temperature.
E563 PracticeforPreparationandUseofanIce-PointBath
2
3.2.6 time constant, n—the 63.2% response time of a
as a Reference Temperature
sensor that exhibits a single-exponential response.
F29 Specification for Dumet Wire for Glass-to-Metal Seal
3
3.2.7 zero-power resistance, n—the dc resistance of a de-
Applications
vice, at a specified temperature, calculated for zero-power.
3. Terminology
3.2.7.1 Discussion—Accurate zero-power resistance is ob-
tained by extrapolating to zero-power the resistance values
3.1 Definitions—The definitions given in Terminology
obtained from measurements at three or more levels of power
E344 shall apply to this specification.
with the sensor immersed in a constant temperature medium.
3.2 Definitions of Terms Specific to This Standard:
For the purpose of this specification, this is obtained from
3.2.1 dissipation constant, d, n—the ratio of the change in
˙ measurements at a single power level adjusted such that the
energydissipatedperunittime(power)inathermistor, DQ =
˙ ˙ power is not greater than one-fifth the product of the dissipa-
Q − Q ,totheresultanttemperaturechangeofthethermistor,
2 1
tion constant specified in Table 1 (see 3.2.1 and 7.3) and the
Dt= t − t .
2 1
appropriate tolerance requirement of Table 2. When making
˙
D Q
stability measurements, the power shall be kept constant.
d5 (1)
Dt
4. Classification
The dimensions of the dissipation constant are W/K.
For this specification, t is in the range from 20 to 38°C and
4.1 Thermistorsensorscoveredbythisspecificationshallbe
1
Dt=10°C.
classifiedwithatypedesignationcodethatincludestheASTM
detailed specification number followed by a descriptive code.
See Fig. 1.
1
This specification is under the jurisdiction of ASTM Committee E20 on
4.2 ASTM Specification Number—The ASTM specification
Temperature Measurement and is the direct responsibility of Subcommittee E20.08
number specifies uniquely the design and construction of the
on Medical Thermometry.
Current edition approved May 10, 2001. Published June 2001. Originally
sensor including the type designation if more than one type
published as E879–82. Last previous edition E879–93.
appears in the same specification.
2
Annual Book of ASTM Standards, Vol 14.03.
3
Annual Book of ASTM Standards, Vol 10.04.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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E 879
TABLE 1 Specification for ASTM Clinical Laboratory Thermistor Sensors
ASTM No. E 879 S B1N E 879 E B1N E 879 S B2N E 879 E B2N
Description Silicone Rubber Coated Glass Epoxy Coated Glass Probe Silicone Rubber Coated Glass Epo
...