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Fees for the regular services described in these schedules are isted in Part 8 of this publication. Fees for z items and other services ave not been fixed and charges will be made for actual costs incurred. pon request, estimates will be furnished for specific tasks which should provide a close approximation of actual cost.

221.111 Laboratory thermometers.

Direct inquiries to, and mark shipments for the attention of: Temperature Section, PHYS - A241, National Bureau of Standards, Washington, JC 20234. Telephone: 301-921-2087.

Only thermometers

accepted for test.

identified uniquely by serial number will be

Item

Description

221.111a

Testing at points from 0 to 100 °C, inclusive, or from 32 212 'F, inclusive, for each point tested.

221.111b Testing at points from 101 to 300 °C, inclusive, or from °F, inclusive, for each point tested.

221.111c

221.111d

to

213

to

601 to

Testing at points from 301 to 500 °C, inclusive, or from
950 °F, inclusive, for each point tested.
Testing at points from -1 to -110 °C, inclusive, or from 31 to
-166 °F, inclusive, for each point tested.

oxygen, or liquid nitrogen (-183 to

221.111e Testing in liquid air,
-196 °C), for each point tested.
Calorimeter thermometers.

221.111f

Beckman thermometers, with 5° or

221.111g

221.111h

221.111i

scale, testing at 0.5° intervals by comparison with precision standards.

When instruments submitted are found to be unsuitable for test or unreliable a charge will be made to cover the cost of the work done. Minimum fee.

Preliminary examination for foreign material in the mercury column and bulb and for a separated mercury column will be made as required. Separated mercury column will be reunited provided this can be accomplished readily. Maximum fee.

221.111z Special measurements not covered by this schedule.

cators.

(a) Direct inquiries to, and mark shipments for the attention Temperature Section, PHYS B228, National Bureau of Standards,

ington, DC 20234. Telephone: 301-921-2069.

(b) Only the bare wires are required in order to perform the mocouple calibrations in this schedule. It is preferable not to send lating and protecting tubes as the rate of breakage of these in ment is high. If the thermocouple is furnished mounted (as in a ection-tube assembly) a charge of $5 will be made for dismantling the ting and the various parts will be returned to the sender without reasling them.

(c)

ead wire.

Thermocouple length requirements listed below are exclusive
Lead wire need not be sent with thermocouples.

(d) All thermocouple calibration data furnished in reports n the basis of a reference junction temperature of 0 °C or 32 °F.

will

(e) The calibration or test of an article will not be undertaken in our opinion, the article will not yield the specified accuracy or if ossesses such unusual characteristics as to prevent the carrying out of calibration or test at a reasonable cost. Only unused base-metal mocouples and thermocouple materials will be accepted for test.

em

112 a

112b

Description

High-temperature thermocouples and thermocouple materials. Minimum length 24 in. Corresponding values of emf and temperature at 4 to 15 points in the range 0 to 1450 °C (32 2650 °F).

to

The uncertainties in the values of temperature corresponding to the values of emf reported for platinum versus platinum-rhodium thermocouples are estimated not to exceed 0.5 degree in the to 1100 °C and increase to not more than 2 degrees at 1450 °C. Results for platinum versus platinum-10 percent rhodium thermocouples are given at 1-degree intervals over the entire range 0 to 1450 °C.

range

The uncertainties in the values of temperature corresponding
the values of emf reported for base-metal thermocouples are
estimated not to exceed 1 °C. Base-metal thermocouples are not
tested above 1100 °C (2000 °F).

Thermocouple materials are tested against platinum thermoelectric standards maintained by the Bureau.

High-temperature thermocouples and

thermocouple materials. Calibration as per item 221.112a at less than four points, per point.

221.112c

221.112d

221.112e

221.112f

221.112g

221.112h

Platinum versus platinum-10 percent rhodium thermocouples. The thermocouple shall be at least 36 in. long and made of wire not less than 0.014 in. in diameter. Emf of a thermocouple at any of the following temperatures: 1063 °C (gold point), 960.8 °C (silver point), 630.5 °C, 419.5 °C (zinc point). Calibration uncertainty estimated not to exceed 2μV (about 0.2 °C).

Platinum versus platinum-10 percent rhodium thermocouples. The thermocouple shall be at least 36 in. long and made of wire not less than 0.014 in. in diameter. Primary calibration at all of the temperatures listed in item 221.112c plus a table of corresponding values of emf and temperature at 1-degree intervals in the range 0 to 1450 °C.

in

Uncertainty in emf reported for the fixed point temperatures is
estimated not to exceed 2uV. Uncertainties in values given
the tables are estimated not to exceed 0.3 °C in the range 0 to
1100 °C and increase to not more than 2 degrees at 1450 °C.
If the submitted thermocouple meets the requirements of the
International Practical Temperature Scale for standard thermo-
couples [see the International Practical Temperature Scale of
1948 by H. F. Stimson, J. Res. NBS 65A, 139 (1961)], a
quadratic equation fitted at 1063, 960.8, and 630.5 °C also
will be furnished.

High-temperature thermocouples and thermocouple materials. Interpolated corresponding values of emf and temperature as per item 221.112a, per point.

Base-metal thermocouples. Minimum length 36 in. Corresponding values of emf and temperature with an uncertainty of 0.1 °C in the range 0 to -110 °C, per point.

Minimum calibration per thermocouple, two points.

Base-metal thermocouples. Minimum length 36 in. Corresponding values of emf and temperature with an uncertainty of about 0.1 in the range 0 to 300 °C and with an uncertainty of about 0.2° above 300 °C, per point.

Minimum calibration per thermocouple, two points.

in. Corresponding

Base-metal thermocouples. Minimum length 36
values of emf and temperature with an uncertainty of about 0.19
in the range -183 to 196 °C, per point.

Minimum calibration per thermocouple, two points.

221.112i

Pyrometer indicators. Calibration of single scale or meter single dial of potentiometer (reference junction compensator counting as a dial).

of

ndicators.

f:

(a) Direct inquiries to, and mark shipments for the attention Temperature Section, PHYS B228, National Bureau of Standards,

ashington, DC 20234. Telephone: 301-921-2069.

(b) Only the bare wires are required in order to perform the hermocouple calibrations in this schedule. It is preferable not to send nsulating and protecting tubes as the rate of breakage of these in hipment is high. If the thermocouple furnished mounted (as in a rotection-tube assembly) a charge of $5 will be made for dismantling the ounting and the various parts will be returned to the sender without reasembling them.

(c)

f lead wire.

Thermocouple length requirements listed below are exclusive
Lead wire need not be sent with thermocouples.

(d) All thermocouple calibration data furnished in reports

e on the basis of a reference junction temperature of 0 °C or 32 °F.

will

(e) The calibration or test of an article will not be undertaken f, in our opinion, the article will not yield the specified accuracy or if t possesses such unusual characteristics as to prevent the carrying out of he calibration or test at a reasonable cost. Only unused base-metal hermocouples and thermocouple materials will be accepted for test.

Item

21.112a

21.112b

Description

High-temperature thermocouples and thermocouple materials.
Minimum length 24 in. Corresponding values of emf and
temperature at 4 to 15 points in the range 0 to 1450 °C (32
2650 °F).

to

The uncertainties in the values of temperature corresponding to the values of emf reported for platinum versus platinum-rhodium thermocouples are estimated not to exceed 0.5 degree in the range 0 to 1100 °C and increase to not more than 2 degrees at 1450 °C. Results for platinum versus platinum-10 percent rhodium thermocouples are given at 1-degree intervals over the entire range 0 to 1450 °C.

The uncertainties in the values of temperature corresponding to the values of emf reported for base-metal thermocouples are estimated not to exceed 1 °C. Base-metal thermocouples are not tested above 1100 °C (2000 °F).

Thermocouple materials are tested against platinum thermoelectric standards maintained by the Bureau.

High-temperature thermocouples and

thermocouple materials. Calibration as per item 221.112a at less than four points, per point.

221.113c

221.113d

221.113e

221.113f

21.113g

Calorimetric type platinum resistance thermometers. Calibration at the triple point of water and at approximately 50 and 100 °C. Table will be furnished with entries at 1-degree intervals.

cali

Capsule-type platinum resistance thermometers. Comparison
bration over the range from 12 to 90 °K. Results will be in
the form of a table with entries at 0.1-degree intervals.
Additional tables are not available unless requested at the time
of test (see item 221.113f).

Determination of the average temperature coefficient of electri-
cal resistance over the interval 0 to 100 °C. Minimum length,

16 in.

Samples must have a resistance of at least 0.1 ohm per foot at the ice point.

Each additional table expressing the results of tests under items 221.113a, b, or c.

Additional tables under item 221.113d are not available unless requested at the time of test.

Item 221.113f if requested at the same time as the test of the thermometer under item 221.113a, b, c, or d.

21.113h Capsule-type platinum resistance thermometers. Mounting this type of thermometer for test under item 221.113 a or b (not applicable to item 221.113d).

21.113y

When instruments submitted are found to be unsuitable for test or unreliable, a charge will be made to cover the cost of the work done.

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