212.143d Conformity to chromaticity of standard, sample and standard illuminated normally by artificial daylight or by incandescentlamp light, chromaticity difference expressed in terms of chromaticity coordinates on fundamental colorimetric coordinate system, one sample relative to a standard. 212.143e Each additional sample relative to the same standard. 212.143f Each additional sample relative to an additional standard. 212.143g Color temperature of 120-V, screw-base incandescent lamp, voltage for specified color temperature, current for neighboring voltage to check permanence, one color temperature, each lamp. 212.143h 212.143i Color temperature standard supplied from stock, 100-W mediumscrew base or 500-W mogul-screw base projection type lamp, calibrated for 2,854 °K, one lamp each. Same, calibrated for any one other specified color temperature, one lamp each. 212.143j Each additional color temperature on the same lamp. 212.144 Opacimetry. •K, Opacity of diffusing glass by contrast-ratio (ratio of luminous reflectance factor with with black backing to that with white backing), illumination nearly perpendicular to surface of glass, reception of all reflected flux regardless of angle. Reflectance of white backing taken so as to accord with Bausch & Lomb type photoelectric opacimeter correctly adjusted to read contrast-ratio for thin samples with a white backing reflecting 0.915 relative to MgO (TAPPI test method T425m-60). Diffusing glass rectangles, 5 x 12 cm, supplied by the Bureau. 212.144a Each diffusing-glass opacity standard, opacity between 0.60 and 0.96 as desired. 212.144b Set of four diffusing-glass opacity standards, opacities approximately equal to 0.72, 0.79, 0.86, and 0.93. 212.144z Special measurements not covered by this schedule. scale Lovibond red glasses, determination of numeral on the AOCS tablished in 1961 by agreement with the Color Committee of the American 1 Chemists' Society, the value given being the effective value when the ven red glass is used in combination with a 35-yellow glass, each glass be engraved with the National Bureau of Standards test number and the meral found for the glass. 212.146 Signal glass limit glasses and IPL calibrating filters. or (a) Railroad, highway (traffic), and aviation signal glasses for e as chromaticity limits or transmittance standards in accord with ecifications approved by the cognizant technical association vernment agency will be issued when available. The report of calibration cludes chromaticity coordinates, luminous transmittance, or both as termined relative to national standard filters for the specified color mperature of source. (b) Instrument Panel Lighting (IPL) calibrating filters are ailable in 51-mm polished squares. They have the following designations pproximate chromaticity coordinates for color temperature 2,854 °K are own in parentheses): NBS 3056 (x=0.723, NBS 3056 (x=0.723, y=0.277), NBS 3114 (x=0.712, 0.288), NBS 3215 (x=0.698, y=0.302), and NBS 3648 (x=0.667, y=0.333). e NBS 3215 filters define the pale limit for airplane red instrument nel lighting and are usually used in pairs; the other types of filters sted are for calibrating photometers used for measuring panel luminance. Item 2.146a Signal limit glasses, each. 2.146b Description IPL calibrating filters, calibrated for chromaticity coordinates 2.146c Calibration for transmittance at an additional color temperature. 2.146z Special measurements not covered by this schedule. ) 212.151a Calibration of radiant energy meter for energy of 2537 Å. 212.151b Measurement of irradiance of 2537 Å, from sterilamp. germicidal 212.151z Special measurements not covered by this schedule. Length lamp or Direct inquiries to: of Standards, Washington, purchase orders Length Section, MET A211, National Bureau 20234. Telephone: 301-921-2731. Direct Administration Unit, National Bureau of Standards, Washington, DC 20234. Direct shipments to: Length Section, National Bureau of Standards, Route 70S and Gaithersburg, Maryland 20760. Item 212.211 Linear thermal expansion of solids. Description Quince Orchard Road, 212.211z Special measurements only are conducted in this category. Only those tests that cannot be carried out elsewhere will be accepted. 212.212 Gage blocks. (a) Test fee schedules in Section 212.212 include a statement of the accuracy to which measurements ordinarily are made; however, if the character of the defining defining surfaces of a gage block is not such as to warrant this accuracy, the report will show the accuracy actually obtained. All gage blocks submitted for test should be in substantially new block condition and each block should be marked with an identification number. (b) In shipping gage blocks extreme gage blocks extreme care should be taken both against corrosion and damage by contact with other gage bocks. A11 defining steel surfaces should be greased and the blocks padded with waxed paper or volatile rust inhibitor treated paper. A greased steel surface coming in contact with newspaper, wrapping paper (unwaxed), or excelsior is very likely to corrode. Sets of gage blocks should have packing inside the case and the case should be bound shut as the clasps open or break frequently during shipment. 2.212a 2.212b 2.212ab 2.212c 2.212d 2.212cd 2.212e 2.212f Determination of length to ±0.000004 in. and excessive errors in flatness and parallelism, for sizes from 0.100 in. to and including 1.000 in., in lots of 10 or more, each. Actual cost of calibration will be charged for smaller lots. Determination of length to ±0.000004, ±0.000005, and ±0.000006 in., respectively, for blocks from 1 to 2 in., 2 to 3 in., and 3 to 4 in. in length, and excessive errors in flatness and parallelism, in lots of three or more, each. Actual cost of calibration will be charged for smaller lots. Measurements as described under items a and b for usual 81-block set, per set. Extra blocks will be charged for under items a or e. Determination of length to ±0.000002 in. and excessive errors in flatness and parallelism, for sizes from 0.100 in. to and including 1.000 in., in lots of 10 or more, each. Actual cost of calibration will be charged for smaller lots. Determination of length to ±0.000002, ±0.000003, and ±0.000004 in., respectively, for blocks from 1 to 2 in., 2 to 3 in., and 3 to 4 in. in length, and excessive errors in flatness and parallelism, in lots of three or more, each. Actual cost of calibration will be charged for smaller lots. Measurements as described under items c and d for usual 81-block set, per set. Extra blocks will be charged for under items c or e. Determination of length to ±0.000003 in. and excessive errors in parallelism, for sizes from 0.010 in. to and including 0.090 in. in lots of 10 or more each. Blocks in this size range are usually warped and do not warrant calibration to a higher accuracy. In special cases, blocks 0.040 in. and thicker will be calibrated under item c if the errors in flatness and parallelism of the blocks are not excessive. Determination of length to ±0.000001 in. per inch of length and excessive errors in flatness and parallelism, for blocks of the following length: 5, 6, 7, 8, 10, 12, 16, and 20 in., in lots of three or more, each. Actual cost of calibration will be charged for smaller lots. 2.212z Special measurements not covered by this schedule. 212.213a 212.213b 212.213c of the Line standard 40 inches or less in length-determination Determination of any other single interval. Determination of equal submultiples of the length determined under item a or b, each. 212.213z Special measurements with accuracies greater than or less than that covered by this schedule. 212.214 Steel tapes. (a) Steel tapes are used for various types of long-interval length measurements. Some tapes, although of excellent quality and having application that that justifies NBS calibration, are not necessarily suitable for use as reference tapes. A reference tape should meet the following requirements: The tape should be a single flexible piece of flat metallic ribbon with all graduations marked directly on the face of the ribbon; principal graduations should be designated, except for zero when it is the starting graduation; and the total length correction should not exceed 0.1 in. per 100 ft (2 mm per 25 m) when supported on a horizontal flat surface under standard tension at 68 °F (20 °C). The standard tension is 10 lbs for tapes 25 to 100 ft in length (4.5 kg for tapes 10 to 30 m in length) and 20 lbs for tapes longer than 100 ft (9 kg for tapes longer than 30 m). (b) Steel tapes of either reference or special-purpose type accepted for calibration will be issued a Report of Calibration and will be assigned an NBS serial number for identification. A steel tape considered to be suitable as a reference tape will also also be engraved with a mark indicating the year of calibration. The length intervals reported will be for measurements made with tapes supported at specified points in the same horizontal plane, under specified applied tension, and at 68 °F (20 °C). Normally, the accuracy of reported lengths will be one part in 100,000 or 0.001 ft (0.0003 m), whichever is greater. Item 212.214a 212.214b Description Determination of the total length when supported throughout on a horizontal flat surface under standard tension, for a tape not exceeding 200 ft or 50 m in length. This is a standard test which will be made and charged for; to this amount must be added the fees for any additional tests. Determination of the total length on the reverse side of the tape when supported on a horizontal flat surface under standard tension, for a tape not exceeding 200 ft or 50 m in length. |