ASTM E1046-85 (R2021) pdf free download.Standard Specification for Glass Westergren Tube, Disposable.
1.1 This specification covers a disposable tube used for measuring the erythrocyte sedimentation rate, ESR (the suspension stability of red cells in diluted, anti-coagulated human blood).
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
4.1.1 Type I—standard Westergren tube to be used in conventional racks only, and
4.1.2 Type 11—self-zeroing tubes to be used with racks designed with convenient disposable tube features.
5. Materials
5.1 Glass—The tubes made to this specification shall be fabricated from borosilicate glass. Type I. Class B. or soda lime glass. Type II. in accordance with Specification E438.
6. Physical Requirements
6. 1 Design, Type I and II—The Westergren tube shall be made of one-piece construction from tubing that is straight and of uniform bore. The ends of the tube shall he cut at right angles to the axis of the tube and fire polished.
6.1.1 Type II only—Each tube shall have an ahsorhant cotton plug inserted in the tube with the bottom edge of the plug aligned with the 0 mm calibration line. The alignment of the plug to the calibration line should not vary by more than 1 mL. The plug must be capable of supporting a 200 mm vertical column of water when the plug has been thoroughly soaked.
Note 1—With possible printing scale variation and cotton plug alignment to the calibration line variation, the bottom of the cotton plug is to be located 200 ± 1 mm from the bottom of the tube.
6.2 Workmanship—The tube shall be free as possible from visible defects which would detract from its appearance or impair its serviceability when viewed by the human eye under normal room lighting. Self-zeroing tubes are to be used with racks designed with convenient disposable tube features.
6.3 Dimensions—Dimensions and tolerances shall be in accordance with Fig. I. The uniformity of the bore shall he ±0.15 mm throughout the tube. The tube shall have an inscribed graduated scale extending over the lower 200 ± 1.0mm of the tube. The marker’s or vendor’s name or mark shall he inscribed on the tube in a selected location. Inscription of the word bWestcrgren on the tube is optional. Type II tubes may be made of varied lengths from 230 to 243 mm long with the selected length within this range confined to a ±1 mm tolerance.
6.4 Graduation Lines—Thickness of graduation lines may vary in uniformity but shall not exceed 0.4 mm in thickness.