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ASTM E694-2018 pdf free download

ASTM E694-2018 pdf free download.Standard Specification for Laboratory Glass Volumetric Apparatus
1. Scope
1.1 This specification covers general requirements common to glass volumetric apparatus. Specific dimensions and toler- ances for applicable instruments are given in other specifica- tions as cited throughout this specification. Glass must conform to Specifications E438 and be calibrated in accordance with Practice E542. 1.1.1 Class A—Each instrument shall be marked with the letter A to signify compliance with applicable construction and accuracy requirements. Instruments may be marked with an identification marker (serial number) at the option of the manufacturer. 1.1.2 Class B—General purpose instruments are ofthe same basic design as Class A. However, volumetric tolerances for Class B instruments shall be within twice the specified range allowed for Class A unless otherwise specified. 1.2 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. General Requirements
3.1 Units ofVolume—The unit of volume shall be the cubic centimetre (cm 3 ) or, in special cases, the cubic decimetre (dm 3 ) or cubic millimetre (mm 3 ). N OTE 1—The term millilitre (mL) is commonly used as a special name for the cubic centimetre (cm 3 ) and, similarly the litre for the cubic decimetre (dm 3 ) and the microlitre (µL) for the cubic millimetre (mm 3 ), in accordance with the International System of Units (SI). 3.2 Standard Temperature—The standard reference temperature, that is, the temperature at which the article of volumetric glassware is intended to contain or deliver its nominal volume (nominal capacity), shall be 20°C. N OTE 2—When it is necessary in tropical countries to work at an ambient temperature considerably above 20°C, and it is not desired to use the standard reference temperature of 20°C, it is recommended that a temperature of 27°C be adopted. 3.3 Material and Annealing—Volumetric glassware shall be constructed of glass of suitable chemical and thermal proper- ties. It shall be as free as possible from visible defects and shall conform to Specification E671. 3.4 Limit of Error—On an article having multiple gradua- tion lines, the limit of volumetric error may occur at any graduation line unless otherwise specified. For example, on a 100-mL graduated cylinder having a limit of error of 61.00 mL, the volume at 10 mL could range from 9.00 to 11.00 mL. N OTE 3—The limit ofvolumetric error specified for any article designed for delivery shall not be less than four times the standard deviation determined experimentally by an experienced operator from a series of at least twenty replicate determinations of delivered capacity on the same article, carried out strictly in accordance with the method specified for that article. 3.5 Stability—Vessels provided with a flat base shall stand firmly thereon without rocking when placed on a level surface and, unless specified otherwise, the axis of the graduated portion of the vessel should be vertical. Except for special cases, vessels shall not topple when placed empty and without a stopper on a surface inclined at an angle to the horizontal of 15° for sizes 25 cm 3 or greater and 10° for vessels less than 25 cm 3 . Vessels provided with a base that is not circular shall meet this requirement in all directions. 3.6 Stoppers and Stopcocks: 3.6.1 Stoppers—Glass stoppers should be ground so as to be interchangeable, in which case the ground portions shall be in accordance with Specification E675. Stoppers of a suitable inert plastics material may be permitted as an alternative to glass. In such cases, the glass socket into which the stopper fits shall be in accordance with Specification E675. All stoppers shall bear a proper size identification. 3.6.2 Stopcocks—Stopcocks and similar devices shall be designed to permit smooth and precise control of outflow and to prevent a rate of leakage greater than that allowed in the specification for the article and shall be in accordance with Specification E675. Stopcocks shall be made from glass or from suitable inert plastics material.

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