ASTM E1377-99(2022)

Standard Specification for Laboratory Glass Kjeldahl Flasks

ABSTRACT
This specification provides standard dimensional requirements for glass Kjeldahl flasks for nitrogen digestion analysis. The ungraduated flasks, Type I, and graduated flasks, Type II, shall conform to the specified capacities. Flasks shall be made of borosilicate glass, conforming to the required maximum residual stress, tolerance of volumetric accuracy, and dimensions.
SCOPE
1.1 This specification provides standard dimensional requirements for glass Kjeldahl flasks for nitrogen digestion analysis.  
1.2 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Aug-2022
• ICS: 71.040.20 - Laboratory ware and related apparatus
• Technical Committee: E41 - Laboratory Apparatus
• Drafting Committee: E41.01 - Laboratory Ware and Supplies

Relations

• Refers: ASTM E438-92(2024) - Standard Specification for Glasses in Laboratory Apparatus
• Effective Date: 01-Feb-2024
• Refers: ASTM E694-18(2024) - Standard Specification for Laboratory Glass Volumetric Apparatus
• Effective Date: 01-Feb-2024
• Refers: ASTM E920-97(2019) - Standard Specification for Commercially Packaged Laboratory Apparatus
• Effective Date: 01-Jul-2019
• Refers: ASTM E694-18 - Standard Specification for Laboratory Glass Volumetric Apparatus
• Effective Date: 01-Jan-2018
• Refers: ASTM E438-92(2018) - Standard Specification for Glasses in Laboratory Apparatus
• Effective Date: 01-Jan-2018
• Refers: ASTM E920-97(2013) - Standard Specification for Commercially Packaged Laboratory Apparatus
• Effective Date: 01-Nov-2013
• Refers: ASTM E1157-87(2018)e1 - Standard Specification for Sampling and Testing of Reusable Laboratory Glassware
• Effective Date: 01-Dec-2011
• Refers: ASTM E147-61(2011) - Standard Specification for Apparatus for Microdetermination of Nitrogen by Kjeldahl Method
• Effective Date: 01-Dec-2011
• Refers: ASTM E1157-87(2011) - Standard Specification for Sampling and Testing of Reusable Laboratory Glassware
• Effective Date: 01-Dec-2011
• Refers: ASTM E438-92(2011) - Standard Specification for Glasses in Laboratory Apparatus
• Effective Date: 01-Dec-2011
• Refers: ASTM E1133-86(2010) - Standard Practice for Performance Testing of Packaged Laboratory Apparatus for United States Government Procurements
• Effective Date: 01-Sep-2010
• Refers: ASTM E694-99(2010) - Standard Specification for Laboratory Glass Volumetric Apparatus
• Effective Date: 01-Jul-2010
• Refers: ASTM E921-97(2010) - Standard Specification for Export Packaged Laboratory Apparatus
• Effective Date: 15-May-2010
• Refers: ASTM E671-98(2010) - Standard Specification for Maximum Permissible Thermal Residual Stress in Annealed Glass Laboratory Apparatus
• Effective Date: 01-Apr-2010
• Refers: ASTM E920-97(2008) - Standard Specification for Commercially Packaged Laboratory Apparatus
• Effective Date: 01-Nov-2008

Overview

ASTM E1377-99(2022): Standard Specification for Laboratory Glass Kjeldahl Flasks provides comprehensive requirements for the dimensions and material performance of glass flasks used in the Kjeldahl method of nitrogen digestion analysis. Developed by ASTM International, this standard ensures consistent quality and performance for both ungraduated (Type I) and graduated (Type II) Kjeldahl flasks. The specification is recognized internationally and aligns with the ISO principles for standardization, supporting uniform laboratory practices worldwide.

Key Topics

• Flask Types and Capacities: The standard covers two main types of Kjeldahl flasks:
  • Type I (Ungraduated): Available in 100 mL, 300 mL, 500 mL, 650 mL, and 800 mL sizes.
  • Type II (Graduated): Includes an 800 mL flask graduated at 1000 mL.
• Material Requirements: Flasks must be made from borosilicate glass that meets ASTM E438 Type I, Class A standards, ensuring excellent chemical resistance and durability during high-temperature nitrogen digestion processes.
• Dimensional Specifications: Detailed maximum/minimum dimensions for body and neck diameters, wall thickness, overall height, and stopper sizes are specified, ensuring compatibility with laboratory equipment and safety in use.
• Thermal Stress Control: The standard limits residual thermal stress according to ASTM E671, reducing the risk of breakage during heating cycles.
• Design and Markings:
  • All flask necks must be circular and perpendicular to the flask body, with standardized top finishes (tooled or beaded).
  • Flasks are permanently marked with the manufacturer's name or trademark and nominal or actual capacity.
  • Provided space on the neck allows for laboratory pencil markings.
• Volumetric Accuracy: Graduated flasks (Type II) must conform to the volumetric accuracy tolerances set by ASTM E694.
• Annealing and Appearance: Requirements address proper annealing for glass strength and define visual appearance criteria.

Applications

This specification is critical for laboratories performing nitrogen analysis using the Kjeldahl method, commonly applied in:

• Analytical Chemistry: Accurate quantification of nitrogen content in chemicals, pharmaceuticals, and biological samples.
• Food and Agricultural Testing: Determining protein content in food, animal feed, and soil samples.
• Environmental Science: Measurement of nitrogen compounds in water and waste samples.
• Research Laboratories: General nutrient and element analysis requiring precise and reliable glassware.

The use of flasks produced to ASTM E1377-99(2022) ensures repeatable results, minimizes laboratory errors, and meets regulatory compliance for quality systems and audits.

Related Standards

Several referenced standards support the implementation and compliance with ASTM E1377-99(2022):

• ASTM E147: Apparatus for Microdetermination of Nitrogen by Kjeldahl Method (covers smaller flask sizes)
• ASTM E438: Glasses in Laboratory Apparatus (defines borosilicate glass requirements)
• ASTM E671: Maximum Permissible Thermal Residual Stress in Annealed Glass Laboratory Apparatus
• ASTM E694: Laboratory Glass Volumetric Apparatus (volumetric accuracy tolerances)
• ASTM E1157: Sampling and Testing of Reusable Laboratory Glassware
• ASTM E920/E921/E1133: Specifies packaging, export, and performance testing of laboratory glassware

Summary

Meeting ASTM E1377-99(2022) requirements for laboratory glass Kjeldahl flasks assures laboratories of consistent, safe, and reliable products, essential for accurate nitrogen digestion analysis. Selecting compliant glassware enhances laboratory quality, supports international trade, and promotes standardization in scientific testing and research.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E1377 −99 (Reapproved 2022)
Standard Specification for
Laboratory Glass Kjeldahl Flasks
This standard is issued under the fixed designation E1377; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 300 mL
500 mL
1.1 This specification provides standard dimensional re-
650 mL
quirements for glass Kjeldahl flasks for nitrogen digestion
800 mL
analysis.
3.1.1 Sizes 10 mLand 30 mLand the Soltys style 30 mLare
1.2 This international standard was developed in accor-
covered under Specification E147 and are not included herein.
dance with internationally recognized principles on standard-
3.2 Graduated Flasks, Type II, shall be of the following
ization established in the Decision on Principles for the
capacity:
Development of International Standards, Guides and Recom-
800 mL, graduated at 1000 mL
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
NOTE 1—The term millilitre (mL) is commonly used as a special name
for the cubic centimetre (cm ) and similarly the litre (L) for 1000 cubic
2. Referenced Documents
centimetres, in accordance with the International System of Units (SI).
2.1 ASTM Standards:
4. Material and Annealing
E147 Specification forApparatus for Microdetermination of
Nitrogen by Kjeldahl Method
4.1 Flasks shall be made of borosilicate glass conforming to
E438 Specification for Glasses in Laboratory Apparatus
the requirement of Type I, Class A of Specification E438.
E671 Specification for Maximum Permissible Thermal Re-
4.2 Maximum residual thermal stress shall conform to
sidual Stress in Annealed Glass Laboratory Apparatus
Specification E671.
E694 Specification for Laboratory Glass Volumetric Appa-
ratus
5. Appearance
E920 Specification for Commercially Packaged Laboratory
Apparatus
5.1 The general appearance of the flasks shall conform to
E921 Specification for Export Packaged Laboratory Appa-
Fig. 1.
ratus
E1133 Practice for Performance Testing of Packaged Labo-
6. Design
ratory Apparatus for United States Government Procure-
6.1 Necks on all flasks shall be circular in cross section, and
ments
shall be perpendicular to center of flask body.
E1157 Specification for Sampling and Testing of Reusable
Laboratory Glassware 6.2 Top finish of flask shall not be belled over 2 in. from the
top. Top shall be tooled or beaded.
3. Classification
6.3 Interior neck finish of sizes 500 and 800 mL may be
3.1 Ungraduated Flasks, Type I, shall be of the following
tooled to accept special rubber stopper especially made for
capacities:
Kjeldahl flasks.
100 mL
6.4 Bottom of flask shall be hemispherical in shape, while
top has a curved taper to point of junction with the flask neck.
This specification is under the jurisdiction of ASTM Committee E41 on
(See Fig. 1.)
Laboratory Apparatus and is the direct responsibility of Subcommittee E41.01 on
Laboratory Ware and Supplies.
6.5 Wall thick
...