ASTM E1379-90(2022)

Overview

ASTM E1379-90(2022) is the internationally recognized standard specification covering laboratory glass Dewar flasks. Established by ASTM International, this standard outlines material and performance requirements for Dewar flasks intended for general laboratory use. It specifies the proper construction using high-quality materials such as Type I, Class A borosilicate glass, and ensures all Dewar flasks conform to strict criteria for thermal stress, design, capacity, and dimensional accuracy.

By adhering to these guidelines, laboratories achieve consistent performance, safe handling of cryogenic or low-temperature substances, and reliability in various scientific settings. Values and measurements in the standard use SI units, promoting universal applicability and compliance.

Key Topics

• Materials: Dewar flasks must be manufactured from Type I, Class A borosilicate glass, conforming to ASTM E438 for glass quality and E671 for maximum residual thermal stress.
• Design Requirements:
  • Cylindrical shape with double walls.
  • Inner walls are silvered for optimal insulation.
  • Evacuated and sealed space between walls (to a specified vacuum level).
  • Flask bases constructed from aluminum alloy conforming to ASTM B85 A380.
  • Protective plastic mesh or plastisol coating over exposed glass.
• Capacity and Dimensions: Standard flask sizes include 265 mL, 665 mL, 1000 mL, 1900 mL, and 4300 mL, each with specified nominal dimensions for body diameter, height, and depth.
• Performance Criteria:
  • Appearance and finish must meet defined quality standards.
  • Flasks securely cemented into bases for protection.
  • Compliance with government and laboratory specifications for scientific glassware.
• Standardization Principles: Developed in line with global standardization principles, including the WTO’s Technical Barriers to Trade (TBT) Committee recommendations, ensuring broad international acceptance.

Applications

Laboratory glass Dewar flasks are essential tools for:

• Cryogenic and Low-Temperature Storage: Ideal for safely holding liquid nitrogen, dry ice, or other refrigerants in scientific and industrial settings.
• Sample Preservation: Used to maintain temperature-sensitive samples, reagents, or biological materials in research, clinical laboratories, and educational institutions.
• Thermal Experiments: Suitable for controlled thermal experiments, including calorimetry or thermal conductivity testing, where reliable insulation is crucial.
• Analytical and Testing Environments: Dewar flasks ensure consistent temperature control, benefiting applications in chemical analysis, biotechnology, pharmaceuticals, and environmental science.

Adopting ASTM E1379-90(2022) guarantees laboratories use Dewar flasks that deliver robust performance, meet safety requirements, and provide effective thermal insulation and protection.

Related Standards

The following standards are referenced within ASTM E1379-90(2022) and inform its requirements:

• ASTM E438 - Specification for Glasses in Laboratory Apparatus: Defines glass quality and classification for laboratory use.
• ASTM E671 - Specification for Maximum Permissible Thermal Residual Stress in Annealed Glass Laboratory Apparatus: Outlines acceptable stress limits to ensure glass durability.
• ASTM B85 (Alloy A380) - Specification for Aluminum-Alloy Die Castings: Specifies the material properties for aluminum bases used in Dewar flasks.

By following ASTM E1379-90(2022) and the related standards, organizations assure compatibility, safety, and reliability in laboratory glassware, supporting best practices in laboratory operations and scientific research.