Worldwide Glass Resources, Inc. - Glossary of Terms

Technical Information: Additional Resources : Glossary of Terms and Abbreviations

Glossary of Terms and Abbreviations

  • Anneal: to cool glassware from a determined temperature at a controlled rate in order to prevent or remove objectionable stresses.
  • Annealing Point (AP): the temperature corresponding to a rate of elongation of 0.0136 cm/min when measured by ASTM Method C 336, Test for Annealing Point and Strain Point of Glass by Fiber Elongation.  This test prescribes a rate of cooling of approximately 4 C/min with a fiber of approximately 0.065 cm in diameter, and a suspended load of 1000 g.  The annealing point numerically approximates log=13.0 poises, where internal stress is substantially relieved in a few minutes.
  • Borosilicate Glass: any silicate glass having at least 5% of boric oxide.  The boric oxide makes the glass resistant to extreme temperatures and chemical corrosion.  Type I borosilicate has the least pH shift of any glass.  It is highly resistant to water, neutral and acid solutions, concentrated acids and acid mixtures, and to chlorine, bromine, iodine and organic substances. Its chemical resistance is superior to that of most metals and other materials, even during prolonged periods of exposure and at temperatures above 100 °C.  Type 1 clear borosilicate glass has a linear coefficient of expansion of 33 or 51.  Type 1 amber borosilicate glass has a linear coefficient expansion of 51.
  • Cap: outer component of closure which binds attaches to outer wall of the vial.
  • Closure: refers to the assembled combination of a cap and septa.
  • Durometer: measures the hardness of septa and is expressed in ° shore.  The higher the grade the harder the septa; the lower the grade, the softer the septa.  The softest liner is 45° shore A and the hardest 70° shore A.
  • EPA (Environmental Protection Association): American regulatory authority for standards and regulations for environmental analysis.
  • European Pharmacopoeia (Ph. Eur.; EP): a pharmacopoeia of the Council of Europe, whose mission is to promote public health by the provision of recognized common standards and ensure the quality of medicinal products and their components.
  • Expansion Coefficient: the average increase in length per unit length per °C change in temperature over the range of 0 to 300°C.  Since the expansion coefficient is affected slightly by annealing, the temperatures correspond to annealed glass.
  • Filling Point: the level which marks a glass bottle's nominal capacity.
  • Fire Polish: heating glass in a fire in order to make it glossy, smooth, or rounded.
  • Finish: the neck design and opening size of a vial.
  • Forming: the shaping of hot glass
  • GC: Gas Chromatography.
  • GC-MS: Tandem Gas Chromatography/Mass Spectrometry.
  • Glass: an inorganic product of fusion that has cooled to a rigid condition without crystallizing.
  • GPI (Glass Packaging Institute): An organization composed of glass manufacturers to set policies and standards.
  • HPLC: High Performance Liquid Chromatography.
  • HRV (High Recovery Vial): designed for maximum retrieval of sample from inside a vial.
  • Insert: sample container placed inside a vial to limit the sample volume inside the vial.
  • Japanese Pharmacopeia (JP): established to regulate the properties and quality of drugs by the Minister of Health, Labor and Welfare.  The JP consists of General Notices, General Rules for Crude Drugs, General Rules for Preparations, General Tests, Processes and Apparatus and Official Monographs.
  • LC: Liquid Chromatography.
  • LC-MS: Tandem Liquid Chromatography/Mass Spectrometry.
  • Lehr/Leer: a long, tunnel shaped oven used to annealing glass by continuous passage.
  • Melting Temperature: the range of furnace temperatures within which melting takes place at a commercially desirable rate, and at which the resulting glass generally has a viscosity of 1015 to 1025 poises.  For purposes of comparing glasses, it is assumed that the glass of melting temperature has a viscosity of 102 poises.
  • MS: Mass Spectrometry.
  • PE (Polyethylene): further classified as low-density, is a flexible translucent plastic.
  • PP (Polypropylene): a rigid plastic that is translucent or may be tinted to provide colored material.
  • Pre-Slit:  septa is cut through, in order to offer a penetration aid to the needle.  There are several Pre-Slit styles, including a simple slit, a cross-slit, or a starburst slit.
  • PTFE (Polytetrafluoroethylene): the most versatile of the plastics and exhibits excellent chemical resistance.
  • Seed: an extremely small gaseous inclusion of glass.
  • Septa: inner component of closure which lines the cap and makes contact with the sample
  • Silanization: the glass surface is chemically treated such that active sites are deactivated, allowing for more accurate quantitative analysis.
  • Softening Point (SP): the temperature at which a uniform fiber, 0.55 to 0.75 mm in diameter and 235 mm in length, elongates under its own weight at a rate of 1 mm/min when the upper 100 mm of its length is heated in the manner prescribed in ASTM Method C338.  Test for Softening Point of Glass at a rate of approximately 5 C/min.  For glass of density near 2.5, this temperature corresponds to a viscosity of 1076 poises.
  • SPME: Solid Phase Micro Extraction.
  • Stones: an imperfection of crystalline contaminations in glass.
  • Strain Point (SP): the temperature corresponding to a rate of elongation of 0.00043 cm/min when measured by ASTM Method C 336.  This test prescribed a linear extrapolation of the data obtained in the annealing point determination to the above designated rate.  Internal stress is substantially relieved at the strain point in a few hours.
  • Stress: any condition of tension or compression existing within the glass, particularly due to incomplete annealing, temperature gradient, or a lack of homogeneity.
  • Thermal Shock Resistance: the ability to withstand sudden heating, cooling, or both without causing defect.
  • TPX: a very low density plastic which has greater transparency than polypropylene.  It has excellent chemical resistance and low moisture absorption.
  • UHPLC: Ultra-High Performance Liquid Chromatography.
  • United States Pharmacopeia (USP): a non-governmental, official public standards-setting authority for prescription and over-the-counter medicines and other healthcare products manufactured or sold in the United States. USP also sets widely recognized standards for food ingredients and dietary supplements.
  • Vial: sample container for analysis.
  • Working Range: the range of surface temperature in which glass is formed into ware in a specific process.  The "upper end" refers to the temperature at which the glass is ready for working (generally corresponding to a viscosity of 103 to 104 poises), while the "lower end" refers to the temperature at which it is sufficiently viscous to hold its formed shape (generally corresponding to a viscosity greater that 106 poises).  For comparative purposes, when no specific process is considered, the working range of glass is assumed to correspond to a viscosity range from 104 to 1076 poises.
  • Young's Modulus:  the modulus of elasticity.  The stress required to produce a unit change of length.