What is ISO 24117 about?
The international standard ISO 24117 provides you with a generic definition and classification of glass clarity to permit a global understanding of consumer quality requirements, with a corresponding method to measure glass clarity.
ISO 24117 establishes requirements for the use of the glass designations “clear glass” and “ultra-clear glass” for non-coloured glass items according to their clarity and iron content. ISO 24117 specifies a procedure for measuring the clarity of glass items by means of a spectrophotometer.
ISO 24117 covers mineral glasses, and glass items where a part is not covered by coating or decoration and is therefore available for sampling. ISO 24117 is applicable to the use of glass as tableware, giftware, jewellery and luminaries.
NOTES-
ISO 24117 is not applicable to the use of glass in the context of building, watches, containers, medicine and laboratories, and to other technical uses of glass.
ISO 24117 does not concern lead crystal categories as defined in EU Council Directive 69/493/EEC, which has its own characteristics with respect to density and refraction index.
Who is ISO 24117 for?
ISO 24117 on glass clarity test is useful for:
- Manufacturers of glass and glass-made products
- Glass industries
- Quality control professionals
- Inspection and certification bodies
- Testing laboratories
Why should you use ISO 24117?
Clear and ultra-clear glass products are used extensively worldwide for tableware, giftware, jewellery, luminaries.. There is no international standard establishing requirements for the use of the designations ‘clear-glass’ and ‘ultra-clear glass’ for non-cloured glass items according to their clarity. This is why ISO 24117 provides you with test methods and classification for glass clarity that is needed to enable precise product characterization and facilitate commercial exchanges through transparency of information.
For glass clarity, spectrophotometric measurement is performed in accordance with CIE 15:2004 with a predefined choice of illuminate and observer. Measurement on the sample at two different thicknesses permits calculation of internal transmission for a defined intermediate thickness and indicates glass clarity irrespective of the refractive index value.
ISO 24117 includes the procedure which describes a method for determining lightness and chroma, which helps to classify glass items in accordance with the specifications for ultra-clear glass and for clear glass.
