Labotec Logo
Advanced X-Ray Glass – Blocking the Ionising Radiation, not the View

Advanced X-Ray Glass – Blocking the Ionising Radiation, not the View

Date posted: February 17, 2016 // Glass

The ability of heavy metals, most commonly lead, to block the passage of ionising radiation has long been known. Radioactive isotopes used in medicine, for instance, are usually transported in lead-lined containers. Technicians and physicians engaged in the diagnostic or therapeutic use of X-ray equipment must routinely don lead-lined aprons, so as to eliminate the risk of infertility that is known to result from long-term, repeated exposures. In addition, cumulative exposure levels are monitored using special dosimeter badges worn by all employees at risk.

The thick concrete walls that were necessary between the apparatus and the operators once left patients unmonitored and isolated until the discovery that glass, when suitably manufactured, could also be rendered impervious to these potentially deadly rays. The immediate advantages of using such a material are obvious. It allows operators in hospital radiology and radiotherapy departments, research laboratories, manufacturing plants and nuclear power stations a totally unobstructed view of whomever or whatever is being subjected to the particular variety of ionising radiation in use.

The principle behind the manufacture of X-ray glass is simple enough and is just an extension of the long established use of this heavy metal to make decorative crystal items, which involves the introduction of at least 25% lead oxide into the molten material. This lowers its melting point and allows it to be worked for longer. In addition, it has the effect of increasing the refractive index and density, improving strength and clarity.

By contrast, in order to impede the passage of X-rays effectively, the molten glass requires to be mixed with a far higher percentage of lead oxide. A typical quality product will contain around 65% of the oxide to deliver maximum protection. Surprisingly, perhaps, even at such a high concentration, the product shows no significant reduction in the transmission of visible light and thus presents the ideal choice for use in almost all application in which both excellent visibility and the maximum level of protection are essentials.

The exceptionally dense nuclei of lead atoms and other heavy metals are due to the large number of neutrons and protons. These, when exposed, serve to repeatedly deflect incoming ions and thus dissipate the bulk of their energy.

Labotec Industrial Technologies is a leading supplier of X-ray glass in South Africa and we are probably best known among our end users for Schott RD50 radiation-resistant glazing. Conforming to all of the important international requirements for radiation shielding, it provides a crystal-clear medium that maintains a level of protection that is exceptional, even with the use of relatively thin panes. For a more complete set of performance specs, just call us.