Gammatex is used in the sterilisation industry as qualitative process indicators for the gamma irradiation sterilisation process.

Gammatex sterilization indicators undergo a simple yellow to red colour change when exposed to gamma radiation. They are coated labels, which serve as Class 1 process indicators, manufactured in compliance with ISO 11140-1:2005 “Sterilization of health care products – Chemical indicators”.

What does it mean?

Many items in healthcare and catering have to be sterilised between each use. Examples of items often sterilised are operating theatre gowns, surgical instruments, bedding and so on. Items like these are used continually all over the world, and they are sterilised by exposing them to a harmless dose of gamma irradiation.

In order to ensure the small dose is sufficient to sterilise the equipment, Gammatex™ labels are applied. The change of colour from yellow to red indicates that they have been exposed to sufficient radiation to ensure sterilisation.

Gammatex is often applied to a blank label to form a ‘Gammastripe’ label.

What are Gammastripe labels?

Gamma stripe labels are a combination of a standard paper box label incorporating a gamma/e-beam indicator panel within it construction.

The labels can be printed with your normal product identification information, LOT and batch text using your existing printer.

Due to its construction, the gamma panel will not fall off the label as is the case with some secondary applied indicator dots. Gammastripe labels present a much larger visual indication of processed and non-processed products.


  • Increase in efficiency – One label satisfies two processes. Batch identification and Sterilisation visual confirmation.
  • Huge saving in packaging labour – Secondary gamma indicator labels do not need to be applied.
  • One label carries all product information and incorporates the gamma indicator panel – This ensures elimination of customer complaints for non-applied indicators.
  • Improved efficiency as the box label can be pre-printed in house with LOT and Batch information.
  • Gives a much larger visual indication panel for processed and non-processed identification.
  • Labels can be manufactured for either direct thermal or thermal transfer over printing.
  • No costly additional hardware as the label can be run on your current overprinting box label printer.


  • Manufactured within and ISO9001:2008 accredited manufacturing facility in the UK.
  • Manufactured in compliance with ISO 11140-1:2005 specification.
  • Suitable for both Gamma and e-beam sterilisation processes.
  • Labels can be made to your custom size.
  • Labels can carry your company logo or additional marketing information asserting your product brand awareness.

Self-adhesive labels suitable for overprinting that also incorporate a Gamma / e-beam sensitive indicator

There are 3 standard sizes, but large users can have a fully customised design to suit end user requirements. They can also incorporate a company logo for added marketing and standard print information if required.

Gammatex now offer a dual Gamma / e-beam indicator incorporated within the convenience of a Direct Thermal or Thermal Transfer printable label.

They incorporate an 8mm wide Gamma / e-beam indicator strip that changes from yellow to red.

Labels can be provided with pre-printed data or supplied to end users as blanks ready for your on-demand print requirement. This eliminates the need for secondary label application for sterilisation validity visual recognition where individual lot/batch information is necessary.

Gamma Stripe Labels are compatible with most thermal printers and can be applied using automated label applicators.

Gamma Stripe Labels can be used as part of the validation process for Quality Control and Inventory processing.

They incorporate an 8mm wide Gamma / e-beam indicator strip that changes from yellow to red beginning at 10 kGy dosage, with a darkening depth of colour as the dosage level is increased.

Standard Sizes


    • 48.25mm x 23.4mm overall label dimension
    • 40.25mm x 23.4mm overprint area
    • 8mm x 23.4mm Gamma / e-beam indicator strip
    • Supplied in rolls to suit application


 “Working with Mercian Labels (who are providing essential sterilisation dots for our products – which change colour when in contact with irradiation) couldn’t be easier or smoother. Mercian are quick to react to our business needs and requirements, providing a consistent supply of a high quality product.” 

Nitritex Ltd – 1 October 2018

“ Mercian Labels have become a valued supplier, not just for labels but also for their keen support and development of label solutions unique to our business. These labels have given us attractive alternatives to standard labels, satisfying customer and internal requirements in the process. The marriage of Gammatex technology to our varying label needs is just one area where Mercian Labels have excelled in their interest, development and supply. Since the introduction of the piggyback four-part gamma indicator label design, Mercian Labels and Riverside Medical have worked together on a wide variety of designs and constructions incorporating gamma indicator strips, improving efficiency in manufacturing processes and satisfying regulatory requirements.”

Frank Morgan – Riverside Medical – 25th September 2018

“Steris has received excellent service – Gamma Stripe labels were printed and delivered at short notice due to stock shortage which enabled us to continue with production for our customers.
A big thank you to everyone who made this happen!”

Andrea Hales – 11th April 2019