Harwell Gammachrome YR ™Dosimeters

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Harwell Gammachrome YR ™Dosimeters 2017-06-21T09:29:19+00:00

GammachromeGammachrome YR™ are made from radiation-sensitive poly-methylmethacrylate (pmma) in the form of optically transparent pieces individually sealed in laminate sachets. They darken when irradiated, and the radiation-induced darkening, accurately measurable by means of a spectrophotometer, is a function of the radiation dose absorbed.

Dose Range

Gammachrome YR™ has a functional dose range of 0.1 kGy to 3.0 kGy which makes it ideal for very low dose irradiation processes.

Material

The Gammachrome YR ™ is made from single batches of cast sheets of poly-methylmethacrylate (pmma).

Dimensionsgammachrome_curve_picture

Harwell Dosimeters then cut the sheets down into plaques of 30mm x 11mm with a thickness of 3mm (+/- 0.55mm).

Packaging

After 100% inspection the dosimeters are packaged into sealed sachets made of polyester/aluminium foil/polyester/polyethylene laminate, each sachet being labelled with a unique bar code.

Packed 1,000 per carton.

(Packing to defined AQL’s checked to BS6001 (ISO 2859-1), single normal inspection, level II.)

Measurement reproducibility

Coefficient of variation of specific absorbance measurements on sets of dosimeters for the batch, simultaneously irradiated together, in a gamma radiation field uniform within +/- 1%, is 3% over the entire calibrated range, 0.1 to 3 kGy at 530nm wavelength.

Calibration quality

Over the calibrated range, all mean specific absorbance data points thus obtained are within 3% of a fourth-order polynomial least-squares fit to the data.

Shelf-life

Expected five years from the date of release.

Traceability

Harwell calibration is traceable to the UK standard of absorbed dose at the National Physical Laboratory (NPL).