Harwell Red 4034 Dosimeters

Red 4034 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

Red 4034 has a functional dose range of 5 kGy to 50 kGy which makes it idea for a wide range of irradiation processes.

Material

The 4034 Red is made from single batches of cast sheets of poly-methylmethacrylate (pmma)

Dimensions

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. With each sachet being labeled with a unique bar coded label.

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, simltaneously irradiated together, in a gamma radiation field uniform within +/- 1%, is 2% over the entire calibrated range, 5 to 50 kGy.

Calibration quality

Over the calibrated range, all mean specific absorbance data points thus obtained are within 2% of a fourth-order polynomial least-squares fit to the data.

Shelf-life

Ten years from the date of release.

Traceability

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