ISO/ASTM 51631 covers the preparation and use of semi-adiabatic calorimeters for measurement of absorbed doses in graphite, water or polystyrene when irradiated with electrons. The calorimeters are either transported by a conveyor past a scanned electron beam or are stationary in a broadened beam. It also covers the use of these calorimeters to calibrate dosimeter systems in electron beams intended for radiation processing applications.
This International Standard applies to electron beams in the energy range from 4 MeV to 12 MeV.
The absorbed dose range depends on the absorbing material and the irradiation and measurement conditions. The minimum dose is approximately 100 Gy and maximum dose is approximately 50 kGy.
The averaged absorbed dose rate range shall generally be greater than 10 Gy·s-1 , but depends on the same conditions as above.
The temperature range for use of these calorimeters depends on the thermal resistance of the materials and on the calibration range of the temperature sensor.