1132 / 1542
- put ionisation chamber in H
2
O in reference conditions
- irradiate with photon beam
reading M
Q
(Q = quality of your beam)
D
w,Q
= M
Q
∙N
D,w,Co
∙k
Q,Co
∙
k
i
k
Q,Co
: correction of N
D,w,Co
for use in quality Q instead of Co
(depends on chamber type and beam quality Q)
N
D,w,Co
: chamber calibration factor, delivered by standards
laboratory
(N
D,w,Co
specific for each individual chamber)
corrections for deviations from reference conditions
other than Q, e.g. temperature, air pressure, recombination, etc.
k
i
:
i
calculate dose to H
2
O in absence chamber:
How to measure absorbed dose in water: