Table 1.

Cylindrical ionization chamber construction properties.

Ionization Chamber	PinPoint	IC10	Farmer‐type (NE2571)
Nominal sensitive volume	0.015 cm3	0.13 cm3	0.69 cm3
Sensitive volume length	5 mm	5.8 mm	24.1 mm
Inner diameter of outer electrode	2 mm	6 mms	6.3 mm
Wall material	PMMA $1.19\mathrm{g}/{\text{cm}}^3$, graphite $0.82\mathrm{g}/{\text{cm}}^3$	Shonka C552 $1.76\mathrm{g}/{\text{cm}}^3$	graphite $0.82\mathrm{g}/{\text{cm}}^3$
Wall thickness	PMMA 0.56 mm graphite 0.15 mm	0.4 mm	0.36 mm
Inner electrode material	Steel	Shonka C552	aluminum
Length of inner electrode	4.5 mm	3.3 mm	20.5 mm