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Ordering Info


The IC-17 is a three terminal 1cc spherical ionization chamber. It is available with a wide range of different wall materials including tissue equivalent plastic, air equivalent plastic, graphite, magnesium, and polyethylene. These chambers are used for direct comparison of radiation source strengths, beam monitoring in accelerator facilities, and accurate measurement of absorbed dose at a prescribed experimental point. By using a pair with different wall materials, one hydrogenous and one non hydrogenous, it is possible to measure mixed fields and separate the gamma and neutron components.

The spherical detector is mounted on the end of a stem with the signal connections made through a terminal block. The block contains the BNC signal connector and the MHV high voltage connector. The stem effects are less than 1 x 10E-12A for a 1 x 10E4 R/h exposure with Co60. The effect may be minimized by using a + and – collecting voltage on the detector and averaging the readings.

Model Number Chamber Volume

Wall Material

Wall Thickness Wall Density
IC-17 1 CC Tissue Equivalent Plastic 0.200" 569 mg/cm2
IC-17A 1 CC Tissue Equivalent Plastic 0.050" 142 mg/cm2
IC-17G 2.5 CC Graphite 0.119" 543 mg/cm2
IC-17M 2.2 CC Magnesium 0.123" 543 mg/cm2
IC-17P 1 CC Conductive Polyethylene 0.200" 569 mg/cm2


Ionization Chamber: Spherical collecting volume; guarded three-terminal design; TE plastic, graphite, magnesium, or conductive polyethylene wall; collecting electrode same material as wall; mounted on a 10.5-inch (26.7 cm) long aluminum stem; built in gas flow provision is optional
Wall Materials: Tissue Equivalent Plastic, r =1.13 g/cm3; Graphite, high purity, r =1.80 g/cm3; magnesium, high purity, r =1 .74 g/cm3; polyethylene, -3% added carbon for conductivity, r =1.12 g/cm3
Signal Connector: BNC, mates with UG26OB/U or equivalent
Signal Output IC17A: 3.8 x 10E9 R/coul for air with Cs137
Leakage: Typically 5 x 10E-15 A when low noise coax is used (measured without collection voltage).
Collection Efficiency: 99% for 3x10E5 R/h @ 250V, 99% for 7x10E5 R/h @ 300V
Recommended Signal Cable: Low noise coaxial, e.g., MALCO 250-3834-0000
High Voltage Requirements: Positive or negative polarity, 250 to 500 V depending on source strength. Shell is at high voltage potential.
High Voltage Connector: MHV, mates with UG 932 A/U or equivalent; optionally SHV
High Voltage Cable: RG-59/U or equivalent
Overall Size and Weight: Length including connectors, 14.0 inches (35.7 cm); stem is 10.5 inches (26.7 cm) long; weight 94 grams
Calibration Furnished: R/coul at Cs137 with air and appropriate gas
Accessories: Supplied with wooden storage box


Ordering Information
See model numbers in table above. Add additional options below. All ionization chambers are supplied with storage box.
GF: with gas flow provision
-WH: with waterproof housing
-BC: with TE buildup cap (IC-17A Only)
Consult factory for other wall materials.

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Specifications subject to change without notice.
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