We offer a variety replacement probes for our Radiation Alert® instruments.
SE International can help you find just the right probe for your application. Below are the specifications for the most common detectors that we offer.
Custom Probe Options Available. Tell us about your application and we can recommend the best probe options for your needs.
DetectorExternal Halogen-quenched, uncompensated Geiger Muller tube with a thin mica window, 1.4-2.0 mg/cm2 areal density. Effective diameter of window is 45 mm (1.75 in.). Radiation symbol on probe head label marks the center of the detector Which Detector Works With My Model of EXP?All Ranger EXP Models are RAP-RS2 Probes with BNC. For Previous Model SEI’s Radiation Alert Inspector EXPs:The RAP-RS1 fits the EXP Models (SN#s 27299 and lower) No longer available. |
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Anodized aluminum housing
RAP-RS1 Approx. 8.75 X 1 in. (222 X 25 mm) Dia.: 2.75 in. (70 mm)
RAP-RS2 Approx. 10.7 X 1 in. (272 X 25 mm) Dia : 2.75 in. (70 mm)
RAP-RS1: Amphenol-Tucal
RAP-RS2: BNC
Black foam grip
RAP-RS1: Approx. 11.5 oz. (328 g) w/o cable
RAP-RS2: Approx. 9.6 oz. (272 g) w/o cable

| Indicated Use | Low-level, wide-energy gamma detection | |
|---|---|---|
| Detector Type | NaI(Tl) scintillator, 2.5 cm (1 in) dia. x 2.5 cm (1 in) thick | |
| Efficiency (4π) | 125I | 7% |
| 57Co | 10% | |
| 137Cs | 3% | |
| 60Co | 3% | |
| Energy Range | 20 keV to 1.5 MeV | |
|
Sensitivity |
Cs-137 Sensitivity at 1 mR/h (662 keV) |
|
| Photomultiplier Tube | 2.86 cm (1.123 in) diameter, magnetically shielded | |
| Operating Voltage | 500 to 1200 V | |
| Temperature Range | -15 to 50 °C (5 to 122 °F) May be certified for -40 to 65 °C (-40 to 150 °F) |
|
| Connector | Series "C" | |
| Construction | Aluminum with beige powder coat | |
| Size (D x L) | 5.1 x 18.5 cm (2 x 7.3 in) | |
| Weight | 0.5 kg (1 lb) | |

| Indicated Use | Low-level, wide-energy gamma detection | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Detector Type | NaI(Tl) scintillator, 2.5 cm (1 in) dia. x 2.5 cm (1 in) thick | |||||||||
| Efficiency (4π) |
|
|||||||||
| Energy Range | 30 keV to 3.0 MeV | |||||||||
|
Sensitivity |
Cs-137 Sensitivity at 1 mR/h (662 keV) |
|||||||||
| Photomultiplier Tube | 2.86 cm (1.123 in) diameter, magnetically shielded | |||||||||
| Operating Voltage | 500 to 1200 V | |||||||||
| Temperature Range | -15 to 50 °C (5 to 122 °F) May be certified for -40 to 65 °C (-40 to 150 °F) |
|||||||||
| Connector | Series "C" | |||||||||
| Construction | Aluminum with beige powder coat | |||||||||
| Size (D x L) | 6.6 x 27.9 cm (2.6 x 11 in.) | |||||||||
| Weight | 1.04 kg (2.3 lb) | |||||||||