(IND) BARIUM - 133 (Ba-133)
• Never used in humans
• Industrial sealed source or medical sealed source
• Used in “Buster” gauges

(IND) CESIUM - 137 (Cs-137)
• Never left in humans, used for medical therapy
• Most common industrial radio-nuclide in sealed sources
• Found in sealed sources, rarely as a powder

(IND) COBALT - 57 (Co-57)
• Never used in humans in detectable quantities
• Medical sealed sources, vials or large discs
• Rarely used as liquids or powders or capsules for people

(IND) COBALT - 60 (Co-60)
• Used for medical treatment
• Never found in humans
• Medical and industrial sealed sources
• Rarely as powders or metal pellets (MED) GALLIUM - 67 (Ga-67)
• Used in humans for diagnostic imaging
• Can be detectable for 2 – 3 weeks after medical procedure

(MED) IODINE - 131 (I-131)
• Used in humans and cats for radiation therapy
• Should be concentrated in the neck or bladder
• Will be detectable for 3 – 4 weeks after procedure
• People can be quite radioactive, 2 – 3 mr/hr

(MED) INDIUM - 111 (In-111)
• Used in humans for diagnostic imaging
• Can be detectable for 4 – 7 days post procedure

(IND) IRIDIUM - 192 (Ir-192)
• Never used in humans
• Industrial and medical sealed sources
• Often shipped in depleted Uranium shielding
• Sources can cause serious burns - NEVER OPEN PACKAGES

(SNM) NEPTUNIUM - 237 (Np-237)
• Never found in humans
• Nuclear reactor produced material

(NAT) POTASSIUM - 40 (K-40)
• Naturally occurring in humans and some plants
• Should not be identifiable in humans
• Found in large volumes of mineral salts

(NAT) RADIUM - 226 (Ra-226)
• Used in the past for treatment of humans
• Never left in humans
• Used in older wrist watches, clocks dials of radios,
compasses, rocks Uranium ore etc.
• Original “glow in the dark” material
• Many people are in unknowing possession

(MED) TECHNETIUM - 99m (Tc-99m)
• Most commonly used radio-nuclide in humans
• People can be very radioactive, 2 – 5 mr/hr

(NAT) THORIUM - 232 (Th-232)
• Never used in humans
• Metal, powder, chemical compounds, rocks
• Camera lenses as optical coating
• High temperature metal alloys, welding rods

(MED) THALLIUM - 201 (T1-201)
• Used in humans for heart imaging
• Can be detectable for 2 – 3 weeks after medical procedure

(IND) URANIUM - 238 (U-238)
• Never used in humans
• Metal, powder, chemical compounds (e.g. Uranyl Nitrate)

(MED) XENON - 133 (Xe-133)
• A radioactive gas used in humans for lung diagnosis
• Should not be found in humans
• Small cylinders may be shipped under license

(SNM) SNM Special Nuclear Materials
(U-233, Pu-239, U-235)
• Never found in humans
• Metals, powders
• Used for nuclear fission weapons

Neutrons Detected
• This alarm means that a consistent
source of neutrons is present in the area
• The most likely source is an industrial Am-241/Be source
• The source must be found and verified
• Neutrons also come from the plutonium and uranium used to build nuclear weapons