Brilliant white metal; body-centered cubic structure.
In physical research, in radiography of metals because the penetration of gamma rays is more pronounced than that of x-rays, as source of radon.
Registry Numbers and Inventories.
Melting point, °C
Boiling point, °C
Solubility in water
Hazards and Protection.
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protective screens made from lead or concrete should be provided to reduce emissions of gamma-radiation. The thickness of the screen will depend on the level of radiation emitted. Remote manipulation devices should be employed wherever possible.
Use NIOSH/MSHA approved respirator appropriate for exposure of concern.
Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
Blackens on exposure to air; undergoes spontaneous disintegration with formation of radon.
Strong oxidizing agents.
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use agent most appropriate to extinguish fire.
Supralethal radiation doses may result in headache, acute brain syndrome, alterations in mental status including coma, and (rarely) seizures within minutes of exposure. Prenatal ionizing radiation exposure may cause congenital anomalies, mental retardation, and an increased incidence of seizures.
Gastrointestinal syndrome (nausea/vomiting) commonly occurs after doses of 9 to 20 gy and may occur following doses as low as 5 gy. Initial vomiting is followed by persistent diarrhea, which may be bloody.
Pulmonary radiation injury may result in radiation pneumonitis and radiation pulmonary fibrosis.
Thermonuclear burns may occur. If erythema is produced by a penetrating radiation, serious systemic injury is certain.
Seek medical attention. If individual is drowsy or unconscious, do not give anything by mouth; place individual on the left side with the head down. Contact a physician, medical facility, or poison control center for advice about whether to induce vomiting. If possible, do not leave individual unattended.
Monitoring exposed patients for contamination and decontamination procedures should be started. All personnel involved in handling patients should wear disposable protective clothing. The patient should be completely undressed and given a soap and water bath or shower (if the patient's condition permits and if the facility exists). Acute inhalation of radionuclides presents some difficult problems.
Remove contaminated clothing. Wash exposed area with soap and water. If symptoms persist, seek medical attention. Launder clothing before reuse.
If symptoms develop, immediately move individual away from exposure and into fresh air. Flush eyes gently with water for at least 15 minutes while holding eyelids apart; seek immediate medical attention.