Agent Name

Uranium hexafluoride

CAS Number

7783-81-5

Formula

F6-U

Major Category

Toxic Gases & Vapors

Synonyms

Uranium fluoride (UF6); Uranyl fluoride; Uranium hexafluoride, fissile (with more than 1% U-235) [UN2977]; Uranium hexafluoride, fissile excepted or non-fissile [UN2978] [ChemIDplus]

Category

Other Toxic Gases & Vapors

Description

Colorless to white crystals; [HSDB]

Sources/Uses

Used to manufacture fuel for nuclear power; [CAMEO] Uranium ore is produced from underground and open-pit mines. From the ores, uranium mills produce yellowcake, which is a complex mixture containing 80-96% uranium. The yellowcake is used to produce nuclear fuel. [PMID 14691274 ] In the nuclear fuel cycle, yellowcake is converted into uranium hexafluoride gas, which is fed through centrifuges repeatedly to separate isotopes until uranium is enriched. The low-level enriched uranium is used for nuclear fuel while the highly enriched can be used in nuclear weapons. [BBC News]

Comments

Sublimes at room temperature; Reacts with water releasing uranyl fluoride and hydrogen fluoride; [HSDB] Low-level radioactive; "Chemical hazard greatly exceeds radiation hazard." Reacts with water to generate hydrogen fluoride gas; [CAMEO] See "Uranium" and the linked occupational disease.

Exposure Assessment
BEI

Fluorides in urine = 2 mg/L prior to shift or 3 mg/L at end of shift; (Repeated measurements recommended.) Uranium in urine = 200 ug/L at end of shift;

Dangerous When Wet

Yes - A material that, by contact with water, is liable to become spontaneously flammable or to give off flammable or toxic gas at a rate greater than 1 L per kilogram of the material, per hour; [ERG 2004]

TLV (ACGIH)

0.2 mg/m3, as U (2.5 mg/m3, as F)

STEL (ACGIH)

0.6 mg/m3, as U

PEL (OSHA)

0.05 mg/m3, as U (sol), 0.25 mg/m3, as U (insol) [2.5 mg/m3, as F]

MAK

1 mg/m3, as F, inhalable fraction

IDLH (NIOSH)

10 mg/m3, as U

Vapor Pressure

115 mm Hg

Explanatory Notes

Melting point = 64.8 degrees C; [Merck Index, 9856] Soluble in chloroform; Decomposes in water; [ATSDR ToxProfiles]

Adverse Effects
Toxic Pneumonitis

Yes

Dermatotoxin

Skin Burns

Links to Other NLM Databases
Health Studies

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Toxicity Information

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Chemical Information

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Related Information in HazMap
Diseases

Occupational diseases associated with exposure to this agent:

Processes

Industrial Processes with risk of exposure: