Substance profile
Uranium
Uranium is a silver-white, malleable, ductile, lustrous solid.
01 · Identification
What Uranium is
Uranium is a silver-white, malleable, ductile, lustrous solid. Its molecular formula is U and its molecular weight is 238.029 g/mol. It boils at 4131 °C, melts at 1135 °C.
Under the GHS it carries the signal word Danger. It is classed as flammable agents - 3rd degree.
02 · Identifiers
Uranium identifiers and molecular data
Uranium CAS number and EC number
Uranium molecular formula and molecular weight
03 · GHS classification
Uranium hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Uranium pictograms and signal word
Uranium hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Acute toxicity - oral GHS chapter 3.1 | Category 1 or 2 | H300 | GHS06 |
| Acute toxicity - inhalation GHS chapter 3.1 | Category 1 or 2 | H330 | GHS06 |
| Specific target organ toxicity - repeated exposure GHS chapter 3.9 | Category 2 | H373 | GHS08 |
| Hazardous to the aquatic environment - chronic GHS chapter 4.1 | Category 4 | H413 | — |
Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.
Uranium hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H330 | Fatal if inhaled. |
| H300 | Fatal if swallowed. |
| H373 | May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H413 | May cause long lasting harmful effects to aquatic life. |
This page lists only the codes assigned to Uranium. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.
Safety Data Sheet
Getting an SDS for Uranium
A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Uranium issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.
04 · Precautionary statements
Uranium precautionary statements
CLP Annex VI assigns 10 precautionary statements to Uranium. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.
Prevention
What to do before and during handling so the hazard never happens.
Response
What to do once exposure, spillage or fire has already happened.
Disposal
What has to happen to the contents and the empty container.
Reading the notation. … is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.
05 · Names in the regulation
Uranium name in 23 EU languages
CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.
| Language | Name in CLP Annex VI Part 3 |
|---|---|
| Bulgarian български | уран |
| Spanish español | Uranio |
| Czech čeština | uran |
| Danish dansk | uran |
| German Deutsch | Uran |
| Estonian eesti | uraan |
| Greek ελληνικά | ουράνιο |
| English English | uranium |
| French français | uranium |
| Croatian hrvatski | uranij |
| Italian italiano | uranio |
| Latvian latviešu | urāns |
| Lithuanian lietuvių | uranas |
| Hungarian magyar | urán |
| Maltese Malti | uranju |
| Dutch Nederlands | uraan |
| Polish polski | uran |
| Portuguese português | urânio |
| Romanian română | uraniu |
| Slovak slovenčina | urán |
| Slovenian slovenščina | uran |
| Finnish suomi | uraani |
| Swedish svenska | uran |
All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.
06 · Label elements
Uranium GHS label elements
Everything CLP Annex VI fixes for Uranium, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Uranium
- Fatal if inhaled.
- Fatal if swallowed.
- May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
- May cause long lasting harmful effects to aquatic life.
- Do not breathe dust/fume/gas/mist/vapours/spray.
- Do not eat, drink or smoke when using this product.
- Use only outdoors or in a well-ventilated area.
- Avoid release to the environment.
- IF SWALLOWED:
- IF INHALED:
- Immediately call a POISON CENTER/doctor/…
- Get medical advice/attention if you feel unwell.
- Rinse mouth.
- Dispose of contents/container to …
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Uranium in the GHS label constructor →
07 · Health hazards
Uranium health hazards and exposure limits
Uranium hazard summary
Uranium is a common naturally occurring and radioactive substance. It is a normal part of rocks, soil, air, and water, and it occurs in nature in the form of minerals "" but never as a metal. Uranium metal is silver-colored with a gray surface and is nearly as strong as steel. Natural uranium is a mixture of three types or isotopes called U-234/234U, U-235/235U and U-238/238U. All three are the same chemical, but they have different radioactive properties.Typical concentrations in soil are a few parts per million ppm. Some rocks contain high enough mineral concentrations of uranium to be mined. The rocks are taken to a chemical plant where the uranium is taken out and made into uranium chemicals or metal. The remaining sand is called mill tailings. Tailings are rich in the chemicals and radioactive materials that were not removed, such as radium and thorium.One of the radioactive properties of uranium is half-life, or the time it takes for half of the isotope to give off its radiation and change into another substance. The half-lives are very long around 200,000 years for234U, 700 million years for235U, and 5 billion years for238U. This is why uranium still exists in nature and has not all decayed away.The isotope235U is useful as a fuel in powerplants and weapons. To make fuel, natural uranium is separated into two portions. The fuel portion has more235U than normal and is called enriched uranium. The leftover portion with less235U than normal is called depleted uranium, or DU. Natural, depleted, and enriched uranium are chemically identical. Du is the least radioactive and enriched uranium the most.
Source: Agency for Toxic Substances and Disease Registry (ATSDR)
Uranium carcinogenicity classification
An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.
Uranium occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | 0.05 [mg/m3], as U (sol. compds), 0.25 mg/m3, as U (insol. compds) | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| PEL | 0.25 mg/m³ | Occupational Safety and Health Administration (OSHA) |
| PEL | 0.05 mg/m³ | Occupational Safety and Health Administration (OSHA) |
| REL | 0.2 mg/m³ | Occupational Safety and Health Administration (OSHA) |
| REL | 0.6 mg/m³ | Occupational Safety and Health Administration (OSHA) |
| REL | 0.05 mg/m³ | Occupational Safety and Health Administration (OSHA) |
| IDLH | 10.0 [mg/m3], as U | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| IDLH | 10 mg/cu m; NIOSH considers uranium (insoluble compounds, as U) to be a potential occupational carcinogen. /Uranium (insoluble compounds, as U)/ | Hazardous Substances Data Bank (HSDB) |
| IDLH | 10 mg/m³ | Occupational Safety and Health Administration (OSHA) |
These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.
08 · Physical and chemical properties
Uranium properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
Uranium boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 4131 °C (7467.8 °F) | HSDB | |
| 3813 °C (6895 °F) | NIOSH | ||
| 4131 °C (7468 °F) | OSHA |
Uranium melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 1135 °C (2075 °F) | HSDB | |
| 1147 °C (2097 °F) | NIOSH |
Uranium density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 19.1 g/cm³ | HSDB | |
| 19.05 g/cm³ | metal | NIOSH | |
| 19.1 g/cm³ | at 25 °C | DOE PAC |
Uranium solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Insol in water, alkalis, alcohol; soluble in acids | HSDB | |
| Insoluble | NIOSH |
Uranium vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 0 mmHg | approx | NIOSH |
| 0 mmHg | at 20 °C | HSDB |
Uranium autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | 20 °C (68 °F) | cloud | HSDB |
Uranium lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | Minimum explosive concn 60 g/cu m | for dust | HSDB |
| A dust cloud of uranium metal dust may ignite explosively at ordinary temperatures. | HSDB | ||
| Uranium is pyrophoric ... | HSDB |
Uranium vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 19.05 (air = 1) | metal | OSHA |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Uranium fire and explosion behaviour
These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.
Uranium fire potential
A very dangerous fire hazard in the form of a solid or dust when exposed to heat or flame.
Source: Hazardous Substances Data Bank (HSDB)
Solubility
Rapidly soluble in aqueous HCl. Non-oxidizing acids, such as sulfuric, phosphoric and hydrofluoric /acid/, react only very slowly with uranium; nitric acid dissolves massive uranium at a moderate rate.
Source: HSDB
10 · Handling and storage
Uranium storage and handling
Uranium storage conditions
Finely divided uranium metal is highly reactive or pyrophoric, capable of igniting spontaneously. This type of material should be handled and stored in a manner that minimizes fire potential. Typically, machining chips are stored under water or machining oil in open storage containers so that any H2 generated does not accumulate.
Source: Hazardous Substances Data Bank (HSDB)
Uranium incompatible materials
Uranium reacts with incandescence with hot selenium or sulfur (boiling).
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check Uranium in the storage compatibility matrix →
11 · Questions
Uranium — frequently asked questions
What is the CAS number of Uranium?
The CAS number of Uranium is 7440-61-1. Its EC number is 231-170-6.
What is the chemical formula of Uranium?
The molecular formula of Uranium is U and its molecular weight is 238.029 g/mol.
What does a Uranium label have to show?
Under CLP Annex VI the label for Uranium carries the pictograms Skull and crossbones and Health hazard and the signal word is Danger.
Is Uranium flammable?
CLP Annex VI assigns Uranium no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.
Is Uranium a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Uranium. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health. IARC places it in Group 1: carcinogenic to humans.
What is the exposure limit for Uranium?
The US occupational exposure limit reported for Uranium is 0.05 [mg/m3], as U (sol. compds), 0.25 mg/m3, as U (insol. compds) (Haz-Map, Information on Hazardous Chemicals and Occupational Diseases). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.
What is the boiling point of Uranium?
The boiling point reported for Uranium is 4131 °C (7467.8 °F) (HSDB).
What is the melting point of Uranium?
The melting point reported for Uranium is 1135 °C (2075 °F) (HSDB).
How should Uranium be stored?
Finely divided uranium metal is highly reactive or pyrophoric, capable of igniting spontaneously. This type of material should be handled and stored in a manner that minimizes fire potential. Typically, machining chips are stored under water or machining oil in open storage containers so that any H2 generated does not accumulate. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Uranium
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