Substance profile
Diboron trioxide
Diboron trioxide is colorless, brittle, vitreous, semitransparent lumps or hard, white crystals and is odorless.
01 · Identification
What Diboron trioxide is
Diboron trioxide is colorless, brittle, vitreous, semitransparent lumps or hard, white crystals and is odorless. It boils at 1500 °C, melts at 450 °C.
Under the GHS it carries the signal word Danger.
02 · Identifiers
Diboron trioxide identifiers and molecular data
Diboron trioxide CAS number and EC number
03 · GHS classification
Diboron trioxide hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Diboron trioxide pictograms and signal word
Diboron trioxide hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H360FD | May damage fertility. May damage the unborn child. |
This page lists only the codes assigned to Diboron trioxide. 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 Diboron trioxide
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 Diboron trioxide 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
Diboron trioxide precautionary statements
CLP Annex VI assigns 4 precautionary statements to Diboron trioxide. 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.
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
Diboron trioxide 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 | диборен триоксид |
| Spanish español | Trióxido de diboro |
| Czech čeština | oxid boritý |
| Danish dansk | dibortrioxid |
| German Deutsch | Dibortrioxid |
| Estonian eesti | diboortrioksiid |
| Greek ελληνικά | τριοξείδιο του βορίου |
| English English | diboron trioxide |
| French français | trioxyde de dibore |
| Croatian hrvatski | diborov trioksid |
| Italian italiano | triossido di diboro |
| Latvian latviešu | dibora trioksīds |
| Lithuanian lietuvių | diboro trioksidas |
| Hungarian magyar | dibór-trioxid |
| Maltese Malti | triossidu tad-diboron |
| Dutch Nederlands | diboortrioxide |
| Polish polski | tritlenek diboru |
| Portuguese português | trióxido de diboro |
| Romanian română | trioxid de dibor |
| Slovak slovenčina | oxid boritý |
| Slovenian slovenščina | diborov trioksid |
| Finnish suomi | dibooritrioksidi |
| Swedish svenska | dibortrioxid |
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
Diboron trioxide GHS label elements
Everything CLP Annex VI fixes for Diboron trioxide, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Diboron trioxide
- May damage fertility. May damage the unborn child.
- Obtain special instructions before use.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF exposed or concerned:
- Get medical advice/attention.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Diboron trioxide in the GHS label constructor →
07 · Health hazards
Diboron trioxide health hazards and exposure limits
Diboron trioxide hazard summary
An eye and respiratory irritant; See Boric acid. Boron is a hepatotoxic agent. [Zimmerman, p. 4] A skin, eye, and respiratory tract irritant; [ICSC]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Diboron trioxide occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | 15.0 [mg/m3], total dust | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| PEL | 15 mg/m³ (total dust) | Occupational Safety and Health Administration (OSHA) |
| PEL | TWA 15 mg/m3 See Appendix G | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | 10 mg/m³ | Occupational Safety and Health Administration (OSHA) |
| REL | TWA 10 mg/m3 | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | 2000 mg/m3 (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 2000.0 [mg/m3] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| IDLH | 2000 mg/cu m | Hazardous Substances Data Bank (HSDB) |
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
Diboron trioxide 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.
Diboron trioxide boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 1500 °C (2732 °F) | crystal | HSDB |
| 1860 °C (3380 °F) | NIOSH | ||
| 1860 °C (3380 °F) | at 760 mmHg | CAMEO |
Diboron trioxide melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 450 °C (842 °F) | crystal | HSDB |
| 450 °C (842 °F) | NIOSH |
Diboron trioxide density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.8 g/cm³ | amorphous | HSDB |
| 2.46 g/cm³ | NIOSH |
Diboron trioxide solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Slowly soluble in 30 parts cold water; slowly soluble in 5 parts boiling water; soluble in alcohol, glycerol | HSDB | |
| Water solubility: 4.0% at 20 °C | at 20 °C | HSDB | |
| 2.77 g/100 g water at 20 °C. | at 20 °C | HSDB |
Diboron trioxide vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 0 mmHg | approx | NIOSH |
Diboron trioxide lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | Noncombustible Solid | NIOSH |
Diboron trioxide corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | Very corrosive to metals in the presence of oxygen | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Diboron trioxide 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.
Diboron trioxide fire potential
Noncombustible
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
Diboron trioxide storage and handling
Diboron trioxide safe storage
Dry. Well closed.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Diboron trioxide storage conditions
Dry.
Source: Hazardous Substances Data Bank (HSDB)
Diboron trioxide incompatible materials
Attacks metal in the presence of moist air.
Source: Hazardous Substances Data Bank (HSDB)
Diboron trioxide reactivity
BORON OXIDE is non-combustible. Of generally low chemical reactivity. Reacts exothermically but slowly with water to form boric acid, a weak acid. Reacts exothermically with strong bases. May react with strong reducing agents such as metal hydrides, metal alkyls to generate flammable or explosive gases. May react violently on contact with bromine pentafluoride. Corrosive to metals in the presence of air.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Diboron trioxide in the storage compatibility matrix →
11 · Questions
Diboron trioxide — frequently asked questions
What is the CAS number of Diboron trioxide?
The CAS number of Diboron trioxide is 1303-86-2. Its EC number is 215-125-8.
What does a Diboron trioxide label have to show?
Under CLP Annex VI the label for Diboron trioxide carries the pictogram Health hazard and the signal word is Danger.
Is Diboron trioxide flammable?
CLP Annex VI assigns Diboron trioxide 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 Diboron trioxide a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Diboron trioxide. 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.
What is the exposure limit for Diboron trioxide?
The US occupational exposure limit reported for Diboron trioxide is 15.0 [mg/m3], total dust (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 Diboron trioxide?
The boiling point reported for Diboron trioxide is 1500 °C (2732 °F), crystal (HSDB).
What is the melting point of Diboron trioxide?
The melting point reported for Diboron trioxide is 450 °C (842 °F), crystal (HSDB).
How should Diboron trioxide be stored?
Dry. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Diboron trioxide
Keep going: substances starting with D, or search the whole database by name, CAS number, pictogram or signal word.