Substance profile
2-methylpropan-2-ol
2-methylpropan-2-ol is a colorless liquid, which forms rhombic crystals melting at 25 to 25.5 °C with a camphor-like odor.
01 · Identification
What 2-methylpropan-2-ol is
2-methylpropan-2-ol is a colorless liquid, which forms rhombic crystals melting at 25 to 25.5 °C with a camphor-like odor. Its molecular formula is C4H10O and its molecular weight is 74.12 g/mol. It boils at 82.3 °C, melts at 25.8 °C.
Under the GHS it carries the signal word Danger. It is classed as flammable agents - 3rd degree.
02 · Identifiers
2-methylpropan-2-ol identifiers and molecular data
2-methylpropan-2-ol CAS number and EC number
2-methylpropan-2-ol molecular formula and molecular weight
Other names for 2-methylpropan-2-ol
- tert-butyl alcohol
03 · GHS classification
2-methylpropan-2-ol hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
2-methylpropan-2-ol pictograms and signal word
2-methylpropan-2-ol hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Flammable liquids GHS chapter 2.6 | Category 2 | H225 | GHS02 |
| Acute toxicity - inhalation GHS chapter 3.1 | Category 4 | H332 | GHS07 |
| Serious eye damage/eye irritation GHS chapter 3.3 | Category 2A | H319 | GHS07 |
| Specific target organ toxicity - single exposure GHS chapter 3.8 | Category 3 | H335 | GHS07 |
2-methylpropan-2-ol hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H225 | Highly flammable liquid and vapour. |
| H332 | Harmful if inhaled. |
| H335 | May cause respiratory irritation. |
| H319 | Causes serious eye irritation. |
This page lists only the codes assigned to 2-methylpropan-2-ol. 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 2-methylpropan-2-ol
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 2-methylpropan-2-ol 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
2-methylpropan-2-ol precautionary statements
CLP Annex VI assigns 15 precautionary statements to 2-methylpropan-2-ol. 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
2-methylpropan-2-ol 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 | 2-метилпропан-2-ол трет -бутилов алкохол |
| Spanish español | 2-Metilpropan-2-ol alcohol terc -butílico |
| Czech čeština | 2-methylpropan-2-ol terc -butylalkohol |
| Danish dansk | 2-methylpropan-2-ol tert -butylalkohol |
| German Deutsch | 2-Methylpropan-2-ol tert -Butylalkoholtert-Butanol |
| Estonian eesti | 2-metüülpropaan-2-ool tert -butüülalkohol |
| Greek ελληνικά | 2-μεθυλοπροπαν-2-όλη tert -βουτυλική αλκοόλη |
| English English | 2-methylpropan-2-ol tert -butyl alcohol |
| French français | 2-méthylpropan-2-ol alcool tert -butylique |
| Croatian hrvatski | 2-metil-propan-2-ol tert -butil-alkohol |
| Italian italiano | 2-metilpropan-2-olo alcool terz -butilico |
| Latvian latviešu | 2-metilpropān-2-ols terc -butilspirts |
| Lithuanian lietuvių | 2-metilpropan-2-olis tret -butilo alkoholis |
| Hungarian magyar | 2-metilpropán-2-ol terc -butil-alkohol |
| Maltese Malti | 2-metilpropan-2-ol alkoħol terz -butil |
| Dutch Nederlands | 2-methylpropaan-2-ol tert -butylalcohol |
| Polish polski | 2-metylopropan-2-ol alkohol tert -butylowy |
| Portuguese português | 2-metilpropan-2-ol álcool terc -butílico |
| Romanian română | 2-metilpropan-2-ol alcool terț -butilic |
| Slovak slovenčina | 2-metylpropán-2-ol terc -butylalkohol |
| Slovenian slovenščina | 2-metilpropan-2-ol terc -butil alkohol |
| Finnish suomi | 2-metyylipropan-2-oli tert -butyylialkoholi |
| Swedish svenska | 2-metylpropan-2-ol tert -butylalkohol |
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
2-methylpropan-2-ol GHS label elements
Everything CLP Annex VI fixes for 2-methylpropan-2-ol, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
2-methylpropan-2-ol
- Highly flammable liquid and vapour.
- Harmful if inhaled.
- May cause respiratory irritation.
- Causes serious eye irritation.
- Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
- Keep container tightly closed.
- Use explosion-proof [electrical/ventilating/lighting/…] equipment.
- Use only non-sparking tools.
- Do not breathe dust/fume/gas/mist/vapours/spray.
- Wash … thoroughly after handling.
- Use only outdoors or in a well-ventilated area.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF INHALED:
- IF IN EYES:
- Call a POISON CENTER/doctor/… if you feel unwell.
- Get medical advice/attention.
- If eye irritation persists:
- Remove contact lenses, if present and easy to do. Continue rinsing.
- Store in a well-ventilated place.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open 2-methylpropan-2-ol in the GHS label constructor →
07 · Health hazards
2-methylpropan-2-ol health hazards and exposure limits
2-methylpropan-2-ol hazard summary
Animals in feeding studies develop alcohol intoxication; [ACGIH] A skin, eye, and respiratory tract irritant; Inhalation of high concentrations can cause CNS depression; [ICSC]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
2-methylpropan-2-ol carcinogenicity classification
Under the conditions of these 2-year drinking water studies, there was some evidence of carcinogenic activity of t -butyl alcohol in male F344/N rats based on increased incidences of renal tubule adenoma or carcinoma (combined). There was no evidence of carcinogenic activity in female F344/N rats receiving 2.5, 5, or 10 mg/mL t -butyl alcohol. There was equivocal evidence of carcinogenic activity of t -butyl alcohol in male B6C3F1 mice based on the marginally increased incidences of follicular cell adenoma or carcinoma (combined) of the thyroid gland. There was some evidence of carcinogenic activity of t -butyl alcohol in female B6C3F1 mice based on increased incidences of follicular cell adenoma of the thyroid gland.
Source: US National Toxicology Program · TR-436: Toxicology and Carcinogenesis Studies of t-Butyl Alcohol (CASRN 75-65-0) in F344/N Rats and B6C3F1 Mice (Drinking Water Studies) (1995 )
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.
2-methylpropan-2-ol occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | 100.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| PEL | 100 ppm (300 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| PEL | TWA 100 ppm (300 mg/m3) See Appendix G | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | 100 ppm (300 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | 150 ppm (450 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | TWA 100 ppm (300 mg/m3) ST 150 ppm (450 mg/m3) | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | 1600 ppm (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 1600.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| IDLH | 1600 ppm | 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
2-methylpropan-2-ol 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.
2-methylpropan-2-ol boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 82.3 °C (180.1 °F) | HSDB | |
| 82.22 °C (180 °F) | NIOSH | ||
| 82.22 °C (180 °F) | at 760 mmHg | CAMEO |
2-methylpropan-2-ol melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 25.81 °C (78.5 °F) | HSDB | |
| 25.56 °C (78 °F) | NIOSH | ||
| 25.5 °C (77.9 °F) | CAMEO |
2-methylpropan-2-ol density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 0.79 g/cm³ | Solid | NIOSH |
| 0.7886 g/cm³ | at 20 °C | HSDB | |
| 0.78 g/cm³ | at 26 °C | CAMEO |
2-methylpropan-2-ol solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Miscible with ethanol, ethyl ether; soluble in chloroform | HSDB | |
| Miscible | NIOSH | ||
| In water, 1X10+6 mg/L at 25 °C | at 25 °C, Miscible | HSDB |
2-methylpropan-2-ol vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 31 mmHg | at 20 °C | CAMEO |
| 40.7 mmHg | at 25 °C | HSDB | |
| 42 mmHg | at 25 °C | NIOSH |
2-methylpropan-2-ol flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | 11.11 °C (52 °F) | HSDB |
2-methylpropan-2-ol autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | 477.78 °C (892 °F) | HSDB | |
| 480 °C (896 °F) | CAMEO | ||
| 470 °C (878 °F) | ICSC |
2-methylpropan-2-ol lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | 2.4 % by volume | HSDB | |
| 2.35 % by volume | HSDB |
2-methylpropan-2-ol upper explosive limit (UEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Upper explosive limit (UEL) | 8 % by volume | HSDB |
2-methylpropan-2-ol vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 2.55 (air = 1) | HSDB | |
| 2.6 (air = 1) | ICSC |
2-methylpropan-2-ol odor threshold
| Property | Value | Conditions | Source |
|---|---|---|---|
| Odor threshold | Odor threshold 219 mg/cu m (odor low) 219 mg/cu m (odor high) | HSDB | |
| Odor Threshold Low: 3.3 [ppm] | Haz-Map | ||
| Odor Threshold High: 957.0 [ppm] | Haz-Map |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
2-methylpropan-2-ol 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.
2-methylpropan-2-ol fire potential
Highly flammable liquid and vapor.
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
2-methylpropan-2-ol storage and handling
2-methylpropan-2-ol safe storage
Fireproof. Separated from strong oxidants and strong acids.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
2-methylpropan-2-ol storage conditions
Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage.
Source: Hazardous Substances Data Bank (HSDB)
2-methylpropan-2-ol incompatible materials
Incompatible with oxidizing materials, H2O2.
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check 2-methylpropan-2-ol in the storage compatibility matrix →
11 · Questions
2-methylpropan-2-ol — frequently asked questions
What is the CAS number of 2-methylpropan-2-ol?
The CAS number of 2-methylpropan-2-ol is 75-65-0. Its EC number is 200-889-7.
What is the chemical formula of 2-methylpropan-2-ol?
The molecular formula of 2-methylpropan-2-ol is C4H10O and its molecular weight is 74.12 g/mol.
What does a 2-methylpropan-2-ol label have to show?
Under CLP Annex VI the label for 2-methylpropan-2-ol carries the pictograms Flame and Exclamation mark and the signal word is Danger.
Is 2-methylpropan-2-ol flammable?
Yes. CLP Annex VI assigns 2-methylpropan-2-ol H225 — highly flammable liquid and vapour. The flash point reported for it is 11.11 °C (52 °F) (HSDB).
Is 2-methylpropan-2-ol a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for 2-methylpropan-2-ol. 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 3: not classifiable as to its carcinogenicity to humans.
What is the exposure limit for 2-methylpropan-2-ol?
The US occupational exposure limit reported for 2-methylpropan-2-ol is 100.0 [ppm] (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 2-methylpropan-2-ol?
The boiling point reported for 2-methylpropan-2-ol is 82.3 °C (180.1 °F) (HSDB).
What is the melting point of 2-methylpropan-2-ol?
The melting point reported for 2-methylpropan-2-ol is 25.81 °C (78.5 °F) (HSDB).
How should 2-methylpropan-2-ol be stored?
CLP Annex VI assigns 2-methylpropan-2-ol the storage statement P403. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. (Hazardous Substances Data Bank (HSDB))
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