Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Isopentane

Isopentane is a volatile liquid or gas with a pleasant odor.

CAS 78-78-4 C5H12 72.15 g/mol Danger

01 · Identification

What Isopentane is

Isopentane is a volatile liquid or gas with a pleasant odor. Its molecular formula is C5H12 and its molecular weight is 72.15 g/mol. It boils at 27.8 °C, melts at -160 °C.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 4th degree.

02 · Identifiers

Isopentane identifiers and molecular data

Isopentane CAS number and EC number

CAS number78-78-4
EC number201-142-8
Index number (CLP Annex VI)601-085-00-2

Isopentane molecular formula and molecular weight

Molecular formulaC5H12
Molecular weight72.15 g/mol
Chemical class Flammable agents - 4th degree

Other names for Isopentane

  • 2-methylbutane

03 · GHS classification

Isopentane hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Isopentane pictograms and signal word

Signal wordDanger

Isopentane hazard class and category

GHS hazard classes Isopentane falls into
Hazard class Category From code Pictogram
Flammable liquids GHS chapter 2.6 Category 1 H224 GHS02
Specific target organ toxicity - single exposure GHS chapter 3.8 Category 3 narcotic H336 GHS07
Aspiration hazard GHS chapter 3.10 Category 1 H304 GHS08
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 2 H411 GHS09

Isopentane hazard statements (H-codes)

Hazard statements assigned to Isopentane
CodeHazard statement
H224 Extremely flammable liquid and vapour.
H304 May be fatal if swallowed and enters airways.
H336 May cause drowsiness or dizziness.
H411 Toxic to aquatic life with long lasting effects.

Isopentane supplemental EU statements (EUH)

EU-specific statements assigned to Isopentane. They exist only in CLP and have no counterpart in UN GHS.
CodeStatement
EUH066 Repeated exposure may cause skin dryness or cracking.

This page lists only the codes assigned to Isopentane. 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 Isopentane

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 Isopentane 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

Isopentane precautionary statements

CLP Annex VI assigns 8 precautionary statements to Isopentane. 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.

Response

What to do once exposure, spillage or fire has already happened.

Storage

How the container has to be kept between uses.

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

Isopentane 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 изопентан 2-метилбутан
Spanish español Isopentano 2-metilbutano
Czech čeština isopentan 2-methylbutan
Danish dansk isopentan 2-methylbutan
German Deutsch Isopentan 2-Methylbutan
Estonian eesti isopentaan 2-metüülbutaan
Greek ελληνικά ισοπεντάνιο 2-μεθυλοβουτάνιο
English English isopentane 2-methylbutane
French français isopentane 2-méthylbutane
Croatian hrvatski izopentan 2-metilbutan
Italian italiano isopentano 2-metilbutano
Latvian latviešu izopentāns 2-metilbutāns
Lithuanian lietuvių izopentanas 2-metilbutanas
Hungarian magyar izopentán 2-metilbután
Maltese Malti isopentan 2-metilbutan
Dutch Nederlands isopentaan 2-methylbutaan
Polish polski izopentan 2-metylobutan
Portuguese português isopentano 2-metilbutano
Romanian română izopentan 2-metilbutan
Slovak slovenčina izopentán 2-metylbután
Slovenian slovenščina izopentan 2-metilbutan
Finnish suomi isopentaani 2-metyylibutaani
Swedish svenska isopentan 2-metylbutan

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

Isopentane GHS label elements

Everything CLP Annex VI fixes for Isopentane, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS02 Flame pictogramGHS08 Health hazard pictogramGHS07 Exclamation mark pictogramGHS09 Environment pictogram

Danger

Isopentane

  • Extremely flammable liquid and vapour.
  • May be fatal if swallowed and enters airways.
  • May cause drowsiness or dizziness.
  • Toxic to aquatic life with long lasting effects.
  • Repeated exposure may cause skin dryness or cracking.
  • 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.
  • Avoid release to the environment.
  • Collect spillage.
  • Store in a well-ventilated place.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Isopentane in the GHS label constructor →

07 · Health hazards

Isopentane health hazards and exposure limits

Isopentane hazard summary

CNS depression is observed in mice exposed for 5-60 minutes at concentrations of 90,000-120,000 ppm (9-12% by volume); Concentrations of 150,000-170,000 ppm are lethal for dogs. [HSDB] See n-Pentane.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

Isopentane occupational exposure limits

US occupational exposure limits reported for Isopentane. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL 1000.0 [ppm] Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
PEL 1000 ppm (2950 mg/m³) Occupational Safety and Health Administration (OSHA)
REL 120 ppm (350 mg/m³) Occupational Safety and Health Administration (OSHA)
REL 610 ppm (1800 mg/m³) [15 minutes] Occupational Safety and Health Administration (OSHA)
IDLH 1500 ppm (as n-Pentane) 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

Isopentane 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.

Isopentane boiling point

Property Value Conditions Source
Boiling point 27.83 °C (82.1 °F) HSDB
27.78 °C (82 °F) at 760 mmHg CAMEO
28 °C (82.4 °F) ICSC

Isopentane melting point

Property Value Conditions Source
Melting point -159.8 °C (-255.6 °F) HSDB
-159.89 °C (-255.8 °F) CAMEO
-160 °C (-256 °F) ICSC

Isopentane density

Property Value Conditions Source
Density 0.6201 g/cm³ HSDB
0.6 g/cm³ ICSC
0.62 g/cm³ at 20 °C CAMEO

Isopentane solubility

Property Value Conditions Source
Solubility Insoluble in water HSDB
In water, 48 mg/L at 25 °C at 25 °C HSDB
In water, 49.6 mg/L at 25 °C at 25 °C HSDB

Isopentane vapor pressure

Property Value Conditions Source
Vapor pressure 689 mmHg OSHA
595 mmHg at 21.1 °C DOE PAC
592.549 mmHg at 20 °C ICSC

Isopentane flash point

Property Value Conditions Source
Flash point -51 °C (-59.8 °F) HSDB
-56.67 °C (-70 °F) CAMEO

Isopentane autoignition temperature

Property Value Conditions Source
Autoignition temperature 420 °C (788 °F) HSDB
426.67 °C (800 °F) CAMEO

Isopentane lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) 1.4 % by volume HSDB

Isopentane upper explosive limit (UEL)

Property Value Conditions Source
Upper explosive limit (UEL) 7.6 % by volume HSDB

Isopentane vapor density

Property Value Conditions Source
Vapor density 2.48 (air = 1) HSDB
2.5 (air = 1) ICSC

Isopentane odor threshold

Property Value Conditions Source
Odor threshold Odor Threshold Low: 400.0 [ppm] Haz-Map
Odor threshold from ACGIH Haz-Map

Isopentane critical temperature and pressure

Property Value Conditions Source
Critical temperature and pressure 187.25 °C (369.1 °F) HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Fire and explosion

Isopentane 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.

Isopentane fire potential

Flammable liquid. A very dangerous fire and explosion hazard when exposed to heat, flame or oxidizers.

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

Isopentane storage and handling

Isopentane safe storage

Fireproof. Well closed. Separated from strong oxidants. Store in an area without drain or sewer access. Provision to contain effluent from fire extinguishing.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

Isopentane 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. Recommended storage temperature 2-8 °C Refrigerate before opening. Handle and open container with care.

Source: Hazardous Substances Data Bank (HSDB)

Isopentane incompatible materials

Incompatible materials: Oxidizing agents.

Source: Hazardous Substances Data Bank (HSDB)

Isopentane reactivity

ISOPENTANE is a fire and explosion hazard when in contact with oxidizing agents. (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Isopentane in the storage compatibility matrix →

11 · Questions

Isopentane — frequently asked questions

What is the CAS number of Isopentane?

The CAS number of Isopentane is 78-78-4. Its EC number is 201-142-8.

What is the chemical formula of Isopentane?

The molecular formula of Isopentane is C5H12 and its molecular weight is 72.15 g/mol.

What does a Isopentane label have to show?

Under CLP Annex VI the label for Isopentane carries the pictograms Flame, Health hazard, Exclamation mark and Environment and the signal word is Danger.

Is Isopentane flammable?

Yes. CLP Annex VI assigns Isopentane H224 — extremely flammable liquid and vapour. The flash point reported for it is -51 °C (-59.8 °F) (HSDB).

Is Isopentane a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Isopentane. 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 Isopentane?

The US occupational exposure limit reported for Isopentane is 1000.0 [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 Isopentane?

The boiling point reported for Isopentane is 27.83 °C (82.1 °F) (HSDB).

What is the melting point of Isopentane?

The melting point reported for Isopentane is -159.8 °C (-255.6 °F) (HSDB).

How should Isopentane be stored?

CLP Annex VI assigns Isopentane 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. Recommended storage temperature 2-8 °C Refrigerate before opening. Handle and open container with care. (Hazardous Substances Data Bank (HSDB))

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