Substance profile
Hydrogen peroxide
Hydrogen peroxide is a colorless liquid with a slightly sharp odor.
01 · Identification
What Hydrogen peroxide is
Hydrogen peroxide is a colorless liquid with a slightly sharp odor. Its molecular formula is H2O2 and its molecular weight is 34.015 g/mol. It boils at 150 °C, melts at -0.4 °C.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
02 · Identifiers
Hydrogen peroxide identifiers and molecular data
Hydrogen peroxide CAS number and EC number
Hydrogen peroxide molecular formula and molecular weight
Other names for Hydrogen peroxide
- peroxide
- H2O2
- Albone
- Albone 35
- Albone Ds
- Baquashock
- Dihydrogen Dioxide
- Hipox
- Hybrite
- Hydrogen Dioxide
- Hydrogen Peroxide (35% To 52% By Weight)
- Hydrogen Peroxide (Conc.> 52%)
- Hydrogen Peroxide Solution (30%)
- Hydroperoxide
- hydrogen peroxide solution ...%
03 · GHS classification
Hydrogen peroxide hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Hydrogen peroxide pictograms and signal word
Hydrogen peroxide hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Oxidising liquids or Oxidising solids | Category 1 | H271 | GHS03 |
| Acute toxicity - oral GHS chapter 3.1 | Category 4 | H302 | GHS07 |
| Acute toxicity - inhalation GHS chapter 3.1 | Category 4 | H332 | GHS07 |
| Skin corrosion/irritation GHS chapter 3.2 | Category 1A or 1B or 1C | H314 | GHS05 |
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.
Hydrogen peroxide hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H271 | May cause fire or explosion; strong oxidiser. |
| H332 | Harmful if inhaled. |
| H302 | Harmful if swallowed. |
| H314 | Causes severe skin burns and eye damage. |
This page lists only the codes assigned to Hydrogen peroxide. 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 Hydrogen peroxide
Our own Hydrogen peroxide safety data sheet walks through all sixteen sections of the published data. What it is not is the document an inspector asks for: an SDS is issued for a product by its supplier, so the sheet covering the grade actually standing in your store exists only in that supplier’s version. Collecting those and keeping them current as suppliers revise them is a separate job.
04 · Precautionary statements
Hydrogen peroxide precautionary statements
CLP Annex VI assigns 10 precautionary statements to Hydrogen peroxide. 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
Hydrogen peroxide 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 | разтвор на водороден пероксид…% |
| Spanish español | Solución de peróxido de hidrógeno al … % |
| Czech čeština | peroxid vodíku … % |
| Danish dansk | hydrogenperoxidopløsning … % |
| German Deutsch | Wasserstoffperoxid-Lösung … % |
| Estonian eesti | vesinikperoksiidi lahus … % |
| Greek ελληνικά | διάλυμα υπεροξειδίου του υδρογόνου … % |
| English English | hydrogen peroxide solution… % |
| French français | péroxyde d'hydrogène, solution à …% |
| Croatian hrvatski | otopina vodikovog peroksida … % |
| Italian italiano | perossido di idrogeno soluzione …% |
| Latvian latviešu | ūdeņraža peroksīda šķīdums … % |
| Lithuanian lietuvių | … % vandenilio peroksido tirpalas |
| Hungarian magyar | hidrogén-peroxid oldat …% |
| Maltese Malti | soluzzjoni tal-perossidu tal-idroġenu …% |
| Dutch Nederlands | waterstofperoxide in oplossing … % |
| Polish polski | nadtlenek wodoru, roztwór … % |
| Portuguese português | peróxido de hidrogénio em solução a ... % |
| Romanian română | peroxid de hydrogen, soluție…% |
| Slovak slovenčina | peroxid vodíka, roztok … % |
| Slovenian slovenščina | raztopina vodikovega peroksida ... % |
| Finnish suomi | vetyperoksidiliuos … % |
| Swedish svenska | väteperoxidlösning… % |
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
Hydrogen peroxide GHS label elements
Everything CLP Annex VI fixes for Hydrogen peroxide, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Hydrogen peroxide
- May cause fire or explosion; strong oxidiser.
- Harmful if inhaled.
- Harmful if swallowed.
- Causes severe skin burns and eye damage.
- 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.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF INHALED:
- Immediately call a POISON CENTER/doctor/…
- Call a POISON CENTER/doctor/… if you feel unwell.
- Rinse mouth.
- Do NOT induce vomiting.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Hydrogen peroxide in the GHS label constructor →
07 · Health hazards
Hydrogen peroxide health hazards and exposure limits
Hydrogen peroxide hazard summary
Hydrogen peroxide is a colorless liquid at room temperature with a bitter taste. Small amounts of gaseous hydrogen peroxide occur naturally in the air. Hydrogen peroxide is unstable, decomposing readily to oxygen and water with release of heat. Although nonflammable, it is a powerful oxidizing agent that can cause spontaneous combustion when it comes in contact with organic material. Hydrogen peroxide is found in many households at low concentrations (3-9%) for medicinal applications and as a clothes and hair bleach. In industry, hydrogen peroxide in higher concentrations is used as a bleach for textiles and paper, as a component of rocket fuels, and for producing foam rubber and organic chemicals.
Source: Agency for Toxic Substances and Disease Registry (ATSDR)
Hydrogen peroxide carcinogenicity classification
Evaluation: There is inadequate evidence in humans for the carcinogenicity of hydrogen peroxide. There is limited evidence in experimental animals for the carcinogenicity of hydrogen peroxide. Overall evaluation: Hydrogen peroxide is not classifiable as to its carcinogenicity to humans (Group 3).
Source: Hazardous Substances Data Bank (HSDB)
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.
Hydrogen peroxide occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | 1.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| PEL | 1 ppm (1.4 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| PEL | TWA 1 ppm (1.4 mg/m3) | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | 1 ppm (1.4 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | TWA 1 ppm (1.4 mg/m3) | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | 75 ppm [From NPG: Hydrogen peroxide] (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 75 ppm (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 75.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
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
Hydrogen peroxide 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.
Hydrogen peroxide boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 150.2 °C (302.4 °F) | HSDB | |
| 141.11 °C (286 °F) | NIOSH | ||
| 150.22 °C (302.4 °F) | at 760 mmHg | CAMEO |
Hydrogen peroxide melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | -0.43 °C (31.2 °F) | HSDB | |
| -11.11 °C (12 °F) | NIOSH | ||
| -0.39 °C (31.3 °F) | CAMEO |
Hydrogen peroxide density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.44 g/cm³ | HSDB | |
| 1.71 g/cm³ | HSDB | ||
| 1 g/cm³ | HSDB |
Hydrogen peroxide solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Very soluble in water | HSDB | |
| In water, 1X10+6 mgL at 25 °C | at 25 °C | HSDB | |
| Soluble in ether; insoluble in petroleum ether. Decomposed into water and oxygen by many organic solvents. | decomposes | HSDB |
Hydrogen peroxide vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 1.5001 mmHg | at 20 °C | ICSC |
| 1.97 mmHg | at 25 °C | HSDB | |
| 1 mmHg | at 15.3 °C | HSDB |
Hydrogen peroxide autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | Not flammable. (USCG, 1999) | CAMEO |
Hydrogen peroxide vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 1.02 (air = 1) | CAMEO | |
| 1 (air = 1) | ICSC |
Hydrogen peroxide critical temperature and pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Critical temperature and pressure | 457 °C (854.6 °F) | HSDB |
Hydrogen peroxide corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | Corrosive | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Hydrogen peroxide 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.
Hydrogen peroxide fire potential
A dangerous fire hazard by chemical reaction with flammable materials. Hydrogen peroxide is a powerful oxidizer, particularly in the concentrated state. It is important to keep containers covered because the contents of uncovered containers are much more prone to react with flammable vapors, gases, etc.; and, if uncovered, the water from a hydrogen peroxide solution can evaporate, concentrating the material and thus increasing the fire hazard.
Source: Hazardous Substances Data Bank (HSDB)
Fire and explosion
Although pure hydrogen peroxide solutions are not usually explosive at atmospheric pressure, equilibrium vapor concentrations of hydrogen peroxide above 26 mol per cent (40 weight per cent) become explosive in a temperature range below the boiling point of the liquid.
Source: HSDB
A severe explosion hazard when highly concentrated or when pure hydrogen peroxide is exposed to: heat, mechanical impact, or detonation of a blasting cap, or is caused to decompose catalytically by metals (in order of decreasing effectiveness: osmium; palladium; platinum; iridium; gold; silver; manganese; cobalt; copper; lead).
Source: HSDB
Explodes on contact with alcohols + sulfuric acid; acetal + acetic acid + heat; acetic acid + n-heterocycles (above 50 °C); 2-amino-4-methyloxazole + iron(II) catalyst; aromatic hydrocarbons + trifluoroacetic acid; azeliac acid + sulfuric acid (above 45 °C); benzenesulfonic anhydride; tert-butanol + sulfuric acid; carboxylic acids; 3,5-dimethyl-3-hexanol + sulfuric acid; diphenyl diselenide (above 53 °C); 2-ethoxyethanol + polyacrylamide gel + toluene + heat; gadolinium hydroxide (above 80 °C); gallium + hydrochloric acid; hydrogen + palladium catalysts (has caused major industrial explosions); iron(II) sulfate + 2-methylpyridine + sulfuric acid; iron(II) sulfate + nitric acid + sodium carboxymethylcellulose (when evaporated); nitric acid + ketones (e.g., 2-butanone, 3-pentanone, cyclopentanone, cyclohexanone, 3-methylcyclohexanone), trioxane (sensitive to heat, shock, or on contact with lead), methanol + tert-amines + platinum catalysts; nitric acid + soils; nitrogenous bases (e.g., ammonia, hydrazine hydrate, 1,1-dimethylhydrazine); organic compounds (e.g., glycerol, acetic acid, ethanol, aniline, quinoline, 2-phenyl-1,1-dimethylethanol, cellulose, charcoal); organic materials + sulfuric acid (especially if confined); water + oxygenated compounds (e.g., acetaldehyde, acetic acid, acetone, ethanol, formaldehyde, formic acid, methanol, 2-propanol, propionaldehyde); sulfuric acid (during evaporation); tetrahydrothiophene; vinyl acetate; alcohols + tin chloride; phosphorus pentoxide; phosphorous; nitric acid; stibnite; arsenic trisulfide; chlorine + potassium hydroxide + chlorosulfonic acid; copper sulfide; iron(II) sulfide; formic acid + organic matter; hydrogen selenide; hydrazine; lead dioxide; lead monoxide; lead(II) sulfide; manganese dioxide; mercuric oxide; mercury(I) oxide; molybdenum disulfide; organic matter, (2-methyl-1-phenyl-2-propanol + sulfuric acid); potassium permanganate; sodium iodate; thiodiglycol; uns-dimethyl hydrazine; iron(II) sulfate + 2-methylpyridine + sulfuric acid; mercuric oxide + nitric acid.
Source: HSDB
10 · Handling and storage
Hydrogen peroxide storage and handling
Hydrogen peroxide reactive group
CAMEO Chemicals places Hydrogen peroxide in the reactive groups Oxidizing Agents, Strong, Water and Aqueous Solutions. Compatibility with other chemicals is worked out from the group, not from the individual substance — which is why two substances you have never seen react can still be flagged as a pair that must be separated.
A reactive group is a CAMEO Chemicals (US NOAA) grouping, not a GHS hazard class: it has no code, no category and no legal force. It is what the storage compatibility matrix on this site computes from.
Hydrogen peroxide safe storage
Store in an area without drain or sewer access. Separated from food and feedstuffs. See Chemical Dangers. Cool. Keep in the dark. Store in vented containers. Store only if stabilized.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Hydrogen peroxide 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. /Hydrogen peroxide solution (>/= 30% to <50%)/
Source: Hazardous Substances Data Bank (HSDB)
Hydrogen peroxide incompatible materials
Incompatible materials: Zinc, powdered metals, iron, copper, nickel, brass, iron and iron salts. /Hydrogen peroxide solution (>/= 30% to <50%)/
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check Hydrogen peroxide in the storage compatibility matrix →
11 · Transport
Hydrogen peroxide UN number and transport classification
Transport classification is a separate system from the GHS classification above. It decides how a package is marked and how a load may be carried; it does not follow from the workplace label, and the workplace label does not follow from it. The entries below are linked by CAS number, never by name.
The same CAS number is shipped under more than one UN number. Which entry applies follows from the form and the concentration of the consignment — read the proper shipping name, not the CAS.
Hydrogen peroxide under UN 2014 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| HYDROGEN PEROXIDE, AQUEOUS SOLUTION with not less than 20 % but not more than 60 % hydrogen peroxide (stabilized as necessary) | 5.1 | OC1 | II | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 5.1 is “Oxidizing substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Hydrogen peroxide, aqueous solutions with more than 40 percent but not more than 60 percent hydrogen peroxide (stabilized as necessary) | 5.1 | II | |
| Hydrogen peroxide, aqueous solutions with not less than 20 percent but not more than 40 percent hydrogen peroxide (stabilized as necessary) | 5.1 | II | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 5.1 is “Oxidizer” (49 CFR 173.2).
Hydrogen peroxide under UN 2015 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| HYDROGEN PEROXIDE, STABILIZED or HYDROGEN PEROXIDE, AQUEOUS SOLUTION, STABILIZED with more than 70 % hydrogen peroxide | 5.1 | OC1 | I | |
| HYDROGEN PEROXIDE, AQUEOUS SOLUTION, STABILIZED with more than 60 % hydrogen peroxide and not more than 70 % hydrogen peroxide | 5.1 | OC1 | I | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 5.1 is “Oxidizing substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Hydrogen peroxide, stabilized or Hydrogen peroxide aqueous solutions, stabilized with more than 60 percent hydrogen peroxide | 5.1 | I | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 5.1 is “Oxidizer” (49 CFR 173.2).
Hydrogen peroxide under UN 2984 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| HYDROGEN PEROXIDE, AQUEOUS SOLUTION with not less than 8 % but less than 20 % hydrogen peroxide (stabilized as necessary) | 5.1 | O1 | III | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 5.1 is “Oxidizing substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Hydrogen, peroxide, aqueous solutions with not less than 8 percent but less than 20 percent hydrogen peroxide (stabilized as necessary) | 5.1 | III | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 5.1 is “Oxidizer” (49 CFR 173.2).
12 · Questions
Hydrogen peroxide — frequently asked questions
What is the CAS number of Hydrogen peroxide?
The CAS number of Hydrogen peroxide is 7722-84-1. Its EC number is 231-765-0.
What is the chemical formula of Hydrogen peroxide?
The molecular formula of Hydrogen peroxide is H2O2 and its molecular weight is 34.015 g/mol.
What does a Hydrogen peroxide label have to show?
Under CLP Annex VI the label for Hydrogen peroxide carries the pictograms Flame over circle, Corrosion and Exclamation mark and the signal word is Danger.
Is Hydrogen peroxide flammable?
CLP Annex VI assigns Hydrogen peroxide 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 Hydrogen peroxide a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Hydrogen peroxide. 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 Hydrogen peroxide?
The US occupational exposure limit reported for Hydrogen peroxide is 1.0 [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 Hydrogen peroxide?
The boiling point reported for Hydrogen peroxide is 150.2 °C (302.4 °F) (HSDB).
What is the melting point of Hydrogen peroxide?
The melting point reported for Hydrogen peroxide is -0.43 °C (31.2 °F) (HSDB).
How should Hydrogen peroxide be stored?
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. /Hydrogen peroxide solution (>/= 30% to <50%)/ (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Hydrogen peroxide
Keep going: substances starting with H, or search the whole database by name, CAS number, pictogram or signal word.
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