Substance profile
Sodium hypochlorite
Sodium hypochlorite is a greenish yellow liquid with a disagreeable, sweetish odor.
01 · Identification
What Sodium hypochlorite is
Sodium hypochlorite is a greenish yellow liquid with a disagreeable, sweetish odor. Its molecular formula is ClNaO and its molecular weight is 74.44 g/mol. It boils at 111 °C, melts at 18 °C.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
02 · Identifiers
Sodium hypochlorite identifiers and molecular data
Sodium hypochlorite CAS number and EC number
Sodium hypochlorite molecular formula and molecular weight
Other names for Sodium hypochlorite
- bleach
- liquid chlorine
- NaOCl
- Hyclorite
- Javel Water
- Javelle Water
- Javex
- Klorocin
- Milton
- Neo-Cleaner
- Neoseptal Cl
- Parozone
- Purin B
- Sodium Hypochlorite (Naclo)
- Sodium Hypochlorite (Naocl)
- Antiformin
- B-K Liquid
- Chloros
- Clorox
- Deosan
- Hypure
- Hypure N
- sodium hypochlorite, solution ... % Cl active
03 · GHS classification
Sodium hypochlorite hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Sodium hypochlorite pictograms and signal word
Sodium hypochlorite hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Skin corrosion/irritation GHS chapter 3.2 | Category 1A or 1B or 1C | H314 | GHS05 |
| Serious eye damage/eye irritation GHS chapter 3.3 | Category 1 | H318 | GHS05 |
| Hazardous to the aquatic environment - acute GHS chapter 4.1 | Category 1 | H400 | GHS09 |
| Hazardous to the aquatic environment - chronic GHS chapter 4.1 | Category 1 | H410 | GHS09 |
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.
Sodium hypochlorite hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H314 | Causes severe skin burns and eye damage. |
| H318 | Causes serious eye damage. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic to aquatic life with long lasting effects. |
Sodium hypochlorite supplemental EU statements (EUH)
| Code | Statement |
|---|---|
| EUH031 | Contact with acids liberates toxic gas. |
This page lists only the codes assigned to Sodium hypochlorite. 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 Sodium hypochlorite
Our own Sodium hypochlorite 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
Sodium hypochlorite precautionary statements
CLP Annex VI assigns 10 precautionary statements to Sodium hypochlorite. 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
Sodium hypochlorite 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 | натриев хипохлорит, разтвор … % активен Cl |
| Spanish español | Hipoclorito de sodio, solución … % Cl activo |
| Czech čeština | chlornan sodný, roztok, obsah aktivního chloru … % |
| Danish dansk | natriumhypochloritopløsning … % aktiv chlor |
| German Deutsch | Natriumhypochloritlösung … % Cl aktiv |
| Estonian eesti | naatriumhüpokloriti lahus, … % aktiivset kloori |
| Greek ελληνικά | υποχλωριώδες νάτριο, διάλυμα … % ενεργό Cl |
| English English | sodium hypochlorite, solution … % Cl active |
| French français | hypochlorite de sodium, solution à … % de chlore actif |
| Croatian hrvatski | natrijev hipoklorit, otopina … % aktivnog Cl |
| Italian italiano | ipoclorito di sodio, soluzione … % Cl attivo |
| Latvian latviešu | nātrija hipohlorīts, šķīdums … % aktīvais Cl |
| Lithuanian lietuvių | … % Cl aktyv. natrio hipochlorito tirpalas |
| Hungarian magyar | nátrium-hipoklorit, oldat… % aktív klór |
| Maltese Malti | ipoklorit tas-sodju, soluzzjoni … % Cl attive |
| Dutch Nederlands | natriumhypochloriet, oplossing … % actief Cl |
| Polish polski | chloran(I) sodu, roztwór zawierający … % aktywnego Cl |
| Portuguese português | hipoclorito de sódio, solução a … % de Cl ativo |
| Romanian română | hipoclorit de sodiu, soluție de … % Cl activ |
| Slovak slovenčina | chlórnan sodný, roztok s … % aktívneho chlóru |
| Slovenian slovenščina | natrijev hipoklorit, raztopina … % aktivnega klora |
| Finnish suomi | natriumhypokloriitti, liuos, aktiivikloorin määrä … % |
| Swedish svenska | natriumhypoklorit, lösning … % aktivt klor |
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
Sodium hypochlorite GHS label elements
Everything CLP Annex VI fixes for Sodium hypochlorite, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Sodium hypochlorite
- Causes severe skin burns and eye damage.
- Causes serious eye damage.
- Very toxic to aquatic life.
- Very toxic to aquatic life with long lasting effects.
- Contact with acids liberates toxic gas.
- Do not breathe dust/fume/gas/mist/vapours/spray.
- Avoid release to the environment.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF IN EYES:
- Immediately call a POISON CENTER/doctor/…
- Do NOT induce vomiting.
- Remove contact lenses, if present and easy to do. Continue rinsing.
- Collect spillage.
- Dispose of contents/container to …
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Sodium hypochlorite in the GHS label constructor →
07 · Health hazards
Sodium hypochlorite health hazards and exposure limits
Sodium hypochlorite hazard summary
Corrosive to skin; [Quick CPC] Addition of acid to hypochlorite solution releases chlorine gas; Addition of ammonia releases chloramine gas; High inhalation exposure, especially if in confined space, can cause pulmonary edema; Ingestion can cause methemoglobinemia; Ingestion or 3% to 5% solution will cause burning of mouth and throat without other injury expected; [HSDB] Household bleaches (approximately 5% sodium hypochlorite) are irritants; more concentrated bleaches (10-15% sodium hypochlorite) are corrosive. [ICSC] The pentahydrate is decomposed by carbon dioxide in the air; The anhydrous form is highly explosive; [Merck Index] Only commercially produced as an aqueous solution; [EFSA] See Hypochlorous acid.
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Sodium hypochlorite carcinogenicity classification
Evaluation: There is inadequate evidence for the carcinogenicity of hypochlorite salts in experimental animals. No data were available from studies in humans on the carcinogenicity of hypochlorite salts. Overall evaluation: Hypochlorite salts are not classifiable as to their carcinogenicity to humans (Group 3). /Hypochlorite salts/
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.
08 · Physical and chemical properties
Sodium hypochlorite 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.
Sodium hypochlorite boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 111 °C (231.8 °F) | HSDB |
Sodium hypochlorite melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 18 °C (64.4 °F) | Pentahydrate | HSDB |
| -5 °C (23 °F) | ICSC | ||
| 18 °C (64.4 °F) | DOE PAC |
Sodium hypochlorite density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.025 g/cm³ | Sodium hypochlorite soln, diluted | HSDB |
| 1.093 g/cm³ | CAMEO | ||
| 1.0599 g/cm³ | at 21.11 °C | HSDB |
Sodium hypochlorite solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Solubility in water, g/l at 20 °C: 293 (good) | at 20 °C | ICSC |
| 29.3 g/100 g (0 °C) in water | at 0 °C | HSDB |
Sodium hypochlorite vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 15.0012 mmHg | at 20 °C | ICSC |
Sodium hypochlorite lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | Anhydrous sodium hypochlorite is very explosive. | HSDB |
Sodium hypochlorite odor threshold
| Property | Value | Conditions | Source |
|---|---|---|---|
| Odor threshold | The estimated odor threshold is the same as chlorine, 0.3 ppm | Haz-Map |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Sodium hypochlorite 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.
Sodium hypochlorite fire potential
FIRE RISK IN CONTACT WITH ORG MATERIALS.
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
Sodium hypochlorite storage and handling
Sodium hypochlorite reactive group
CAMEO Chemicals places Sodium hypochlorite in the reactive groups Oxidizing Agents, Strong, Salts, Basic, 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.
Sodium hypochlorite safe storage
Separated from acids. See Chemical Dangers. Cool. Keep in the dark. Well closed. Store only in original container.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Sodium hypochlorite storage conditions
Store at a temp not exceeding 20 °C away from acids in well-fitted air-tight bottles, closed with a glass stopper or suitable plastic cap. Protect from light. /Strong sodium hypochlorite soln/
Source: Hazardous Substances Data Bank (HSDB)
Sodium hypochlorite incompatible materials
Chlorination of ethyleneimine with sodium hypochlorite gives the explosive compound 1-chloroethyleneimine.
Source: Hazardous Substances Data Bank (HSDB)
Sodium hypochlorite reactivity
Salts of hypochlorous acid, HClO. Generally toxic, irritants and powerful oxidizers, particularly in the presence of water or at higher temperature as they decompose to release oxygen and chlorine gases. On contact with urea they form the highly explosive NCl3. When heated or on contact with acids, they produce highly toxic fumes of chlorine gas [Sax, 9th ed., 1996, p. 1905]. Can react with sulfuric acid to produce heat and chlorine gas.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Sodium hypochlorite in the storage compatibility matrix →
11 · Questions
Sodium hypochlorite — frequently asked questions
What is the CAS number of Sodium hypochlorite?
The CAS number of Sodium hypochlorite is 7681-52-9. Its EC number is 231-668-3.
What is the chemical formula of Sodium hypochlorite?
The molecular formula of Sodium hypochlorite is ClNaO and its molecular weight is 74.44 g/mol.
What does a Sodium hypochlorite label have to show?
Under CLP Annex VI the label for Sodium hypochlorite carries the pictograms Corrosion and Environment and the signal word is Danger.
Is Sodium hypochlorite flammable?
CLP Annex VI assigns Sodium hypochlorite 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 Sodium hypochlorite a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Sodium hypochlorite. 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 boiling point of Sodium hypochlorite?
The boiling point reported for Sodium hypochlorite is 111 °C (231.8 °F) (HSDB).
What is the melting point of Sodium hypochlorite?
The melting point reported for Sodium hypochlorite is 18 °C (64.4 °F), Pentahydrate (HSDB).
How should Sodium hypochlorite be stored?
Store at a temp not exceeding 20 °C away from acids in well-fitted air-tight bottles, closed with a glass stopper or suitable plastic cap. Protect from light. /Strong sodium hypochlorite soln/ (Hazardous Substances Data Bank (HSDB))
Nearby
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