Sodium Hypochlorite

1Identification

Name

Sodium Hypochlorite

IUPAC name

sodium hypochlorite

CAS number

7681-52-9

EC number

231-668-3

Molecular formula

ClNaO

Molecular weight

74.44 g/mol

InChIKey

SUKJFIGYRHOWBL-UHFFFAOYSA-N

SMILES

[O-]Cl.[Na+]

PubChem CID

23665760

Synonyms

SODIUM HYPOCHLORITE, Antiformin, Clorox, Sodium oxychloride, Hypochlorous acid, sodium salt, Household bleach, Chlorox, Javex, Javelle water, Hypochlorite sodium, Youxiaolin, Chloros, Cloralex, Cloropool

Recommended uses

• Used as a disinfectant and bleaching agent with applications in the chemical, paper, textile, water treatment, and dairy industries; it is used to disinfectant water in swimming pools and cooling towers of power plants. [HSDB] 5% solution used as a hypo eliminator in photo development; [www.ci.tucson.az.us/arthazards/medium.html] Used in the EU on mushroom crops; Also used in the paint, lime, glass, pharmaceutical, metal (detoxify cyanide baths), and synthetics industries; [EFSA]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Electroplating [Category: Plate] Petroleum Production and Refining [Category: Industry] Pulp and Paper Processing [Category: Industry] Textiles (Fiber & Fabric Manufacturing) [Category: Industry] Using Disinfectants or Biocides [Category: Clean] Sewer and Wastewater Treatment [Category: Industry] Photographic Processing [Category: Other] Textiles (Printing, Dyeing, or Finishing) [Category: Industry] Farming (Respiratory Hazards) [Category: Industry] Glass Manufacturing [Category: Industry] Metal Extraction and Refining [Category: Industry]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Textile arts [Category: Hobbies]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• pH regulating agent Bleaching agent Other Anti-scaling agent Intermediate Processing aids, specific to petroleum production Oxidizing agent Cleaning agent Brightener Soil amendments (fertilizers) Not Known or Reasonably Ascertainable Sealant (barrier)
  EPA Chemical Data Reporting (CDR)
• Other Bleaching agent pH regulating agent Not Known or Reasonably Ascertainable Soil amendments (fertilizers) Sealant (barrier) Brightener Cleaning agent Oxidizing agent
  EPA Chemical Data Reporting (CDR)

Description

• Sodium hypochlorite appears as colorless or slightly yellow watery liquid with an odor of household bleach. Mixes with water. (USCG, 1999)
  CAMEO Chemicals
• Sodium hypochlorite is an inorganic sodium salt in which hypochlorite is the counterion. It is used as a bleaching and disinfecting agent and is commonly found in household bleach. It has a role as a bleaching agent and a disinfectant. It contains a hypochlorite.
  ChEBI
• Sodium Hypochlorite is a chlorine compound often used as a disinfectant or a bleaching agent. Sodium hypochlorite in 0.5% w/v solution is called Dakin's solution, and is used as an antiseptic to clean infected topical wounds.
  NCI Thesaurus (NCIt)

2Hazard identification

Signal word

Danger

Pictograms

GHS05, GHS09

Classification source

Regulation (EC) No 1272/2008 of the European Parliament and of the Council

Precautionary statements

Other reported classifications

6 classification records exist across sources. Differences usually reflect purity, physical form or impurities.

Health hazards

• INHALATION: Will produce severe bronchial irritation and pulmonary edema. INGESTION: burning of mouth, nausea and vomiting, delirium, coma. EYES & SKIN: can be irritating if contact is maintained. (USCG, 1999)
  CAMEO Chemicals
• · TOXIC and/or CORROSIVE; inhalation, ingestion or skin contact with material may cause severe injury or death. · Contact with molten substance may cause severe burns to skin and eyes. · Avoid any skin contact. · Fire may produce irritating, corrosive and/or toxic gases. · Runoff from fire control or dilution water may be corrosive and/or toxic and cause environmental contamination.
  Emergency Response Guidebook (ERG)

Fire hazards

• Special Hazards of Combustion Products: Store in a cool, dark place, away from combustible materials. Emits chlorine gas when burned. Behavior in Fire: May decompose, generating irritating chlorine gas. (USCG, 1999)
  CAMEO Chemicals
• · Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. · Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). · Corrosives in contact with metals may evolve flammable hydrogen gas. · Containers may explode when heated. · For electric vehicles or equipment, GUIDE 147 (lithium ion or sodium ion batteries) or GUIDE 138 (sodium batteries) should also be consulted.
  Emergency Response Guidebook (ERG)
• Not combustible. Gives off irritating or toxic fumes (or gases) in a fire. Heating will cause rise in pressure with risk of bursting.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Hazards 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;
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

3Composition / information on ingredients

This page describes the pure substance. Commercial products may be solutions or mixtures. Check Section 3 of your supplier's SDS for concentrations and other ingredients.

4First-aid measures

• INHALATION: Sips of milk or other demulcent. EYES: Flush with plenty of water for 15 minutes. SKIN: Wash contaminated area with soap and water. (USCG, 1999)
  CAMEO Chemicals
• General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).
  Emergency Response Guidebook (ERG)

Symptoms of exposure

• Cough. Sore throat.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness. Pain.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Burning sensation. Sore throat. Cough. Abdominal pain. Vomiting. Diarrhoea.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• If material involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. /Hypochlorite soln (containing more than 7% available chlorine, by wt)/
  Hazardous Substances Data Bank (HSDB)
• Cool exposed containers with water. /Monohydrate/
  Hazardous Substances Data Bank (HSDB)

Hazardous combustion products

• RELEASES CHLORINE WHEN HEATED ABOVE 35 °C
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Isolation and evacuation

• Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary. FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
  CAMEO Chemicals
• Immediate precautionary measure · Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. Spill · For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances. · For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary. Fire · If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.
  Emergency Response Guidebook (ERG)

Spill cleanup

• Personal protection: filter respirator for inorganic gases and vapours adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Ventilation. Collect leaking and spilled liquid in covered non-metallic containers as far as possible. Wash away remainder with plenty of water.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Environmental considerations-land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete; absorb bulk liquid with fly ash or cement powder; neutralize with agricultural lime (CaO), crushed limestone (CaCO3), or sodium bicarbonate (NaHCO3) /Sodium hypochlorite soln (Hypochlorite soln containing not more than 7% available chlorine, by wt)/
  Hazardous Substances Data Bank (HSDB)
• Environmental considerations- water spill: Neutralize with agricultural lime (CaO), crushed limestone (CaCO3), or sodium bicarbonate (NaHCO3); if dissolved, in region of 10 ppm or greater concn, apply activated carbon at 10 times the spilled amt; use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates. /Sodium hypochlorite soln (Hypochlorite soln containing not more than 7% available chlorine, by wt)/
  Hazardous Substances Data Bank (HSDB)
• Environmental considerations- air spill: Apply water spray or mist to knock down vapors. /Sodium hypochlorite soln (Hypochlorite soln containing not more than 7% available chlorine, by wt)/
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Separated from acids. See Chemical Dangers. Cool. Keep in the dark. Well closed. Store only in original container.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• 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)
• Vent caps should be checked with full personal protection, and material should be stored at 15-18 °C and out of direct sunlight. ...
  Hazardous Substances Data Bank (HSDB)
• Solutions in water are storage hazards due to oxygen evolution.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

No occupational exposure limits found in our sources.

Personal protective equipment

• Rubber gloves, goggles, self-contained breathing apparatus, plastic coveralls and boots. (USCG, 1999)
  CAMEO Chemicals
• Personnel protection: ... Wear appropriate chemical protective gloves, boots and goggles /Hypochlorite soln (containing not more than 7% available chlorine, by wt)/
  Hazardous Substances Data Bank (HSDB)

9Physical and chemical properties

10Stability and reactivity

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.
  CAMEO Chemicals
• Water soluble. Decomposes into chlorine and oxygen gases in hot water.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Chlorination of ethyleneimine with sodium hypochlorite gives the explosive compound 1-chloroethyleneimine.
  Hazardous Substances Data Bank (HSDB)
• Primary amines and calcium hypochlorite or sodium hypochlorite react to form normal chloroamines, which are explosive.
  Hazardous Substances Data Bank (HSDB)
• Hypochlorites react with urea to form nitrogen trichloride which explodes spontaneously in air. /Hypochlorites/
  Hazardous Substances Data Bank (HSDB)

Chemical stability

• UNSTABLE IN AIR UNLESS MIXED WITH SODIUM HYDROXIDE.
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Short-term exposure effects

• The substance is irritating to the eyes, skin, respiratory tract and digestive tract.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Long-term exposure effects

• Repeated or prolonged contact with skin may cause dermatitis.
  ILO-WHO International Chemical Safety Cards (ICSCs)

12Ecological information

Not available in the public sources we compile. Check Section 12 of the supplier's SDS.

13Disposal considerations

• SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
  Hazardous Substances Data Bank (HSDB)

14Transport information

UN number: UN 1791

Shipping name

• UN 1791; Hypochlorite solutions
  Hazardous Substances Data Bank (HSDB)
• IMO 8.0; Hypochlorite solutions
  Hazardous Substances Data Bank (HSDB)

DOT hazard class

• Sodium hypochlorite solution
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• Marine pollutant
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172

DOT label

• Corrosive
  CAMEO Chemicals

UN classification

• UN Hazard Class: 8
  ILO-WHO International Chemical Safety Cards (ICSCs)

Emergency Response Guidebook

• 1791 154
  Emergency Response Guidebook (ERG)

How DOT hazard classes work →

15Regulatory information

• As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996.
  Hazardous Substances Data Bank (HSDB)
• Designated as a hazardous substance under section 311(b)(2)(A) of the Federal Water Pollution Control Act and further regulated by the Clean Water Act Amendments of 1977 and 1978. These regulations apply to discharges of this substance.
  Hazardous Substances Data Bank (HSDB)
• Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 100 lb or 45.4 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).
  Hazardous Substances Data Bank (HSDB)
• Sodium hypochlorite is an indirect food additive for use only as a component of adhesives.
  Hazardous Substances Data Bank (HSDB)

Overview of SDS regulations (OSHA HazCom, WHMIS, REACH/CLP) →

16Other information

Compiled from PubChem CID 23665760 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.