Identification
| CAS number | 7681-52-9 |
|---|---|
| EC number | 231-668-3 |
| Physical form | liquid |
| Signal word | DANGER |
| Pictograms | GHS05 Corrosive; GHS09 Hazardous to the environment |
| Routes of exposure | skin, eyes, inhalation, ingestion |
Hazard classification
Harmonised classification from the GB mandatory classification list (index 017-011-00-1), with supplier self-classifications marked. The harmonised entry covers sodium hypochlorite solution and depends on available chlorine. EUH031 applies at 5% or more. Many suppliers add H290 (corrosive to metals).
- Skin corrosion, category 1B
- Serious eye damage, category 1
- Corrosive to metals, category 1 (supplier classification)
- Hazardous to the aquatic environment, acute category 1
- Hazardous to the aquatic environment, chronic category 1
Hazard statements
- H290 May be corrosive to metals. (supplier classification)
- 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.
- EUH031 Contact with acids liberates toxic gas.
Workplace exposure limit
No workplace exposure limit is listed in EH40/2005. Exposure must still be reduced as low as is reasonably practicable and adequately controlled.
Products that contain it
Common products whose hazard data comes from this record. The concentration and form vary, so always check the product data sheet.
- Domestos Original Thick Bleach (Domestos (Unilever)). Around 5% sodium hypochlorite. Corrosive; releases chlorine if mixed with acids.
- Parozone Thick Bleach (Parozone (Jeyes)). Thick bleach, similar strength to other household bleaches.
- Own brand thick bleach (Supermarket own brand). Tesco, Sainsbury's, Asda and similar. Check the label for the concentration.
- Milton Sterilising Fluid (Milton). Dilute hypochlorite (about 2%). Lower hazard than thick bleach but still keep away from acids.
- Chlorine granules (NaDCC) (Various (Haz-Tabs, Presept and similar)). Sodium dichloroisocyanurate tablets or granules release chlorine in water. Hazards close to hypochlorite; the solid is also an oxidiser. Check the product data sheet.
Common uses
- Surface disinfection
- Toilet and drain cleaning
- Laundry
First aid
Skin: remove contaminated clothing and rinse with plenty of water. Eyes: rinse for at least 15 minutes and get medical attention. Swallowed: rinse mouth, do not induce vomiting, call NHS 111.
In an emergency call 999. For advice call NHS 111. Always follow section 4 of the safety data sheet for the product you have.
Storage
Cool, dark, ventilated, closed container, away from acids and ammonia. Degrades in heat and light.
Sources
- HSE GB mandatory classification and labelling list (GB MCL), Index 017-011-00-1. Checked 8 September 2026.
- ECHA C&L Inventory, CAS 7681-52-9, ECHA 100.028.790. Checked 8 September 2026.
- HSE EH40/2005 Workplace exposure limits (2020 edition), Table 1. Checked 8 September 2026.
We do not host or copy manufacturer safety data sheets. Ask your supplier for the current sheet for the product you use.