Substances

Hydrogen peroxide

Also called peroxide, hair developer, cream peroxide.

An oxidiser and, at high concentration, a corrosive. The classification above is for concentrated solutions; hair developer at 3 to 12 per cent carries a lower classification. Check the data sheet for your product.

Last reviewed 8 September 2026

Hazard data from the HSE GB MCL, the ECHA C&L Inventory and HSE EH40, checked 8 September 2026. Classification checked automatically against the HSE GB mandatory classification list (version 8) and the ECHA C&L inventory on 9 September 2026. Confirm the concentration and form against the supplier data sheet for the product you use.

Identification

CAS number7722-84-1
EC number231-765-0
Physical formliquid
Signal wordDANGER
PictogramsGHS03 Oxidising; GHS05 Corrosive; GHS07 Harmful or irritant
Routes of exposureskin, eyes, inhalation, ingestion

Hazard classification

Harmonised classification from the GB mandatory classification list (index 008-003-00-9). The classification shown is for solutions of 70% and above. 50 to 70%: oxidising liquid category 2 and Skin Corr 1B. 35 to 50%: skin irritant, serious eye damage and respiratory irritant. 8 to 35%: serious eye damage only. 5 to 8%: eye irritant only. Hair developer at 3 to 12% therefore carries H318 or H319, not H314.

  • Oxidising liquid, category 1
  • Acute toxicity, category 4
  • Skin corrosion, category 1A

Hazard statements

  • H271 May cause fire or explosion; strong oxidiser.
  • H302 Harmful if swallowed.
  • H332 Harmful if inhaled.
  • H314 Causes severe skin burns and eye damage.

Workplace exposure limit

Reference periodppmmg/m³
Long term (8 hour TWA)11.4
Short term (15 minute)22.8

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.

  • Wella Welloxon Perfect developer (Wella). Cream peroxide at 1.9% to 12% (6 to 40 vol). Higher strengths damage eyes; wear gloves and eye protection when mixing.
  • Schwarzkopf Igora Royal Oil Developer (Schwarzkopf). Cream peroxide, 3% to 12%.
  • L'Oréal Oxydant Crème (L'Oréal Professionnel). Cream peroxide, 3% to 12%.
  • Hydrogen peroxide 3% solution (Various). Dilute solution. Much lower hazard than the concentrate the substance record describes; check the label.

Common uses

  • Hair colour developer
  • Disinfection
  • Bleaching

First aid

Skin and eyes: rinse with plenty of water. Eyes: get medical attention. Swallowed: rinse mouth and 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, ventilated, original vented container, away from combustible materials and metals.

Sources

We do not host or copy manufacturer safety data sheets. Ask your supplier for the current sheet for the product you use.